Sample records for composite floor tubes

  1. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Keiser, J.R.; Taljat, B.; Wang, X.L.

    Cracking of co-extruded (generally identified as composite) floor tubes in kraft black liquor recovery boilers was first observed in Scandinavia, but this problem has now been found in many North American boilers. In most cases, cracking in the outer 304L stainless steel has not progressed into the carbon steel, but the potential for such crack propagation is a cause of concern. A multidimensional study has been initiated to characterize the cracking seen in composite floor tubes, to measure the residual stresses resulting from composite tube fabrication, and to predict the stresses in tubes under operating conditions. The characterization studies includemore » review of available reports and documents on composite tube cracking, metallographic examination of a substantial number of cracked tubes, and evaluation of the dislocation structure in cracked tubes. Neutron and X-ray diffraction are being used to determine the residual stresses in composite tubes from two major manufacturers, and finite element analysis is being used to predict the stresses in the tubes during normal operation and under conditions where thermal fluctuations occur.« less

  2. Materials for the pulp and paper industry. Section 1: Development of materials for black liquor recovery boilers

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Keiser, J.R.; Hubbard, C.R.; Payzant, E.A.

    1997-04-01

    Black liquor recovery boilers are essential components of kraft pulp and paper mills because they are a critical element of the system used to recover the pulping chemicals required in the kraft pulping process. In addition, the steam produced in these boilers is used to generate a significant portion of the electrical power used in the mill. Recovery boilers require the largest capital investment of any individual component of a paper mill, and these boilers are a major source of material problems in a mill. The walls and floors of these boilers are constructed of tube panels that circulate highmore » pressure water. Molten salts (smelt) accumulate on the floor of recovery boilers, and leakage of water into the boiler can result in a violent explosion when the leaked water instantly vaporizes upon contacting the molten smelt. Because corrosion of the conventionally-used carbon steel tubing was found to be excessive in the lower section of recovery boilers, use of stainless steel/carbon steel co-extruded tubing was adopted for boiler walls to lessen corrosion and reduce the likelihood of smelt/water explosions. Eventually, this co-extruded or composite (as it is known in the industry) tubing was selected for use as a portion or all of the floor of recovery boilers, particularly those operating at pressures > 6.2 MPa (900 psi), because of the corrosion problems encountered in carbon steel floor tubes. Since neither the cause of the cracking nor an effective solution has been identified, this program was established to develop a thorough understanding of the degradation that occurs in the composite tubing used for walls and floors. This is being accomplished through a program that includes collection and review of technical reports, examination of unexposed and cracked tubes from boiler floors, computer modeling to predict residual stresses under operating conditions, and operation of laboratory tests to study corrosion, stress corrosion cracking, and thermal fatigue.« less

  3. Production and crosslinking of multi-layer tubes (PE & metal) by E-beam

    NASA Astrophysics Data System (ADS)

    Zyball, Alfred

    2000-03-01

    Irradiation crosslinking of PE-tubes has been used for heating floors for about 25 years. Such tubes are also used today for drinking water supply. A further development has been the coating of such tubes with Ethylene-Vinyl-Alcohol-Copolymers (EVAL), in order to prevent oxygen diffusion into the water through the PE tube. For about 15 years composite tubes made of PE and aluminum have been available. These tubes are crosslinked with electron beams. The energy of the accelerated electrons must be adjusted for the particular tube configuration, so that the inner PE-layer will be crosslinked. This paper will concern itself with the manufacture and the crosslinking of composite tubes.

  4. Modification of one man life raft

    NASA Technical Reports Server (NTRS)

    Soter, E. J. (Inventor)

    1974-01-01

    A one man inflatable life raft is described. The raft has an inflatable tube perimetrically bounding the occupant receiving space with a flexible floor member. A zippered opening in the floor allows entry and facilitates the use of a constant diameter tube. An airtight fabric bulkhead divides the peripheral tube longitudinally into inflatable tube sections, where if either tube section were punctured, the bulkhead would move into the punctured section to substitute for the punctured wall portion and maintain the inflatable volume of the tube. The floor member is attached to the central portion of the tube wall so that either side of the raft can be the up side.

  5. 27 CFR 46.231 - Floor stocks tax return.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette....28T09, 2009 Floor Stocks Tax Return—Tobacco Products and Cigarette Papers and Tubes, is available for...

  6. 27 CFR 46.231 - Floor stocks tax return.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette....28T09, 2009 Floor Stocks Tax Return—Tobacco Products and Cigarette Papers and Tubes, is available for...

  7. 27 CFR 46.231 - Floor stocks tax return.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette....28T09, 2009 Floor Stocks Tax Return—Tobacco Products and Cigarette Papers and Tubes, is available for...

  8. 27 CFR 46.231 - Floor stocks tax return.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette....28T09, 2009 Floor Stocks Tax Return—Tobacco Products and Cigarette Papers and Tubes, is available for...

  9. 27 CFR 46.231 - Floor stocks tax return.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette....28T09, 2009 Floor Stocks Tax Return—Tobacco Products and Cigarette Papers and Tubes, is available for...

  10. Design, Fabrication, and Testing of a Composite Rack Prototype in Support of the Deep Space Habitat Program

    NASA Technical Reports Server (NTRS)

    Smith, Russ; Hagen, Richard

    2015-01-01

    In support of the Deep Space Habitat project a number of composite rack prototypes were developed, designed, fabricated and tested to various extents ( with the International Standard Payload Rack configuration, or crew quarters, as a baseline). This paper focuses specifically on a composite rack prototype with a direct tie in to Space Station hardware. The outlined prototype is an all composite construction, excluding metallic fasteners, washers, and their associated inserts. The rack utilizes braided carbon composite tubing for the frame with the sidewalls, backwall and flooring sections utilizing aircraft grade composite honeycomb sandwich panels. Novel additively manufactured thermoplastic joints and tube inserts were also developed in support of this effort. Joint and tube insert screening tests were conducted at a preliminary level. The screening tests allowed for modification, and enhancement, of the fabrication and design approaches, which will be outlined. The initial joint tests did not include mechanical fasteners. Adhesives were utilized at the joint to composite tube interfaces, along with mechanical fasteners during final fabrication (thus creating a stronger joint than the adhesive only variant). In general the prototype was focused on a potential in-space assembly approach, or kit-of-parts construction concept, which would not necessarily require the inclusion of an adhesive in the joint regions. However, given the tie in to legacy Station hardware (and potential flight loads with imbedded hardware mass loadings), the rack was built as stiff and strong as possible. Preliminary torque down tests were also conducted to determine the feasibility of mounting the composite honeycomb panels to the composite tubing sections via the additively manufactured tube inserts. Additional fastener torque down tests were also conducted with inserts (helicoils) imbedded within the joints. Lessons learned are also included and discussed.

  11. 27 CFR 46.193 - Persons liable for floor stocks tax.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 General § 46.193 Persons liable for floor...

  12. 27 CFR 46.233 - Payment of floor stocks tax.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Filing Requirements § 46.233 Payment of floor stocks tax. (a...

  13. 27 CFR 46.233 - Payment of floor stocks tax.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Filing Requirements § 46.233 Payment of floor stocks tax. (a...

  14. 27 CFR 46.193 - Persons liable for floor stocks tax.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 General § 46.193 Persons liable for floor...

  15. 27 CFR 46.193 - Persons liable for floor stocks tax.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 General § 46.193 Persons liable for floor...

  16. 27 CFR 46.233 - Payment of floor stocks tax.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Filing Requirements § 46.233 Payment of floor stocks tax. (a...

  17. 27 CFR 46.193 - Persons liable for floor stocks tax.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 General § 46.193 Persons liable for floor...

  18. 27 CFR 46.193 - Persons liable for floor stocks tax.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 General § 46.193 Persons liable for floor...

  19. 27 CFR 46.233 - Payment of floor stocks tax.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Filing Requirements § 46.233 Payment of floor stocks tax. (a...

  20. 27 CFR 46.194 - Persons not liable for floor stocks tax.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 General § 46.194 Persons not liable for floor...

  1. 27 CFR 46.194 - Persons not liable for floor stocks tax.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 General § 46.194 Persons not liable for floor...

  2. 27 CFR 46.194 - Persons not liable for floor stocks tax.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 General § 46.194 Persons not liable for floor...

  3. 27 CFR 46.194 - Persons not liable for floor stocks tax.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 General § 46.194 Persons not liable for floor...

  4. 27 CFR 46.194 - Persons not liable for floor stocks tax.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 General § 46.194 Persons not liable for floor...

  5. A temperature-sensitive mutation in the nodal-related gene cyclops reveals that the floor plate is induced during gastrulation in zebrafish.

    PubMed

    Tian, Jing; Yam, Caleb; Balasundaram, Gayathri; Wang, Hui; Gore, Aniket; Sampath, Karuna

    2003-07-01

    The floor plate, a specialized group of cells in the ventral midline of the neural tube of vertebrates, plays crucial roles in patterning the central nervous system. Recent work from zebrafish, chick, chick-quail chimeras and mice to investigate the development of the floor plate have led to several models of floor-plate induction. One model suggests that the floor plate is formed by inductive signalling from the notochord to the overlying neural tube. The induction is thought to be mediated by notochord-derived Sonic hedgehog (Shh), a secreted protein, and requires direct cellular contact between the notochord and the neural tube. Another model proposes a role for the organizer in generating midline precursor cells that produce floor plate cells independent of notochord specification, and proposes that floor plate specification occurs early, during gastrulation. We describe a temperature-sensitive mutation that affects the zebrafish Nodal-related secreted signalling factor, Cyclops, and use it to address the issue of when the floor plate is induced in zebrafish. Zebrafish cyclops regulates the expression of shh in the ventral neural tube. Although null mutations in cyclops result in the lack of the medial floor plate, embryos homozygous for the temperature-sensitive mutation have floor plate cells at the permissive temperature and lack floor plate cells at the restrictive temperature. We use this mutant allele in temperature shift-up and shift-down experiments to answer a central question pertaining to the timing of vertebrate floor plate induction. Abrogation of Cyc/Nodal signalling in the temperature-sensitive mutant embryos at various stages indicates that the floor plate in zebrafish is induced early in development, during gastrulation. In addition, continuous Cyclops signalling is required through gastrulation for a complete ventral neural tube throughout the length of the neuraxis. Finally, by modulation of Nodal signalling levels in mutants and in ectopic overexpression experiments, we show that, similar to the requirements for prechordal plate mesendoderm fates, uninterrupted and high levels of Cyclops signalling are required for induction and specification of a complete ventral neural tube.

  6. 27 CFR 46.191 - Purpose of this subpart.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette... subpart implement the floor stocks tax on certain tobacco products, cigarette papers, and cigarette tubes...

  7. 27 CFR 46.191 - Purpose of this subpart.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette... subpart implement the floor stocks tax on certain tobacco products, cigarette papers, and cigarette tubes...

  8. 27 CFR 46.191 - Purpose of this subpart.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette... subpart implement the floor stocks tax on certain tobacco products, cigarette papers, and cigarette tubes...

  9. 27 CFR 46.191 - Purpose of this subpart.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette... subpart implement the floor stocks tax on certain tobacco products, cigarette papers, and cigarette tubes...

  10. 27 CFR 46.191 - Purpose of this subpart.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette... subpart implement the floor stocks tax on certain tobacco products, cigarette papers, and cigarette tubes...

  11. 27 CFR 46.232 - Preparation of floor stocks tax return.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Filing Requirements § 46.232 Preparation of...

  12. 27 CFR 46.232 - Preparation of floor stocks tax return.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Filing Requirements § 46.232 Preparation of...

  13. 27 CFR 46.232 - Preparation of floor stocks tax return.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Filing Requirements § 46.232 Preparation of...

  14. 27 CFR 46.232 - Preparation of floor stocks tax return.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Filing Requirements § 46.232 Preparation of...

  15. 27 CFR 46.232 - Preparation of floor stocks tax return.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Filing Requirements § 46.232 Preparation of...

  16. Sound absorption characteristics of tree bark and forest floor

    Treesearch

    G. Reethof; O. H. McDaniel; G. M. Heisler

    1977-01-01

    Results of basic research on absorption of sound by tree bark and forest floors are presented. Amount of sound absorption by tree bark was determined by laboratory experiments with bark samples in a standing-wave tube. A modified portable standing-wave tube was used to measure absorption of sound by forest floors with different moisture contents, with and without leaf...

  17. VIEW FROM DRAFT TUBE LOOKING UP TOWARDS THE GENERATOR FLOOR, ...

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

    VIEW FROM DRAFT TUBE LOOKING UP TOWARDS THE GENERATOR FLOOR, DRAFT CONE IN FOREGROUND. - Wilson Dam & Hydroelectric Plant, Turbine & Generator Unit, Spanning Tennessee River at Wilson Dam Road (Route 133), Muscle Shoals, Colbert County, AL

  18. Discussion on the installation checking method of precast composite floor slab with lattice girders

    NASA Astrophysics Data System (ADS)

    Chen, Li; Jin, Xing; Wang, Yahui; Zhou, Hele; Gu, Jianing

    2018-03-01

    Based on the installation checking requirements of China’s current standards and the international norms for prefabricated structural precast components, it proposed an installation checking method for precast composite floor slab with lattice girders. By taking an equivalent composite beam consisted of a single lattice girder and the precast concrete slab as the checking object, compression instability stress of upper chords and yield stress of slab distribution reinforcement at the maximum positive moment, tensile yield stress of upper chords, slab normal section normal compression stress and shear instability stress of diagonal bars at the maximum negative moment were checked. And the bending stress and deflection of support beams, strength and compression stability bearing capacity of the vertical support, shear bearing capacity of the bolt and compression bearing capacity of steel tube wall at the bolt were checked at the same time. Every different checking object was given a specific load value and load combination. Application of installation checking method was given and testified by example.

  19. Spring tube braces for seismic isolation of buildings

    NASA Astrophysics Data System (ADS)

    Karayel, V.; Yuksel, Ercan; Gokce, T.; Sahin, F.

    2017-01-01

    A new low-cost seismic isolation system based on spring tube bracings has been proposed and studied at the Structural and Earthquake Engineering Laboratory of Istanbul Technical University. Multiple compression-type springs are positioned in a special cylindrical tube to obtain a symmetrical response in tension and compression-type axial loading. An isolation floor, which consists of pin-ended steel columns and spring tube bracings, is constructed at the foundation level or any intermediate level of the building. An experimental campaign with three stages was completed to evaluate the capability of the system. First, the behavior of the spring tubes subjected to axial displacement reversals with varying frequencies was determined. In the second phase, the isolation floor was assessed in the quasi-static tests. Finally, a ¼ scaled 3D steel frame was tested on the shake table using actual acceleration records. The transmitted acceleration to the floor levels is greatly diminished because of the isolation story, which effects longer period and higher damping. There are no stability and self-centering problems in the isolation floor.

  20. VIEW OF MISSILE TUBE AT THE GROUND FLOOR LEVEL. VIEW ...

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

    VIEW OF MISSILE TUBE AT THE GROUND FLOOR LEVEL. VIEW FACING SOUTH - U.S. Naval Base, Pearl Harbor, Ford Island Polaris Missile Lab & U.S. Fleet Ballistic Missile Submarine Training Center, Between Lexington Boulvevard and the sea plane ramps on the southwest side of Ford Island, Pearl City, Honolulu County, HI

  1. VIEW OF MISSILE TUBE AT THE GROUND FLOOR LEVEL. VIEW ...

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

    VIEW OF MISSILE TUBE AT THE GROUND FLOOR LEVEL. VIEW FACING EAST - U.S. Naval Base, Pearl Harbor, Ford Island Polaris Missile Lab & U.S. Fleet Ballistic Missile Submarine Training Center, Between Lexington Boulvevard and the sea plane ramps on the southwest side of Ford Island, Pearl City, Honolulu County, HI

  2. DETAIL OF INTERIOR OF MISSILE TUBE AT GROUND FLOOR LEVEL ...

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

    DETAIL OF INTERIOR OF MISSILE TUBE AT GROUND FLOOR LEVEL SHOWING AIR COMPRESSOR TANKS AND CURVING STEEL PIECE. VIEW FACING EAST - U.S. Naval Base, Pearl Harbor, Ford Island Polaris Missile Lab & U.S. Fleet Ballistic Missile Submarine Training Center, Between Lexington Boulvevard and the sea plane ramps on the southwest side of Ford Island, Pearl City, Honolulu County, HI

  3. Properties of lightweight cement-based composites containing waste polypropylene

    NASA Astrophysics Data System (ADS)

    Záleská, Martina; Pavlíková, Milena; Pavlík, Zbyšek

    2016-07-01

    Improvement of buildings thermal stability represents an increasingly important trend of the construction industry. This work aims to study the possible use of two types of waste polypropylene (PP) for the development of lightweight cement-based composites with enhanced thermal insulation function. Crushed PP waste originating from the PP tubes production is used for the partial replacement of silica sand by 10, 20, 30, 40 and 50 mass%, whereas a reference mixture without plastic waste is studied as well. First, basic physical and thermal properties of granular PP random copolymer (PPR) and glass fiber reinforced PP (PPGF) aggregate are studied. For the developed composite mixtures, basic physical, mechanical, heat transport and storage properties are accessed. The obtained results show that the composites with incorporated PP aggregate exhibit an improved thermal insulation properties and acceptable mechanical resistivity. This new composite materials with enhanced thermal insulation function are found to be promising materials for buildings subsoil or floor structures.

  4. 27 CFR 46.262 - Application.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... THE TREASURY (CONTINUED) TOBACCO MISCELLANEOUS REGULATIONS RELATING TO TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held...

  5. 27 CFR 46.270 - [Reserved

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... THE TREASURY (CONTINUED) TOBACCO MISCELLANEOUS REGULATIONS RELATING TO TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held...

  6. 27 CFR 46.270 - [Reserved

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... THE TREASURY (CONTINUED) TOBACCO MISCELLANEOUS REGULATIONS RELATING TO TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held...

  7. 27 CFR 46.270 - [Reserved

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... THE TREASURY (CONTINUED) TOBACCO MISCELLANEOUS REGULATIONS RELATING TO TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held...

  8. 27 CFR 46.270 - [Reserved

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... THE TREASURY (CONTINUED) TOBACCO MISCELLANEOUS REGULATIONS RELATING TO TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held...

  9. 27 CFR 46.270 - [Reserved

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... THE TREASURY (CONTINUED) TOBACCO MISCELLANEOUS REGULATIONS RELATING TO TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held...

  10. 27 CFR 46.223 - Tax credit.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... THE TREASURY (CONTINUED) TOBACCO MISCELLANEOUS REGULATIONS RELATING TO TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held...

  11. 27 CFR 46.223 - Tax credit.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... THE TREASURY (CONTINUED) TOBACCO MISCELLANEOUS REGULATIONS RELATING TO TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held...

  12. 27 CFR 46.223 - Tax credit.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... THE TREASURY (CONTINUED) TOBACCO MISCELLANEOUS REGULATIONS RELATING TO TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held...

  13. 27 CFR 46.223 - Tax credit.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... THE TREASURY (CONTINUED) TOBACCO MISCELLANEOUS REGULATIONS RELATING TO TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held...

  14. 27 CFR 46.223 - Tax credit.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... THE TREASURY (CONTINUED) TOBACCO MISCELLANEOUS REGULATIONS RELATING TO TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held...

  15. 27 CFR 46.221 - Floor stocks tax rates.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette... Floor stocks tax rate Small cigars $48.502 per thousand. Small cigarettes 30.83 per thousand. Large cigarettes 6½ inch or less in length 64.74 per thousand. Large cigarettes more than 6½ inch in length 30.83...

  16. 27 CFR 46.221 - Floor stocks tax rates.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette... Floor stocks tax rate Small cigars $48.502 per thousand. Small cigarettes 30.83 per thousand. Large cigarettes 61/2 inch or less in length 64.74 per thousand. Large cigarettes more than 61/2 inch in length 30...

  17. 27 CFR 46.195 - Floor stocks requirements.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Tubes Held for Sale on April 1, 2009 General § 46.195 Floor stocks requirements. (a) Take inventory. The dealer must establish the quantity of articles subject to the floor stocks tax held for sale on April 1, 2009. The dealer may take a physical inventory or may use a record (book) inventory, as specified in...

  18. 27 CFR 46.221 - Floor stocks tax rates.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette... Floor stocks tax rate Small cigars $48.502 per thousand. Small cigarettes 30.83 per thousand. Large cigarettes 61/2 inch or less in length 64.74 per thousand. Large cigarettes more than 61/2 inch in length 30...

  19. 27 CFR 46.221 - Floor stocks tax rates.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette... Floor stocks tax rate Small cigars $48.502 per thousand. Small cigarettes 30.83 per thousand. Large cigarettes 6½ inch or less in length 64.74 per thousand. Large cigarettes more than 6½ inch in length 30.83...

  20. 27 CFR 46.221 - Floor stocks tax rates.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette... Floor stocks tax rate Small cigars $48.502 per thousand. Small cigarettes 30.83 per thousand. Large cigarettes 6½ inch or less in length 64.74 per thousand. Large cigarettes more than 6½ inch in length 30.83...

  1. BOILING HOUSE, INTERIOR, SECOND FLOOR, GARVER CLARIFIER IN FOREGROUND, TOPS ...

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

    BOILING HOUSE, INTERIOR, SECOND FLOOR, GARVER CLARIFIER IN FOREGROUND, TOPS OF LONG TUBE EVAPORATORS IN BACKGROUND. VIEW FROM NORTHWEST - Kekaha Sugar Company, Sugar Mill Building, 8315 Kekaha Road, Kekaha, Kauai County, HI

  2. Resolution of lava tubes with ground penetrating radar: preliminary results from the TubeX project

    NASA Astrophysics Data System (ADS)

    Esmaeili, S.; Kruse, S.; Garry, W. B.; Whelley, P.; Young, K.; Jazayeri, S.; Bell, E.; Paylor, R.

    2017-12-01

    As early as the mid 1970's it was postulated that planetary tubes or caves on other planetary bodies (i.e., the Moon or Mars) could provide safe havens for human crews, protect life and shield equipment from harmful radiation, rapidly fluctuating surface temperatures, and even meteorite impacts. What is not clear, however, are the exploration methods necessary to evaluate a potential tube-rich environment to locate suitable tubes suitable for human habitation. We seek to address this knowledge gap using a suite of instruments to detect and document tubes in a terrestrial analog study at Lava Beds National Monument, California, USA. Here we describe the results of ground penetrating radar (GPR) profiles and light detection and ranging (LiDAR) scans. Surveys were conducted from the surface and within four lava tubes (Hercules Leg, Skull, Valentine and, Indian Well Caves) with varying flow composition, shape, and complexity. Results are shown across segments of these tubes where the tubes are <1 m to ranging > 10 m in height and the ceilings are 1 - 10 m below the surface. The GPR profiles over the tubes are, as expected, complex, due to scattering from fractures in roof material and three-dimensional heterogeneities. Point clouds derived from the LiDAR scans of both the interior and exterior of the lava tubes provide precise positioning of the tube geometry and depth of the ceiling and floor with respect to the surface topography. GPR profiles over LiDAR-mapped tube cross-sections are presented and compared against synthetic models of radar response to the measured geometry. This comparison will help to better understand the origins of characteristic features in the radar profiles. We seek to identify the optimal data processing and migration approaches to aid lava tube exploration of planetary surfaces.

  3. 27 CFR 46.235 - Filing requirements for multiple locations.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Filing Requirements § 46.235 Filing...

  4. 27 CFR 46.235 - Filing requirements for multiple locations.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Filing Requirements § 46.235 Filing...

  5. 27 CFR 46.235 - Filing requirements for multiple locations.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Filing Requirements § 46.235 Filing...

  6. 27 CFR 46.235 - Filing requirements for multiple locations.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Filing Requirements § 46.235 Filing...

  7. 27 CFR 46.235 - Filing requirements for multiple locations.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Filing Requirements § 46.235 Filing...

  8. Improved, Low-Stress Economical Submerged Pipeline

    NASA Technical Reports Server (NTRS)

    Jones, Jack A.; Chao, Yi

    2011-01-01

    A preliminary study has shown that the use of a high-strength composite fiber cloth material may greatly reduce fabrication and deployment costs of a subsea offshore pipeline. The problem is to develop an inexpensive submerged pipeline that can safely and economically transport large quantities of fresh water, oil, and natural gas underwater for long distances. Above-water pipelines are often not feasible due to safety, cost, and environmental problems, and present, fixed-wall, submerged pipelines are often very expensive. The solution is to have a submerged, compliant-walled tube that when filled, is lighter than the surrounding medium. Some examples include compliant tubes for transporting fresh water under the ocean, for transporting crude oil underneath salt or fresh water, and for transporting high-pressure natural gas from offshore to onshore. In each case, the fluid transported is lighter than its surrounding fluid, and thus the flexible tube will tend to float. The tube should be ballasted to the ocean floor so as to limit the motion of the tube in the horizontal and vertical directions. The tube should be placed below 100-m depth to minimize biofouling and turbulence from surface storms. The tube may also have periodic pumps to maintain flow without over-pressurizing, or it can have a single pump at the beginning. The tube may have periodic valves that allow sections of the tube to be repaired or maintained. Some examples of tube materials that may be particularly suited for these applications are non-porous composite tubes made of high-performance fibers such as Kevlar, Spectra, PBO, Aramid, carbon fibers, or high-strength glass. Above-ground pipes for transporting water, oil, and natural gas have typically been fabricated from fiber-reinforced plastic or from more costly high-strength steel. Also, previous suggested subsea pipeline designs have only included heavy fixed-wall pipes that can be very expensive initially, and can be difficult and expensive to deploy for long distances. A much less expensive Kevlar pipeline can be coiled up on a ship s deck and deployed in the water as the ship moves. Support ships can be used to drop sand into conduits below the uninflated tube, so that the tube remains in place when more buoyant fresh water later fills the tubes.

  9. 27 CFR 46.242 - Period for maintaining records.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Records § 46.242 Period for maintaining records. The dealer...

  10. 27 CFR 46.242 - Period for maintaining records.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Records § 46.242 Period for maintaining records. The dealer...

  11. 27 CFR 46.273 - Refusing entry or examination.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Ttb Authorities § 46.273 Refusing entry or examination. If...

  12. 27 CFR 46.271 - Entry, examination and testimony.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Ttb Authorities § 46.271 Entry, examination and testimony...

  13. 27 CFR 46.273 - Refusing entry or examination.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Ttb Authorities § 46.273 Refusing entry or examination. If...

  14. 27 CFR 46.242 - Period for maintaining records.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Records § 46.242 Period for maintaining records. The dealer...

  15. 27 CFR 46.271 - Entry, examination and testimony.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Ttb Authorities § 46.271 Entry, examination and testimony...

  16. 27 CFR 46.203 - Record (book) inventory requirements.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Inventories § 46.203 Record (book) inventory requirements. (a...

  17. 27 CFR 46.203 - Record (book) inventory requirements.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Inventories § 46.203 Record (book) inventory requirements. (a...

  18. 27 CFR 46.273 - Refusing entry or examination.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Ttb Authorities § 46.273 Refusing entry or examination. If...

  19. 27 CFR 46.271 - Entry, examination and testimony.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Ttb Authorities § 46.271 Entry, examination and testimony...

  20. 27 CFR 46.203 - Record (book) inventory requirements.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Inventories § 46.203 Record (book) inventory requirements. (a...

  1. 27 CFR 46.242 - Period for maintaining records.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Records § 46.242 Period for maintaining records. The dealer...

  2. 27 CFR 46.271 - Entry, examination and testimony.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Ttb Authorities § 46.271 Entry, examination and testimony...

  3. 27 CFR 46.203 - Record (book) inventory requirements.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Inventories § 46.203 Record (book) inventory requirements. (a...

  4. 27 CFR 46.242 - Period for maintaining records.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Records § 46.242 Period for maintaining records. The dealer...

  5. 27 CFR 46.271 - Entry, examination and testimony.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Ttb Authorities § 46.271 Entry, examination and testimony...

  6. 27 CFR 46.203 - Record (book) inventory requirements.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Inventories § 46.203 Record (book) inventory requirements. (a...

  7. 27 CFR 46.273 - Refusing entry or examination.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Ttb Authorities § 46.273 Refusing entry or examination. If...

  8. 27 CFR 46.192 - Definitions used in this subpart.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 General § 46.192 Definitions used in this subpart. As used in..., Miscellaneous Regulations Relating to Tobacco Products and Cigarette Papers and Tubes. (b) Articles subject to...

  9. 27 CFR 46.192 - Definitions used in this subpart.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 General § 46.192 Definitions used in this subpart. As used in..., Miscellaneous Regulations Relating to Tobacco Products and Cigarette Papers and Tubes. (b) Articles subject to...

  10. 27 CFR 46.192 - Definitions used in this subpart.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 General § 46.192 Definitions used in this subpart. As used in..., Miscellaneous Regulations Relating to Tobacco Products and Cigarette Papers and Tubes. (b) Articles subject to...

  11. 27 CFR 46.192 - Definitions used in this subpart.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 General § 46.192 Definitions used in this subpart. As used in..., Miscellaneous Regulations Relating to Tobacco Products and Cigarette Papers and Tubes. (b) Articles subject to...

  12. 27 CFR 46.192 - Definitions used in this subpart.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 General § 46.192 Definitions used in this subpart. As used in..., Miscellaneous Regulations Relating to Tobacco Products and Cigarette Papers and Tubes. (b) Articles subject to...

  13. VIEW OF THE PRODUCTION FLOOR OF BUILDING 460. BUILDING 460 ...

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

    VIEW OF THE PRODUCTION FLOOR OF BUILDING 460. BUILDING 460 WAS CONSTRUCTED FOR THE MANUFACTURE OF STAINLESS STEEL COMPONENTS SUCH AS RESERVOIRS, TUBES, AND NON-FISSILE TRIGGER COMPONENTS. MANUFACTURING, TESTING, AND INSPECTION PROCESSES OCCUPIED MOST OF THE GROUND FLOOR. (2/20/96) - Rocky Flats Plant, Stainless Steel & Non-Nuclear Components Manufacturing, Southeast corner of intersection of Cottonwood & Third Avenues, Golden, Jefferson County, CO

  14. 27 CFR 46.261 - Purpose of an alternate method or procedure.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Alternate Methods Or Procedures § 46.261...

  15. 27 CFR 46.274 - Penalties for failure to comply.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Ttb Authorities § 46.274 Penalties for failure to comply. If...

  16. 27 CFR 46.254 - Additional reasons for filing a claim.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Claims § 46.254 Additional reasons for filing...

  17. 27 CFR 46.261 - Purpose of an alternate method or procedure.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Alternate Methods Or Procedures § 46.261...

  18. 27 CFR 46.254 - Additional reasons for filing a claim.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Claims § 46.254 Additional reasons for filing...

  19. 27 CFR 46.254 - Additional reasons for filing a claim.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Claims § 46.254 Additional reasons for filing...

  20. 27 CFR 46.261 - Purpose of an alternate method or procedure.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Alternate Methods Or Procedures § 46.261...

  1. 27 CFR 46.206 - Articles in a foreign trade zone.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Inventories § 46.206 Articles in a foreign...

  2. 27 CFR 46.261 - Purpose of an alternate method or procedure.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Alternate Methods Or Procedures § 46.261...

  3. 27 CFR 46.254 - Additional reasons for filing a claim.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Claims § 46.254 Additional reasons for filing...

  4. 27 CFR 46.274 - Penalties for failure to comply.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Ttb Authorities § 46.274 Penalties for failure to comply. If...

  5. 27 CFR 46.254 - Additional reasons for filing a claim.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Claims § 46.254 Additional reasons for filing...

  6. 27 CFR 46.206 - Articles in a foreign trade zone.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Inventories § 46.206 Articles in a foreign...

  7. 27 CFR 46.206 - Articles in a foreign trade zone.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Inventories § 46.206 Articles in a foreign...

  8. 27 CFR 46.274 - Penalties for failure to comply.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Ttb Authorities § 46.274 Penalties for failure to comply. If...

  9. 27 CFR 46.206 - Articles in a foreign trade zone.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Inventories § 46.206 Articles in a foreign...

  10. 27 CFR 46.261 - Purpose of an alternate method or procedure.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Alternate Methods Or Procedures § 46.261...

  11. A BASIS FOR MODIFYING THE TANK 12 COMPOSITE SAMPLING DESIGN

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shine, G.

    The SRR sampling campaign to obtain residual solids material from the Savannah River Site (SRS) Tank Farm Tank 12 primary vessel resulted in obtaining appreciable material in all 6 planned source samples from the mound strata but only in 5 of the 6 planned source samples from the floor stratum. Consequently, the design of the compositing scheme presented in the Tank 12 Sampling and Analysis Plan, Pavletich (2014a), must be revised. Analytical Development of SRNL statistically evaluated the sampling uncertainty associated with using various compositing arrays and splitting one or more samples for compositing. The variance of the simple meanmore » of composite sample concentrations is a reasonable standard to investigate the impact of the following sampling options. Composite Sample Design Option (a). Assign only 1 source sample from the floor stratum and 1 source sample from each of the mound strata to each of the composite samples. Each source sample contributes material to only 1 composite sample. Two source samples from the floor stratum would not be used. Composite Sample Design Option (b). Assign 2 source samples from the floor stratum and 1 source sample from each of the mound strata to each composite sample. This infers that one source sample from the floor must be used twice, with 2 composite samples sharing material from this particular source sample. All five source samples from the floor would be used. Composite Sample Design Option (c). Assign 3 source samples from the floor stratum and 1 source sample from each of the mound strata to each composite sample. This infers that several of the source samples from the floor stratum must be assigned to more than one composite sample. All 5 source samples from the floor would be used. Using fewer than 12 source samples will increase the sampling variability over that of the Basic Composite Sample Design, Pavletich (2013). Considering the impact to the variance of the simple mean of the composite sample concentrations, the recommendation is to construct each sample composite using four or five source samples. Although the variance using 5 source samples per composite sample (Composite Sample Design Option (c)) was slightly less than the variance using 4 source samples per composite sample (Composite Sample Design Option (b)), there is no practical difference between those variances. This does not consider that the measurement error variance, which is the same for all composite sample design options considered in this report, will further dilute any differences. Composite Sample Design Option (a) had the largest variance for the mean concentration in the three composite samples and should be avoided. These results are consistent with Pavletich (2014b) which utilizes a low elevation and a high elevation mound source sample and two floor source samples for each composite sample. Utilizing the four source samples per composite design, Pavletich (2014b) utilizes aliquots of Floor Sample 4 for two composite samples.« less

  12. 27 CFR 46.253 - Destruction of articles by a Presidentially-declared major disaster.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... MISCELLANEOUS REGULATIONS RELATING TO TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Claims § 46...

  13. 27 CFR 46.210 - Articles marked “not for sale” or “complimentary”.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... RELATING TO TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Inventories § 46.210 Articles marked...

  14. 27 CFR 46.205 - Guidelines to determine title to articles in transit.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... RELATING TO TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Inventories § 46.205 Guidelines to...

  15. 27 CFR 46.210 - Articles marked “not for sale” or “complimentary”.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... RELATING TO TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Inventories § 46.210 Articles marked...

  16. 27 CFR 46.253 - Destruction of articles by a Presidentially-declared major disaster.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... MISCELLANEOUS REGULATIONS RELATING TO TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Claims § 46...

  17. 27 CFR 46.253 - Destruction of articles by a Presidentially-declared major disaster.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... MISCELLANEOUS REGULATIONS RELATING TO TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Claims § 46...

  18. 27 CFR 46.210 - Articles marked “not for sale” or “complimentary”.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... RELATING TO TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Inventories § 46.210 Articles marked...

  19. 27 CFR 46.210 - Articles marked “not for sale” or “complimentary”.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... RELATING TO TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Inventories § 46.210 Articles marked...

  20. 27 CFR 46.253 - Destruction of articles by a Presidentially-declared major disaster.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... MISCELLANEOUS REGULATIONS RELATING TO TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Claims § 46...

  1. 27 CFR 46.205 - Guidelines to determine title to articles in transit.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... RELATING TO TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Inventories § 46.205 Guidelines to...

  2. 27 CFR 46.205 - Guidelines to determine title to articles in transit.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... RELATING TO TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Inventories § 46.205 Guidelines to...

  3. 27 CFR 46.206 - Articles in a foreign trade zone.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Inventories § 46.206 Articles in a foreign trade zone. If...

  4. 27 CFR 46.253 - Destruction of articles by a Presidentially-declared major disaster.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... MISCELLANEOUS REGULATIONS RELATING TO TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Claims § 46...

  5. 27 CFR 46.205 - Guidelines to determine title to articles in transit.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... RELATING TO TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Inventories § 46.205 Guidelines to...

  6. 27 CFR 46.205 - Guidelines to determine title to articles in transit.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... RELATING TO TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Inventories § 46.205 Guidelines to...

  7. 27 CFR 46.210 - Articles marked “not for sale” or “complimentary”.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... RELATING TO TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Inventories § 46.210 Articles marked...

  8. 18. FLOOR PLAN AND SECTION DRAWING OF POWERHOUSE FOUNDATION AND ...

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

    18. FLOOR PLAN AND SECTION DRAWING OF POWERHOUSE FOUNDATION AND DRAFT TUBE Power House Plan and Sections, drawing E-965. Prepared by the Washington Water Power Company, December 27, 1922, revised January 5, 1926. - Enloe Dam, Power House, On Similkameen River, Oroville, Okanogan County, WA

  9. 27 CFR 46.201 - General.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... TREASURY (CONTINUED) TOBACCO MISCELLANEOUS REGULATIONS RELATING TO TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for... the method to use for each to determine quantities: Article Inventory method Small cigarettes Count...

  10. 27 CFR 46.252 - Claim based on error on return.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Claims § 46.252 Claim based on error on return. If the dealer...

  11. 27 CFR 46.201 - General.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... TREASURY (CONTINUED) TOBACCO MISCELLANEOUS REGULATIONS RELATING TO TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for... the method to use for each to determine quantities: Article Inventory method Small cigarettes Count...

  12. 27 CFR 46.252 - Claim based on error on return.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Claims § 46.252 Claim based on error on return. If the dealer...

  13. 27 CFR 46.201 - General.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... TREASURY (CONTINUED) TOBACCO MISCELLANEOUS REGULATIONS RELATING TO TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for... the method to use for each to determine quantities: Article Inventory method Small cigarettes Count...

  14. 27 CFR 46.201 - General.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... TREASURY (CONTINUED) TOBACCO MISCELLANEOUS REGULATIONS RELATING TO TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for... the method to use for each to determine quantities: Article Inventory method Small cigarettes Count...

  15. 27 CFR 46.252 - Claim based on error on return.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Claims § 46.252 Claim based on error on return. If the dealer...

  16. 27 CFR 46.201 - General.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... TREASURY (CONTINUED) TOBACCO MISCELLANEOUS REGULATIONS RELATING TO TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for... the method to use for each to determine quantities: Article Inventory method Small cigarettes Count...

  17. 27 CFR 46.252 - Claim based on error on return.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Claims § 46.252 Claim based on error on return. If the dealer...

  18. 27 CFR 46.252 - Claim based on error on return.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Claims § 46.252 Claim based on error on return. If the dealer...

  19. Pre-fired, refractory block slag dams for wet bottom furnace floors

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Vihnicka, R.S.; Meskimen, R.L.

    1998-12-31

    Slagging (wet bottom), utility boilers count on a refractory coating over the furnace floor tube structure for protection from corrosion damage from both the harsh, hot gas atmosphere from the burning fuel and the acidic coal slag. To protect and extend the life of this protective refractory coating the boiler original equipment manufacturers (OEMs) utilized a water-cooled monkey ring or slag chill ring (typically a 6--8 inch high ring of small diameter tubes) surrounding the slag tap locations on most wet bottom furnace floors (both utility and package boilers). The old water-cooled tube ring was such a high maintenance item,more » however, that it`s use has been discontinued in all but the most extreme environments throughout both utility and industrial applications. Where the use of the ring was discontinued, there has been a corresponding shortening of life on the protective floor refractory coatings (high maintenance cost), further aggravated by recent OSHA restrictions limiting the use of chrome oxide refractory materials in these types of boilers. This paper describes the developmental process and the final resultant product (a non-watercooled, slag dam made from pre-fired refractory shapes), undertaken by the inventors. Derived operational benefits a concept 2 project, with NO{sub x} Title 4 and Title 1 significance (which is currently underway) will also be detailed.« less

  20. Searching for pelvic floor muscle exercises on YouTube: what individuals may find and where this might fit with health service programmes to promote continence.

    PubMed

    Stephen, Kate; Cumming, Grant P

    2012-09-01

    This paper describes the investigation, categorization/characterization and viewing of pelvic floor muscle exercises (PFME) on YouTube from the perspective of the 'wisdom of the crowd'. The aim of the research was to increase awareness of the type of clips that individuals are likely to come across when searching YouTube and to describe trends and popularity. This awareness will be useful for the design of continence promotion services, especially for hard-to-reach individuals. Web-based videos relating to PFE were identified by searching YouTube using the snowball technique. Main outcome measures Number of views; the approach taken (health, fitness, sexual and pregnancy); product promotion; and the use of music, visual cues and elements designed to encourage exercise. The number of views of each video was recorded at three points over a seven-month period. Twenty-two videos were identified. Overall these videos had been viewed over 430,000 times during the study period. One video was viewed over 100,000 times and overall the median increase in views was 59.4%. YouTube is increasingly used to access information about pelvic floor exercises. Different approaches are used to communicate PFME information but there are no formal structures for quality control. Further research is required to identify which elements of the video clips are effective in communicating information and in motivating exercise and to establish appropriate protocols. Kitemarking is recommended in order that women obtain correct advice.

  1. Pneumatic vacuum tube message center, basement room 23, looking southeast ...

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

    Pneumatic vacuum tube message center, basement room 23, looking southeast toward doorway and corridor. Note soundproof walls, pedestal flooring, and cable tray suspended from the ceiling - March Air Force Base, Strategic Air Command, Combat Operations Center, 5220 Riverside Drive, Moreno Valley, Riverside County, CA

  2. 27 CFR 46.222 - Determination of amount of tax due.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Tax Liability Calculation § 46.222... tax rate. Small cigarettes weighing not more than 3 pounds thousand Divide number of cigarettes by 1...

  3. 27 CFR 46.222 - Determination of amount of tax due.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Tax Liability Calculation § 46.222... tax rate. Small cigarettes weighing not more than 3 pounds thousand Divide number of cigarettes by 1...

  4. 27 CFR 46.222 - Determination of amount of tax due.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Tax Liability Calculation § 46.222... tax rate. Small cigarettes weighing not more than 3 pounds thousand Divide number of cigarettes by 1...

  5. 27 CFR 46.222 - Determination of amount of tax due.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Tax Liability Calculation § 46.222... tax rate. Small cigarettes weighing not more than 3 pounds thousand Divide number of cigarettes by 1...

  6. 27 CFR 46.222 - Determination of amount of tax due.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette Tubes Held for Sale on April 1, 2009 Tax Liability Calculation § 46.222... tax rate. Small cigarettes weighing not more than 3 pounds thousand Divide number of cigarettes by 1...

  7. THIRD LEVEL OF MISSILE LAB (SECOND FLOOR OF BUILDING) SHOWING ...

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

    THIRD LEVEL OF MISSILE LAB (SECOND FLOOR OF BUILDING) SHOWING MISSILE TUBE. VIEW FACING SOUTH - U.S. Naval Base, Pearl Harbor, Ford Island Polaris Missile Lab & U.S. Fleet Ballistic Missile Submarine Training Center, Between Lexington Boulvevard and the sea plane ramps on the southwest side of Ford Island, Pearl City, Honolulu County, HI

  8. VIEW OF EQUIPMENT AT THE GROUND FLOOR LEVEL OF THE ...

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

    VIEW OF EQUIPMENT AT THE GROUND FLOOR LEVEL OF THE MISSILE TUBE ROOM. VIEW FACING SOUTH - U.S. Naval Base, Pearl Harbor, Ford Island Polaris Missile Lab & U.S. Fleet Ballistic Missile Submarine Training Center, Between Lexington Boulvevard and the sea plane ramps on the southwest side of Ford Island, Pearl City, Honolulu County, HI

  9. View north of inside machine shop 36; shop floor accommodates ...

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

    View north of inside machine shop 36; shop floor accommodates lathes capable of machining a cylinder 60 inches in diameter and 75 feet long; other equipment includes horizontal and vertical jig borders, hydraulic tube straighteners and other equipment for precision machining of large ship components. - Naval Base Philadelphia-Philadelphia Naval Shipyard, Structure Shop, League Island, Philadelphia, Philadelphia County, PA

  10. VIEW OF CONTROL PANEL (RIGHT) AT THE GROUND FLOOR LEVEL ...

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

    VIEW OF CONTROL PANEL (RIGHT) AT THE GROUND FLOOR LEVEL AND SIDE OF THE MISSILE TUBE (FOREGROUND). VIEW FACING EAST - U.S. Naval Base, Pearl Harbor, Ford Island Polaris Missile Lab & U.S. Fleet Ballistic Missile Submarine Training Center, Between Lexington Boulvevard and the sea plane ramps on the southwest side of Ford Island, Pearl City, Honolulu County, HI

  11. Effects of the amount and composition of the forest floor on emergence and early establishment of loblolly pine seedlings

    Treesearch

    Michael G. Shelton

    1995-01-01

    Five forest floor weights (0, 10, 20, 30, and 40 MgJha), three forest floor compositions (pine, pine-hardwood, and hardwood), and two seed placements (forest floor and soil surface) were tested in a three-factorial. split-plot design with four incomplete, randomized blocks. The experiment was conducted in a nursery setting and used wooden frames to define 0.145-m

  12. USAF Dental Service Mercury Hygiene Report, Calendar Year 1980.

    DTIC Science & Technology

    1981-12-01

    the floor. Mercury Vapor Analyzer Used No. calibration No. of clinics Percent reported MV2 - Bacharach 81 67.5 14 Hopcalite tubes 8 6.7 Jerome model...instruments which could determine TWA: hopcalite tubes (8), Jerome with dosimeter coils (5), and 3M monitor (3). All 16 of these surveys showed mercury...vapor levels. This quantification requires sampling using the Jerome with a dosimeter coil, hopcalite tubes, or the 3M monitor. The USAF Occupational

  13. DETAIL OF MISSILE TUBE HATCH WITH MILLED FITTINGS AT GROUND ...

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

    DETAIL OF MISSILE TUBE HATCH WITH MILLED FITTINGS AT GROUND FLOOR LEVEL. VIEW FACING EAST - U.S. Naval Base, Pearl Harbor, Ford Island Polaris Missile Lab & U.S. Fleet Ballistic Missile Submarine Training Center, Between Lexington Boulvevard and the sea plane ramps on the southwest side of Ford Island, Pearl City, Honolulu County, HI

  14. 19. NORTH STAIRHALL (THERE ARE TWO FIRST FLOOR STAIRHALLS IN ...

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

    19. NORTH STAIRHALL (THERE ARE TWO FIRST FLOOR STAIRHALLS IN THE HOUSE, ONE IN THE WEST SECTION AND THE OTHER IN THE NORTH SECTION). NOTE ARTIFICALLY GRAINED DOOR SURROUND. ON THE WALL IS LATE NINETEENTH OR EARLY TWENTIETH CENTURY KNOB AND TUBE WIRING WITH ORIGINAL WOOD FUSE BOX. MODERN JUNCTION BOX IS AT LEFT. - Colonel McNeal House, Union & Bills Streets, Bolivar, Hardeman County, TN

  15. VIEW OF THIRD LEVEL OF MISSILE LAB (SECOND FLOOR OF ...

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

    VIEW OF THIRD LEVEL OF MISSILE LAB (SECOND FLOOR OF BUILDING) SHOWING MISSILE TUBE IN CENTER WITH OPEN HATCH AT RIGHT. VIEW FACING NORTHEAST - U.S. Naval Base, Pearl Harbor, Ford Island Polaris Missile Lab & U.S. Fleet Ballistic Missile Submarine Training Center, Between Lexington Boulvevard and the sea plane ramps on the southwest side of Ford Island, Pearl City, Honolulu County, HI

  16. Performance and quality-control standards for composite floor, wall, and truss framing

    Treesearch

    Gerald A. Koenigshof

    1985-01-01

    Users must be assured that composite structural members are satisfactory for their intended purposes. Standards are provided for strength, stiffness, durability, and dimensional stability of composite floor, wall, and truss-framing members. Methods for enforcing compliance with the standards are suggested.

  17. Impact evaluation of composite floor sections

    NASA Technical Reports Server (NTRS)

    Boitnott, Richard L.; Fasanella, Edwin L.

    1989-01-01

    Graphite-epoxy floor sections representative of aircraft fuselage construction were statically and dynamically tested to evaluate their response to crash loadings. These floor sections were fabricated using a frame-stringer design typical of present aluminum aircraft without features to enhance crashworthiness. The floor sections were tested as part of a systematic research program developed to study the impact response of composite components of increasing complexity. The ultimate goal of the research program is to develop crashworthy design features for future composite aircraft. Initially, individual frames of six-foot diameter were tested both statically and dynamically. The frames were then used to construct built-up floor sections for dynamic tests at impact velocities of approximately 20 feet/sec to simulate survivable crash velocities. In addition, static tests were conducted to gain a better understanding of the failure mechanisms seen in the dynamic tests.

  18. Solids Erosion Patterns Developed by Pulse Jet Mixers

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bamberger, Judith A.; Pease, Leonard F.; Minette, Michael J.

    Millions of gallons of radioactive waste are stored in underground storage tanks at the Hanford Site in Washington State. This waste will be vitrified at the Waste Treatment and Immobilization Plant that is under construction. Vessels in the pretreatment portion of the plant are being configured for processing waste slurries with challenging physical and rheological properties that range from Newtonian slurries to non-Newtonian sludge. Pulse jet mixing technology has been selected for mobilizing and mixing this waste. In the pulse jet mixing process, slurry is expelled from pulse tube nozzles directed towards the vessel floor. The expelled fluid forms amore » radial jet that erodes the settled layer of solids. The pulse tubes are configured in a ring or multiple rings and operate concurrently. The expelled fluid and mobilized solids traverse toward the center of the tank. At the tank center the jets from pulse tubes in the ring collide and lift solids upward in a central plume. At the end of the pulse, when the desired fluid volume is expelled from the pulse tube, the applied pressure switches to suction and the pulse tube is refilled. This cycle is used to mobilize and mix the tank contents. An initial step of the process is the erosion of solids from the vessel floor by the radial jets that form on the vessel flow beneath each pulse tube. Experiments have been conducted using simulants to evaluate the ability of the pulse jet mixing system radial jets to combine to develop the central upwell and lift solids into the vessel. These experiments have been conducted at three scales using a range of granular simulants over a range of concentrations. The vessels have elliptical, spherical, or flanged and dished bottoms. Process parameters evaluated include the velocity of fluid expelled from the pulse tube, the duration of the pulse and the duty cycle, the ratio of pulse duration to cycle time. Videos taken from beneath the vessel show the growth of the cleared area from each pulse tube as a function of time. All solids are lifted from the vessel bottom when the system is operating at the critical suspension velocity. The focus of this paper is to compare and contrast erosion patterns developed from different simulants and pulse tube configurations. The cases are evaluated to determine how changes in process parameters affects the PJM ability to mobilize solids from the vessel floor.« less

  19. 75 FR 42605 - Increase in Tax Rates on Tobacco Products and Cigarette Papers and Tubes; Floor Stocks Tax on...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-22

    ... than large cigars described in 26 U.S.C. 5701(a)(2)), and on cigarette papers and tubes, held for sale... tobacco for making cigars and tobacco for use as wrappers for cigars, effective April 1, 2009. The..., independent public health foundation, commented that TTB's large cigar reporting rules should be amended to...

  20. 61. photographer unknown undated FIRST CONCRETE BEING POURED IN DRAFT ...

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

    61. photographer unknown undated FIRST CONCRETE BEING POURED IN DRAFT TUBE FLOOR SLAB. - Bonneville Project, Powerhouse No.1, Spanning Bradford Slough, from Bradford Island, Bonneville, Multnomah County, OR

  1. Dynamic Testing of In-Situ Composite Floors and Evaluation of Vibration Serviceability Using the Finite Element Method

    DTIC Science & Technology

    2006-08-21

    Dynamic Testing of In-Situ Composite Floors and Evaluation of Vibration Serviceability Using the Finite Element Method By Anthony R. Barrett...Setareh Alfred L. Wicks 21 August 2006 Blacksburg, VA Keywords: vibration, floor, serviceability , walking, modal analysis, fundamental frequency...burden estimate or any other aspect of this collection of information, including suggestions for reducing this burden, to Washington Headquarters Services

  2. Modelling of concrete topping thickness effects on the vibration behaviour for lvl-concrete composite floor (LCC)

    NASA Astrophysics Data System (ADS)

    Ghafar, NH Abd; Sahban, N. M.

    2017-11-01

    This research was conducted on 2 m LVL - concrete composite (LCC) floor consisting of two parts between concrete floor and laminated veneer lumber (LVL) timber joist. The floor system was model using SAP 2000 software package. The aim of this research to study the vibration behaviour of the LCC floor with different concrete topping thickness which 25 mm, 65 mm and from 20 mm until 200 mm in every 20 mm interval. Natural frequency decision produced through SAP 2000 in thickness 25 mm and 65 mm is 57.45 Hz and 57.19 Hz. In thickness from 20 mm until 200 mm in every 20 mm interval, optimum value which found is during thickness reach 65 mm. For concrete topping below 65 mm thickness, the mass will be domain the behavior of the floor. When concrete topping increased more than 65 mm, the behavior of the floor will be domain by floor stiffness.

  3. Micro-shear bond strengths of adhesive resins to coronal dentin versus the floor of the pulp chamber.

    PubMed

    Toba, Shigemitsu; Veerapravati, Weeraporn; Shimada, Yasushi; Nikaido, Toru; Tagami, Junji

    2003-09-01

    To evaluate the micro-shear bond strengths to superficial coronal dentin and the floor of the pulp chamber using two dentin bonding systems and to compare the ultrastructure of the resin-dentin interface of the two regions. 30 non-carious molars were used to obtain 2 mm thick slabs of coronal dentin and dentin at the pulp chamber. The specimens in each region were divided into three sub-groups to be bonded as follows; Clearfil SE Bond was used according to the manufacturer's instructions, Single Bond was applied to either wet dentin (Blot dry Group) or air-dried dentin (Dry Group) after phosphoric acid etching. A resin composite cylinder 0.5 mm high and 0.75 mm in diameter formed using a vinyl tube was bonded to the dentin. Specimens were stored at 37 degrees C for 24 hours in water and then stressed in shear at a crosshead speed of 1 mm/minute. The data were analyzed with one-way ANOVA and Fisher's PLSD test at the 5% level of significance. In addition, the ultrastructure of cross-sectioned dentin surfaces, the conditioned dentin surface and the resin dentin interfaces were observed by SEM. The bond strengths of Clearfil SE Bond and the Single Bond Blot dry group were approximately 40 MPa in coronal dentin and 30 MPa in the dentin at the floor of the pulp chamber respectively. However, the bond strengths of Single Bond were significantly lower in the Dry condition (MPa) (P < 0.05). SEM observations revealed the thickness of the hybrid layer created by Clearfil SE Bond in coronal dentin and at the floor of the pulp chamber were less than 1.0 microm thick. For Single Bond, a 3-4 microm hybrid layer was created in coronal dentin, while a thinner hybrid layer was observed in the floor of the pulp chamber. Morphological and structural variations in dentin may have influenced the bond strengths of the bonding systems to the floor of the pulp chamber.

  4. Experimental Research of FRP Composite Tube Confined Steel-reinforced Concrete Stub Columns Under Axial Compression

    NASA Astrophysics Data System (ADS)

    Wang, Ji Zhong; Cheng, Lu; Wang, Xin Pei

    2018-06-01

    A new column of FRP composite tube confined steel-reinforced concrete (FTCSRC) column was proposed. This paper elaborates on laboratorial and analytical studies on the behavior of FCTSRC columns subjected to axial compressive load. Eight circular FTCSRC stub columns and one circular steel tube confined concrete (STCC) stub column were tested to investigate the failure mode and axial compression performance of circular FTCRSC columns. Parametric analysis was implemented to inquire the influence of confinement material (CFRP-steel tube or CFRP-GFRP tube), internal steel and CFRP layers on the ultimate load capacity. CFRP-steel composite tube was composed of steel tube and CFRP layer which was wrapped outside the steel tube, while CFRP-GFRP composite tube was composite of GFRP tube and CFRP layer. The test results indicate that the confinement effect of CFRP-steel tube is greatly superior to CFRP-GFRP tube. The ductility performance of steel tube confined high-strength concrete column can be improved obviously by encasing steel in the core concrete. Furthermore, with the increase in the layers of FRP wraps, the axial load capacity increases greatly.

  5. Finite Element Models and Properties of a Stiffened Floor-Equipped Composite Cylinder

    NASA Technical Reports Server (NTRS)

    Grosveld, Ferdinand W.; Schiller, Noah H.; Cabell, Randolph H.

    2010-01-01

    Finite element models were developed of a floor-equipped, frame and stringer stiffened composite cylinder including a coarse finite element model of the structural components, a coarse finite element model of the acoustic cavities above and below the beam-supported plywood floor, and two dense models consisting of only the structural components. The report summarizes the geometry, the element properties, the material and mechanical properties, the beam cross-section characteristics, the beam element representations and the boundary conditions of the composite cylinder models. The expressions used to calculate the group speeds for the cylinder components are presented.

  6. 60. photographer unknown undated CONCRETE BEING POURED ON CENTER PORTION ...

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

    60. photographer unknown undated CONCRETE BEING POURED ON CENTER PORTION OF DRAFT TUBE FLOOR SLAB. - Bonneville Project, Powerhouse No.1, Spanning Bradford Slough, from Bradford Island, Bonneville, Multnomah County, OR

  7. About GI Motility

    MedlinePlus

    ... eNewsletter Sidebar × MOBILE MENU About Us Learn About GI Motility Digestive Tract Disorders of the Esophagus Disorders ... Floor Motility Testing Personal Stories Contact Search About GI Motility Twitter Facebook YouTube Search Search ... About Us ...

  8. Learn About GI Motility

    MedlinePlus

    ... eNewsletter Sidebar × MOBILE MENU About Us Learn About GI Motility Digestive Tract Disorders of the Esophagus Disorders ... Floor Motility Testing Personal Stories Contact Search About GI Motility Twitter Facebook YouTube Search Search ... About Us ...

  9. 27 CFR 46.241 - Required records.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette... all controlled group members, if applicable; (d) A copy of the tax return, if the dealer filed one; (e...

  10. Polymer dynamics: Floored by the rings

    NASA Astrophysics Data System (ADS)

    McLeish, Tom

    2008-12-01

    The tube model can explain how mutually entangled polymer chains move and interact, but it relies on the loose ends of chains to generate relaxation. Ring polymers have no ends - so how do they relax?

  11. 27 CFR 46.241 - Required records.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette... all controlled group members, if applicable; (d) A copy of the tax return, if the dealer filed one; (e...

  12. 27 CFR 46.241 - Required records.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette... all controlled group members, if applicable; (d) A copy of the tax return, if the dealer filed one; (e...

  13. 27 CFR 46.241 - Required records.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette... all controlled group members, if applicable; (d) A copy of the tax return, if the dealer filed one; (e...

  14. 27 CFR 46.241 - Required records.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette... all controlled group members, if applicable; (d) A copy of the tax return, if the dealer filed one; (e...

  15. Organic contaminant separator

    DOEpatents

    Del Mar, P.

    1993-12-28

    A process is presented of sample preparation prior to analysis for the concentration of an organic contaminant in an aqueous medium by (a) passing an initial aqueous medium including a minor amount of the organic contaminant through a composite tube comprised of a blend of a polyolefin and a polyester, the composite tube having an internal diameter of from about 0.1 to about 2.0 millimeters and being of sufficient length to permit the organic contaminant to adhere to the composite tube, (b) passing a solvent through the composite tube. The solvent is capable of separating the adhered organic contaminant from the composite tube. Further, an extraction apparatus is presented for sample preparation prior to analysis for the concentration of an organic contaminant in an aqueous medium. The apparatus includes a composite tube comprised of a blend of a polyolefin and a polyester. The composite tube has an internal diameter of from about 0.1 to about 2.0 millimeters and has sufficient length to permit an organic contaminant contained within an aqueous medium passed therethrough to adhere to the composite tube. 2 figures.

  16. 27 CFR 46.263 - Conditions for approval.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette... any provision of law; (e) It will not result in an increase in cost to the Government; (f) It will not...

  17. 27 CFR 46.234 - Tax payment deadline.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette... Public Law 111-3 specifies a tax payment deadline of August 1, 2009. However, section 5703(b)(2)(E) of...

  18. 27 CFR 46.263 - Conditions for approval.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette... any provision of law; (e) It will not result in an increase in cost to the Government; (f) It will not...

  19. 27 CFR 46.234 - Tax payment deadline.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette... Public Law 111-3 specifies a tax payment deadline of August 1, 2009. However, section 5703(b)(2)(E) of...

  20. 27 CFR 46.263 - Conditions for approval.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette... any provision of law; (e) It will not result in an increase in cost to the Government; (f) It will not...

  1. 27 CFR 46.234 - Tax payment deadline.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette... Public Law 111-3 specifies a tax payment deadline of August 1, 2009. However, section 5703(b)(2)(E) of...

  2. 27 CFR 46.234 - Tax payment deadline.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette... Public Law 111-3 specifies a tax payment deadline of August 1, 2009. However, section 5703(b)(2)(E) of...

  3. 27 CFR 46.234 - Tax payment deadline.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette... Public Law 111-3 specifies a tax payment deadline of August 1, 2009. However, section 5703(b)(2)(E) of...

  4. 27 CFR 46.263 - Conditions for approval.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette... any provision of law; (e) It will not result in an increase in cost to the Government; (f) It will not...

  5. 27 CFR 46.263 - Conditions for approval.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... CIGARETTE PAPERS AND TUBES Floor Stocks Tax on Certain Tobacco Products, Cigarette Papers, and Cigarette... any provision of law; (e) It will not result in an increase in cost to the Government; (f) It will not...

  6. Buckling of thin walled composite cylindrical shell filled with solid propellant

    NASA Astrophysics Data System (ADS)

    Dash, A. P.; Velmurugan, R.; Prasad, M. S. R.

    2017-12-01

    This paper investigates the buckling of thin walled composite cylindrical tubes that are partially filled with solid propellant equivalent elastic filler. Experimental investigation is conducted on thin composite tubes made out of S2-glass epoxy, which is made by using filament winding technique. The composite tubes are filled with elastic filler having similar mechanical properties as that of a typical solid propellant used in rocket motors. The tubes are tested for their buckling strength against the external pressure in the presence of the filler. Experimental data confirms the enhancement of external pressure carrying capacity of the composite tubes by up to three times as that of empty tubes for a volumetric loading fraction (VLF) of 0.9. Furthermore, the finite element based geometric nonlinearity analysis predicts the buckling behaviour of the partially filled composite tubes close to the experimental results.

  7. Injury to endoscopic personnel from tripping over exposed cords, wires, and tubing in the endoscopy suite: a preventable cause of potentially severe workplace injury.

    PubMed

    Cappell, Mitchell S

    2010-04-01

    BACKGROUND The endoscopy unit before remediation may be a high-risk area for slip and fall injuries due to a large number of exposed above-the-floor wires in the endoscopy rooms, dimmed lighting during endoscopic procedures, and staff inattention to obstacles due to preoccupation with the endoscopic patient. AIM To describe a novel, previously unappreciated workplace hazard to endoscopic personnel: Exposed wires in the endoscopy unit.METHODS This study is a retrospective review of 110,000 endoscopic procedures performed during the last 5 years at an academic, teaching hospital with a high-volume endoscopy unit. All significant orthopedic injuries to endoscopic personnel from slips, twists, and falls from tripping over exposed cords in the endoscopy unit were reviewed. The severity of injury was documented based on roentgenographic findings, number of days of missed work, number of days with a modified work schedule, and requirement for orthopedic surgery. The number of potentially exposed cords per endoscopy room was determined. RESULTS During the 5-year study period, three endoscopic personnel suffered significant orthopedic injuries from slips, twists, and falls from tripping over cords, wires, or tubing lying exposed over the floor in the endoscopy suite: The resulting injuries consisted of fourth and fifth metacarpal hand fractures due to a fall after tripping on oxygen tubing; a rib fracture due to tripping on electrical wires trailing from an endoscopy cart; and a grade II ankle sprain due to the foot becoming entangled in oxygen tubing. All injuries resulted in lost days of work [mean 9.3 +/- 11.0 (SD) days] and in additional days of restricted work (mean 41.7 +/- 31.8 days). One injury required orthopedic surgery. Hospital review revealed a mean of 35.3 +/- 7.5 cords, wires, or tubing per endoscopy procedure room, the majority of which were exposed above the floor before remediation (n = 10 rooms). Remediation of exposed wires included: bundling related wires together in a cable to reduce the number of independent wires, covering exposed wires on the floor with a nonslip heavy mat, and running wires from ceiling outlets to equipment high above ground (e.g. mounted endoscopy video monitors). CONCLUSIONS Tripping, slipping, and falling over exposed wires can cause significant injury to endoscopic personnel. This previously undescribed hazard should be preventable by simple remediation, and all endoscopic personnel, hospital architects, hospital administrators, and governmental regulators should be alerted to this potential hazard

  8. 29 CFR 1926.754 - Structural steel assembly.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... connectors on composite floors, roofs and bridge decks. When shear connectors are used in construction of composite floors, roofs and bridge decks, employees shall lay out and install the shear connectors after the... requirements of paragraph (e)(3)(i) of this section. (4) Decking gaps around columns. Wire mesh, exterior...

  9. 29 CFR 1926.754 - Structural steel assembly.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... connectors on composite floors, roofs and bridge decks. When shear connectors are used in construction of composite floors, roofs and bridge decks, employees shall lay out and install the shear connectors after the... requirements of paragraph (e)(3)(i) of this section. (4) Decking gaps around columns. Wire mesh, exterior...

  10. 29 CFR 1926.754 - Structural steel assembly.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... connectors on composite floors, roofs and bridge decks. When shear connectors are used in construction of composite floors, roofs and bridge decks, employees shall lay out and install the shear connectors after the... requirements of paragraph (e)(3)(i) of this section. (4) Decking gaps around columns. Wire mesh, exterior...

  11. Explosion interaction with water in a tube

    NASA Astrophysics Data System (ADS)

    Homae, T.; Sugiyama, Y.; Wakabayashi, K.; Matsumura, T.; Nakayama, Y.

    2017-02-01

    As proposed and legislated in Japan, subsurface magazines have an explosive storage chamber, a horizontal passageway, and a vertical shaft for a vent. The authors found that a small amount of water on the floor of the storage chamber mitigated blast pressure remarkably. The mitigation mechanism has been examined more closely. To examine the effect of water, the present study assesses explosions in a transparent, square cross section, and a straight tube. A high-speed camera used to observe the tube interior. Blast pressure in and around the tube was also measured. Images obtained using the high-speed camera revealed that water inside the tube did not move after the explosion. Differences between cases of tubes without water and with water were unclear. Along with blast pressure measurements, these study results suggest that blast pressure mitigation by water occurs because of interaction between the explosion and the water near the explosion point.

  12. Effect of incremental filling technique on adhesion of light-cured resin composite to cavity floor.

    PubMed

    Chikawa, Hirokazu; Inai, Norimichi; Cho, Eitetsu; Kishikawa, Ryuzo; Otsuki, Masayuki; Foxton, Richard M; Tagami, Junji

    2006-09-01

    The purpose of this study was to evaluate the effect of various incremental filling techniques on adhesion between composite and cavity floor using light-cured resin composite. Black ABS resin and hybrid resin composite were used as mold materials--instead of dentin--for the preparation of cavities, and standardized to 5x5x5 mm. Each cavity was then treated with a bonding system (Clearfil SE bond). Resin composite (Clearfil Photo Core) was placed on the bonding resin using different incremental filling techniques or in bulk and irradiated for a total of 80 seconds using a halogen light unit. Specimens were subjected to the micro-tensile bond test at a crosshead speed of 1 mm/min. Data were analyzed by two-way ANOVA. The results indicated that an incremental filling technique was more effective in improving adhesion to the cavity floor than a bulk filling technique.

  13. Organic containment separator

    DOEpatents

    Del Mar, Peter

    1995-01-01

    A process of sample preparation prior to analysis for the concentration of an organic contaminant in an aqueous medium by (a) passing an initial aqueous medium including a minor amount of the organic contaminant through a composite tube including a polymeric base material selected from the group of polyolefins and polyfluorocarbons and particles of a carbon allotrope material adfixed to the inner wall of the polymeric base material, the composite tube having an internal diameter of from about 0.1 to about 2.0 millimeters and being of sufficient length to permit the organic contaminant to adhere to the composite tube, (b) passing a solvent through the composite tube, said solvent capable of separating the adhered organic contaminant from the composite tube. Further, an extraction apparatus for sample preparation prior to analysis for the concentration of an organic contaminant in an aqueous medium, said apparatus including a composite tube including a polymeric base material selected from the group of polyolefins and polyfluorocarbons and particles of a carbon allotrope material adfixed to the inner wall of the polymeric base material, the composite tube having an internal diameter of from about 0.1 to about 2.0 millimeters and being of sufficient length to permit an organic contaminant contained within an aqueous medium passed therethrough to adhere to the composite tube is disclosed.

  14. Organic contaminant separator

    DOEpatents

    Mar, Peter D.

    1994-01-01

    A process of sample preparation prior to analysis for the concentration of an organic contaminant in an aqueous medium by (a) passing an initial aqueous medium including a minor amount of the organic contaminant through a composite tube including a polymeric base material selected from the group of polyolefins and polyfluorocarbons and particles of a carbon allotrope material adfixed to the inner wall of the polymeric base material, the composite tube having an internal diameter of from about 0.1 to about 2.0 millimeters and being of sufficient length to permit the organic contaminant to adhere to the composite tube, (b) passing a solvent through the composite tube, said solvent capable of separating the adhered organic contaminant from the composite tube. Further, an extraction apparatus for sample preparation prior to analysis for the concentration of an organic contaminant in an aqueous medium, said apparatus including a composite tube including a polymeric base material selected from the group of polyolefins and polyfluorocarbons and particles of a carbon allotrope material adfixed to the inner wall of the polymeric base material, the composite tube having an internal diameter of from about 0.1 to about 2.0 millimeters and being of sufficient length to permit an organic contaminant contained within an aqueous medium passed therethrough to adhere to the composite tube is disclosed.

  15. Drum tie-down apparatus

    DOEpatents

    Morse, H.E.

    A drum tie-down apparatus for securing drum-like containers in an upright position to a floor or platform of a transportation vehicle having spaced apart cargo tie-down points. The apparatus comprises a pair of cylindrical, hollow tube segments horizontally oriented and engageable with a drum lid adjacent opposite rim edges, flexible strap segments for connecting upper and lower central portions of the tube segments together across the drum lid and a pair of elongated flexible tie-down segments, one extending horizontally through each of the tube segments, the ends thereof being attached to said spaced apart tie-down points such that end portions of the pair of tie-down segments extend downwardly and radially outwardly from the tube segments to the tie-down points.

  16. Drum tie-down apparatus

    DOEpatents

    Morse, Harvey E.

    1984-01-01

    A drum tie-down apparatus for securing drum-like containers in an upright position to a floor or platform of a transportation vehicle having spaced apart cargo tie-down points. The apparatus comprises a pair of cylindrical, hollow tube segments horizontally oriented and engageable with a drum lid adjacent opposite rim edges, flexible strap segments for connecting upper and lower central portions of the tube segments together across the drum lid and a pair of elongated flexible tie-down segments, one extending horizontally through each of the tube segments, the ends thereof being attached to said spaced apart tie-down points such that end portions of the pair of tie-down segments extend downwardly and radially outwardly from the tube segments to the tie-down points.

  17. Soil organic matter composition and quality across fire severity gradients in coniferous and deciduous forests of the southern boreal region

    NASA Astrophysics Data System (ADS)

    Miesel, Jessica R.; Hockaday, William C.; Kolka, Randall K.; Townsend, Philip A.

    2015-06-01

    Recent patterns of prolonged regional drought in southern boreal forests of the Great Lakes region, USA, suggest that the ecological effects of disturbance by wildfire may become increasingly severe. Losses of forest soil organic matter (SOM) during fire can limit soil nutrient availability and forest regeneration. These processes are also influenced by the composition of postfire SOM. We sampled the forest floor layer (i.e., full organic horizon) and 0-10 cm mineral soil from stands dominated by coniferous (Pinus banksiana Lamb.) or deciduous (Populus tremuloides Michx.) species 1-2 months after the 2011 Pagami Creek wildfire in northern Minnesota. We used solid-state 13C NMR to characterize SOM composition across a gradient of fire severity in both forest cover types. SOM composition was affected by fire, even when no statistically significant losses of total C stocks were evident. The most pronounced differences in SOM composition between burned and unburned reference areas occurred in the forest floor for both cover types. Carbohydrate stocks in forest floor and mineral horizons decreased with severity level in both cover types, whereas pyrogenic C stocks increased with severity in the coniferous forest floor and decreased in only the highest severity level in the deciduous forest floor. Loss of carbohydrate and lignin pools contributed to a decreased SOM stability index and increased decomposition index. Our results suggest that increases in fire severity expected to occur under future climate scenarios may lead to changes in SOM composition and dynamics with consequences for postfire forest recovery and C uptake.

  18. Control of formaldehyde and TVOC emission from wood-based flooring composites at various manufacturing processes by surface finishing.

    PubMed

    Kim, Sumin

    2010-04-15

    This paper assesses the reproducibility of testing formaldehyde and TVOC emission behavior from wood flooring composites bonded by urea-formaldehyde resin at various manufacturing steps for surface finishing materials. The surface adhesion step of laminate flooring for this research was divided into two steps; HDF only and HDF with LPMs. In the case of engineered flooring, the manufacturing steps were divided into three steps; plywood only, fancy veneer bonded on plywood and UV coated on fancy veneer with plywood. Formaldehyde and VOCs emission decreased at the process of final surface finishing materials; LPMs were applied on the surface of HDF for laminate flooring. Although emissions increased when fancy veneer was bonded onto plywood in the case of engineered flooring, emission was dramatically reduced up to similar level with plywood only when final surface finishing; UV-curable coating was applied on fancy veneer. This study suggests that formaldehyde and VOCs emission from floorings can be controlled at manufacturing steps for surface finishing. 2009 Elsevier B.V. All rights reserved.

  19. Gut microbiota composition is correlated to grid floor induced stress and behavior in the BALB/c mouse.

    PubMed

    Bangsgaard Bendtsen, Katja Maria; Krych, Lukasz; Sørensen, Dorte Bratbo; Pang, Wanyong; Nielsen, Dennis Sandris; Josefsen, Knud; Hansen, Lars H; Sørensen, Søren J; Hansen, Axel Kornerup

    2012-01-01

    Stress has profound influence on the gastro-intestinal tract, the immune system and the behavior of the animal. In this study, the correlation between gut microbiota composition determined by Denaturing Grade Gel Electrophoresis (DGGE) and tag-encoded 16S rRNA gene amplicon pyrosequencing (454/FLX) and behavior in the Tripletest (Elevated Plus Maze, Light/Dark Box, and Open Field combined), the Tail Suspension Test, and Burrowing in 28 female BALB/c mice exposed to two weeks of grid floor induced stress was investigated. Cytokine and glucose levels were measured at baseline, during and after exposure to grid floor. Stressing the mice clearly changed the cecal microbiota as determined by both DGGE and pyrosequencing. Odoribacter, Alistipes and an unclassified genus from the Coriobacteriaceae family increased significantly in the grid floor housed mice. Compared to baseline, the mice exposed to grid floor housing changed the amount of time spent in the Elevated Plus Maze, in the Light/Dark Box, and burrowing behavior. The grid floor housed mice had significantly longer immobility duration in the Tail Suspension Test and increased their number of immobility episodes from baseline. Significant correlations were found between GM composition and IL-1α, IFN-γ, closed arm entries of Elevated Plus Maze, total time in Elevated Plus Maze, time spent in Light/Dark Box, and time spent in the inner zone of the Open Field as well as total time in the Open Field. Significant correlations were found to the levels of Firmicutes, e.g. various species of Ruminococccaceae and Lachnospiraceae. No significant difference was found for the evaluated cytokines, except an overall decrease in levels from baseline to end. A significant lower level of blood glucose was found in the grid floor housed mice, whereas the HbA1c level was significantly higher. It is concluded that grid floor housing changes the GM composition, which seems to influence certain anxiety-related parameters.

  20. Low thermal flux glass-fiber tubing for cryogenic service

    NASA Technical Reports Server (NTRS)

    Hall, C. A.; Spond, D. E.

    1977-01-01

    This paper describes analytical techniques, fabrication development, and test results for composite tubing that has many applications in aerospace and commercial cryogenic installations. Metal liner fabrication is discussed in detail with attention given to resistance-welded liners, fusion-welded liners, chem-milled tubing liners, joining tube liners and end fittings, heat treatment and leak checks. Composite overwrapping, a second method of tubing fabrication, is also discussed. Test programs and analytical correlation are considered along with composite tubing advantages such as minimum weight, thermal efficiency and safety and reliability.

  1. Measurement of Full Field Strains in Filament Wound Composite Tubes Under Axial Compressive Loading by the Digital Image Correlation (DIC) Technique

    DTIC Science & Technology

    2013-05-01

    Measurement of Full Field Strains in Filament Wound Composite Tubes Under Axial Compressive Loading by the Digital Image Correlation (DIC...of Full Field Strains in Filament Wound Composite Tubes Under Axial Compressive Loading by the Digital Image Correlation (DIC) Technique Todd C...Wound Composite Tubes Under Axial Compressive Loading by the Digital Image Correlation (DIC) Technique 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c

  2. The Bottom Line For Air Quality.

    ERIC Educational Resources Information Center

    Ellis, Tom

    2000-01-01

    Discusses how the right type of flooring can help schools reduce indoor-air-quality problems. Using vinyl composition flooring to handle moisture and reduce fungi growth is examined as are the benefits of vinyl cushion tufted textile flooring for cost effectiveness, learning environment improvement, installation, and effectiveness in emergencies.…

  3. School Tucked in an Envelope.

    ERIC Educational Resources Information Center

    AIA Journal, 1981

    1981-01-01

    At the Telluride (Colorado) school, the classroom wing was outfitted with a thick floor slab and a greenhouse space where heat is stored in waterfilled tubes. The gymnasium's southwestern wall was transformed into a Trombe wall by applying 2,000 square feet of glazing. (Author/MLF)

  4. Mercury - the hollow planet

    NASA Astrophysics Data System (ADS)

    Rothery, D. A.

    2012-04-01

    Mercury is turning out to be a planet characterized by various kinds of endogenous hole (discounting impact craters), which are compared here. These include volcanic vents and collapse features on horizontal scales of tens of km, and smaller scale depressions ('hollows') associated with bright crater-floor deposits (BCFD). The BCFD hollows are tens of metres deep and kilometres or less across and are characteristically flat-floored, with steep, scalloped walls. Their form suggests that they most likely result from removal of surface material by some kind of mass-wasting process, probably associated with volume-loss caused by removal (via sublimation?) of a volatile component. These do not appear to be primarily a result of undermining. Determining the composition of the high-albedo bluish surface coating in BCFDs will be a key goal for BepiColombo instruments such as MIXS (Mercury Imaging Xray Spectrometer). In contrast, collapse features are non-circular rimless pits, typically on crater floors (pit-floor craters), whose morphology suggests collapse into void spaces left by magma withdrawal. This could be by drainage of either erupted lava (or impact melt) or of shallowly-intruded magma. Unlike the much smaller-scale BCFD hollows, these 'collapse pit' features tend to lack extensive flat floors and instead tend to be close to triangular in cross-section with inward slopes near to the critical angle of repose. The different scale and morphology of BCFD hollows and collapse pits argues for quite different modes of origin. However, BCFD hollows adjacent to and within the collapse pit inside Scarlatti crater suggest that the volatile material whose loss was responsible for the growth of the hollows may have been emplaced in association with the magma whose drainage caused the main collapse. Another kind of volcanic collapse can be seen within a 25 km-wide volcanic vent outside the southern rim of the Caloris basin (22.5° N, 146.1° E), on a 28 m/pixel MDIS NAC image from orbit. Although the vent itself may have been excavated partly by explosive volcanism, the most recent event is collapse of a 7 km wide zone in the south centre of the vent. The sharpness of features within this (unmuted either by regolith-forming processes or by fall of volcanic ejecta) suggests that this collapse considerably post-dates the rest of the vent interior. It could reflect a late-stage minor 'throat clearing' explosive eruption, but (in the absence of evidence of associated volcanic ejecta) more likely reflects collapse into a void within the volcanic conduit, itself a result of magma-drainage. A class of 'hole' that is so far conspicuous by its absence on Mercury is sinuous rilles (as opposed to much straighter tectonic grabens) or aligned skylights representing collapsed or partly-collapsed drained lava tubes. Tube-fed flows are to be expected during emplacement of volcanic plains, and it will be surprising if no examples are revealed on MESSENGER and BepiColombo high-resolution images.

  5. 76 FR 68366 - Airworthiness Directives; The Boeing Company Model 777-200 and -300 Series Airplanes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-04

    ...-induced currents and subsequent damage to composite structures, hydraulic tubes, and actuator control... and could subsequently damage composite structures, hydraulic tubes, and actuator control electronics... subsequent damage to composite structures, hydraulic tubes, and actuator control electronics. In the event of...

  6. Collector surface for a microwave tube comprising a carbon-bonded carbon-fiber composite

    DOEpatents

    Lauf, Robert J.; McMillan, April D.; Johnson, Arvid C.; Moorhead, Arthur J.

    1998-01-01

    In a microwave tube, an improved collector surface coating comprises a porous carbon composite material, preferably a carbon-bonded carbon fiber composite having a bulk density less than about 2 g/cc. Installation of the coating is readily adaptable as part of the tube manufacturing process.

  7. VIEW FROM THE PRODUCTION FLOOR OF BUILDING 460, LOOKING WEST. ...

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

    VIEW FROM THE PRODUCTION FLOOR OF BUILDING 460, LOOKING WEST. THE BUILDING 460 HOUSED EQUIPMENT, SYSTEMS, AND PERSONNEL FOR FABRICATION, ASSEMBLY, AND TESTING OF STAINLESS STEEL COMPONENTS SUCH AS RESERVOIRS, TUBES, AND NON-FISSILE TRIGGER COMPONENTS. THE PHOTOGRAPH SHOWS A T-BASED LATHE WITH AN OPTICAL COMPARITOR FOR MACHINING OF STAINLESS STEEL IN THE LOWER LEFT CORNER. THE DRUM IN THE LOWER RIGHT CORNER CONTAINS STAINLESS STEEL TURNING COLLECTED FROM THE LATHE. (9/11/85) - Rocky Flats Plant, Stainless Steel & Non-Nuclear Components Manufacturing, Southeast corner of intersection of Cottonwood & Third Avenues, Golden, Jefferson County, CO

  8. Collector surface for a microwave tube comprising a carbon-bonded carbon-fiber composite

    DOEpatents

    Lauf, R.J.; McMillan, A.D.; Johnson, A.C.; Moorhead, A.J.

    1998-07-28

    In a microwave tube, an improved collector surface coating comprises a porous carbon composite material, preferably a carbon-bonded carbon fiber composite having a bulk density less than about 2 g/cc. Installation of the coating is readily adaptable as part of the tube manufacturing process. 4 figs.

  9. Effects of Prenatal Exposure to Phthalates

    ERIC Educational Resources Information Center

    Johnson, Laurie A.

    2012-01-01

    The purpose of this review of literature is to examine the association of phthalate exposure with development. Phthalates are chemical compounds used in poly-vinyl chloride, PVC; vinyl flooring, cosmetics, shampoo, air fresheners, soft plastic items, intravenous tubing, food packaging and wraps, textiles, paints, cleaning products and detergents.…

  10. The Effects of Triggering Mechanisms on the Energy Absorption Capability of Circular Jute/Epoxy Composite Tubes under Quasi-Static Axial Loading

    NASA Astrophysics Data System (ADS)

    Sivagurunathan, Rubentheran; Lau Tze Way, Saijod; Sivagurunathan, Linkesvaran; Yaakob, Mohd. Yuhazri

    2018-01-01

    The usage of composite materials have been improving over the years due to its superior mechanical properties such as high tensile strength, high energy absorption capability, and corrosion resistance. In this present study, the energy absorption capability of circular jute/epoxy composite tubes were tested and evaluated. To induce the progressive crushing of the composite tubes, four different types of triggering mechanisms were used which were the non-trigger, single chamfered trigger, double chamfered trigger and tulip trigger. Quasi-static axial loading test was carried out to understand the deformation patterns and the load-displacement characteristics for each composite tube. Besides that, the influence of energy absorption, crush force efficiency, peak load, mean load and load-displacement history were examined and discussed. The primary results displayed a significant influence on the energy absorption capability provided that stable progressive crushing occurred mostly in the triggered tubes compared to the non-triggered tubes. Overall, the tulip trigger configuration attributed the highest energy absorption.

  11. Cladding material, tube including such cladding material and methods of forming the same

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Garnier, John E.; Griffith, George W.

    A multi-layered cladding material including a ceramic matrix composite and a metallic material, and a tube formed from the cladding material. The metallic material forms an inner liner of the tube and enables hermetic sealing of thereof. The metallic material at ends of the tube may be exposed and have an increased thickness enabling end cap welding. The metallic material may, optionally, be formed to infiltrate voids in the ceramic matrix composite, the ceramic matrix composite encapsulated by the metallic material. The ceramic matrix composite includes a fiber reinforcement and provides increased mechanical strength, stiffness, thermal shock resistance and highmore » temperature load capacity to the metallic material of the inner liner. The tube may be used as a containment vessel for nuclear fuel used in a nuclear power plant or other reactor. Methods for forming the tube comprising the ceramic matrix composite and the metallic material are also disclosed.« less

  12. Energy-absorption capability and scalability of square cross section composite tube specimens

    NASA Technical Reports Server (NTRS)

    Farley, Gary L.

    1987-01-01

    Static crushing tests were conducted on graphite/epoxy and Kevlar/epoxy square cross section tubes to study the influence of specimen geometry on the energy-absorption capability and scalability of composite materials. The tube inside width-to-wall thickness (W/t) ratio was determined to significantly affect the energy-absorption capability of composite materials. As W/t ratio decreases, the energy-absorption capability increases nonlinearly. The energy-absorption capability of Kevlar epoxy tubes was found to be geometrically scalable, but the energy-absorption capability of graphite/epoxy tubes was not geometrically scalable.

  13. Method for Identifying Lava Tubes Among Pit Craters Using Brightness Profile Across Pits on the Moon or Mars

    NASA Astrophysics Data System (ADS)

    Jung, Jongil; Hong, Ik-Seon; Cho, Eunjin; Yi, Yu

    2016-03-01

    Caves can serve as major outposts for future human exploration of the Moon and Mars. In addition, caves can protect people and electronic equipment from external hazards such as cosmic ray radiation and meteorites impacts and serve as a shelter. Numerous pit craters have been discovered on the Moon and Mars and are potential entrances to caves; the principal topographic features of pit craters are their visible internal floors and pits with vertical walls. We have devised two topographical models for investigating the relationship between the topographical characteristics and the inner void of pit craters. One of our models is a concave floor void model and the other is a convex floor tube model. For each model, optical photographs have been obtained under conditions similar to those in which optical photographs have been acquired for craters on the Moon and Mars. Brightness profiles were analyzed for determining the profile patterns of the void pit craters. The profile patterns were compared to the brightness profiles of Martian pit craters, because no good-quality images of lunar pit craters were available. In future studies, the model profile patterns will be compared to those of lunar pit craters, and the proposed method will likely become useful for finding lunar caves and consequently for planning lunar bases for manned lunar expeditions.

  14. 24 CFR 3280.802 - Definitions.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... protective devices or both, for the control of light, heat, or power circuits of small individual as well as... light, heat, or power circuits; designed to be placed in a cabinet or cutout box placed in or against a..., flexible metal conduit, electrical metallic tubing, underfloor raceways, cellular concrete floor raceways...

  15. 24 CFR 3280.802 - Definitions.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... protective devices or both, for the control of light, heat, or power circuits of small individual as well as... light, heat, or power circuits; designed to be placed in a cabinet or cutout box placed in or against a..., flexible metal conduit, electrical metallic tubing, underfloor raceways, cellular concrete floor raceways...

  16. Research on the Influence of Size Effect for the mechanical Performance of GFRP tube concrete steel tube composite column under axial compression

    NASA Astrophysics Data System (ADS)

    Li, Wen; Wang, Tong; Na, Yu

    2017-08-01

    FRP tube-concrete-steel tube composite column (DSTC) was a new type of composite structures. The column consists of FRP outer tube and steel tube and concrete. Concrete was filled between FRP outer tube and steel tube. This column has the character of light and high strength and corrosion resistance. In this paper, properties of DSTC axial compression were studied in depth. The properties were studied by two groups DSTC short columns under axial compression performance experiment. The different size of DSTC short columns was importantly considered. According to results of the experiment, we can conclude that with the size of the column increases the ability of it to resist deformation drops. On the other hand, the size effect influences on properties of different concrete strength DSTC was different. The influence of size effect on high concrete strength was less than that of low concrete.

  17. Analysis of Steel-With-Composite Material Substitution in Military Vehicle Hull Floors Subjected to Shallow-Buried Landmine-Detonation Loads

    DTIC Science & Technology

    2014-01-01

    vehicles/structures; in the work of Bergeron et al. (2002), an instrumented ballistic pendulum was utilized to investigate mine detonation-induced...element/ discrete-particle computational analysis in order to investigate potential benefits and drawbacks associated with material substitution...investigate potential benefits and drawbacks associated with material substitution (from steel to composite) in military-vehicle hull-floors whose primary

  18. Synthesis and characterization of a novel tube-in-tube nanostructured PPy/MnO{sub 2}/CNTs composite for supercapacitor

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Li, Juan, E-mail: lj-panpan@163.com; Beijing National Laboratory for Molecular Sciences; Que, Tingli

    2013-02-15

    Graphical abstract: A novel tube-in-tube nanostructured PPy/MnO{sub 2}/CNTs composite have been successfully fabricated. Its inner tubules are CNTs and the outer tubules are template-synthesized PPy. Most MnO{sub 2} nanoparticles are sandwiched between the inner and outer wall, some relatively large particles are also latched onto the outside wall of the PPy tube. The composite yields a good electrochemical reversibility through 1000 cycles’ cyclic voltammogram (CV) test and galvanostatic charge–discharge experiments at different current densities. Display Omitted Highlights: ► We fabricate a ternary organic–inorganic complex of PPy/MnO{sub 2}/CNTs composite. ► We characterize its morphological structures and properties by several techniques. ►more » The composite possesses the typical tube-in-tube nanostructures. ► Most MnO{sub 2} nanoparticles are sandwiched between the inner CNTs and outer PPy wall. ► The composite has good electrochemical reversibility for supercapacitor. -- Abstract: Ternary organic–inorganic complex of polypyrrole/manganese dioxide/carbon nanotubes (PPy/MnO{sub 2}/CNTs) composite was prepared by in situ chemical oxidation polymerization of pyrrole in the host of inorganic matrix of MnO{sub 2} and CNTs, using complex of methyl orange (MO)/FeCl{sub 3} was used as a reactive self-degraded soft-template. The morphological structures of the composite were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopic (HRTEM), Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD), respectively. All the results indicate that the PPy/MnO{sub 2}/CNTs composite possesses the typical tube-in-tube nanostructures: the inner tubules are CNTs and the outer tubules are template-synthesized PPy. MnO{sub 2} nanoparticles may either sandwich the space between the inner and outer tubules or directly latch onto the wall of the PPy tubes. The composite yields a good electrochemical reversibility through 1000 cycles’ cyclic voltammogram (CV) test in the potential range of −0.6 to 0.4 V and its specific capacitance was up to 402.7 F g{sup −1} at a current density of 1 A g{sup −1} in galvanostatic charge–discharge experiment.« less

  19. Fiber optic connector

    DOEpatents

    Rajic, Slobodan; Muhs, Jeffrey D.

    1996-01-01

    A fiber optic connector and method for connecting composite materials within which optical fibers are imbedded. The fiber optic connector includes a capillary tube for receiving optical fibers at opposing ends. The method involves inserting a first optical fiber into the capillary tube and imbedding the unit in the end of a softened composite material. The capillary tube is injected with a coupling medium which subsequently solidifies. The composite material is machined to a desired configuration. An external optical fiber is then inserted into the capillary tube after fluidizing the coupling medium, whereby the optical fibers are coupled.

  20. 78 FR 60766 - Clarification on Fireworks Policy Regarding Approvals or Certifications for Specialty Fireworks...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-02

    ... fireworks device is a fire truck with 10 tubes, 2 grams per tube, for a total pyrotechnic weight of 20 grams... fusing; 3. May not exceed 10 fiberboard or plastic tubes per device; 4. May not contain more than 2 grams of pyrotechnic composition per tube, and not more than 20 grams pyrotechnic composition in the...

  1. Adjustable-Pressure Mandrel For Making Composite Tubes

    NASA Technical Reports Server (NTRS)

    Jacoy, Paul J.; Schmitigal, Wesley P.

    1993-01-01

    Inflatable inner mandrel enables application of any desired pressure (within reasonable limits) during curing stage in fabrication of fiber/matrix composite tube. Consists mainly of sheath of silicone rubber sealed on aluminum tube. Composite material laid up on mandrel and enclosed in rigid outer die. Sheath on inner mandrel inflated to requisite pressure and regulated during curing. Assembly then placed in oven and cured at specified temperature.

  2. Absorption Of Crushing Energy In Square Composite Tubes

    NASA Technical Reports Server (NTRS)

    Farley, Gary L.

    1992-01-01

    Report describes investigation of crash-energy-absorbing capabilities of square-cross-section tubes of two matrix/fiber composite materials. Both graphite/epoxy and Kevlar/epoxy tubes crushed in progressive and stable manner. Ratio between width of cross section and thickness of wall determined to affect energy-absorption significantly. As ratio decreases, energy-absorption capability increases non-linearly. Useful in building energy-absorbing composite structures.

  3. Method for forming a liquid cooled airfoil for a gas turbine

    DOEpatents

    Grondahl, Clayton M.; Willmott, Leo C.; Muth, Myron C.

    1981-01-01

    A method for forming a liquid cooled airfoil for a gas turbine is disclosed. A plurality of holes are formed at spaced locations in an oversized airfoil blank. A pre-formed composite liquid coolant tube is bonded into each of the holes. The composite tube includes an inner member formed of an anti-corrosive material and an outer member formed of a material exhibiting a high degree of thermal conductivity. After the coolant tubes have been bonded to the airfoil blank, the airfoil blank is machined to a desired shape, such that a portion of the outer member of each of the composite tubes is contiguous with the outer surface of the machined airfoil blank. Finally, an external skin is bonded to the exposed outer surface of both the machined airfoil blank and the composite tubes.

  4. 27 CFR 46.209 - Articles in vending machines.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 2 2014-04-01 2014-04-01 false Articles in vending... Cigarette Tubes Held for Sale on April 1, 2009 Inventories § 46.209 Articles in vending machines. There is no exemption for articles in vending machines. They are subject to the floor stocks tax and must be...

  5. 27 CFR 46.243 - Articles at multiple locations.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 2 2010-04-01 2010-04-01 false Articles at multiple... Cigarette Tubes Held for Sale on April 1, 2009 Records § 46.243 Articles at multiple locations. The dealer must maintain a list of all places where the dealer holds articles subject to the floor stocks tax...

  6. 27 CFR 46.243 - Articles at multiple locations.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 2 2011-04-01 2011-04-01 false Articles at multiple... Cigarette Tubes Held for Sale on April 1, 2009 Records § 46.243 Articles at multiple locations. The dealer must maintain a list of all places where the dealer holds articles subject to the floor stocks tax...

  7. 27 CFR 46.204 - Articles in transit.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 2 2011-04-01 2011-04-01 false Articles in transit. 46... Tubes Held for Sale on April 1, 2009 Inventories § 46.204 Articles in transit. The dealer must include articles subject to floor stocks tax that are in transit in the inventory if the dealer holds title to...

  8. 27 CFR 46.243 - Articles at multiple locations.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 2 2014-04-01 2014-04-01 false Articles at multiple... Cigarette Tubes Held for Sale on April 1, 2009 Records § 46.243 Articles at multiple locations. The dealer must maintain a list of all places where the dealer holds articles subject to the floor stocks tax...

  9. 27 CFR 46.204 - Articles in transit.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 2 2014-04-01 2014-04-01 false Articles in transit. 46... Tubes Held for Sale on April 1, 2009 Inventories § 46.204 Articles in transit. The dealer must include articles subject to floor stocks tax that are in transit in the inventory if the dealer holds title to...

  10. 27 CFR 46.209 - Articles in vending machines.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 2 2012-04-01 2011-04-01 true Articles in vending... Cigarette Tubes Held for Sale on April 1, 2009 Inventories § 46.209 Articles in vending machines. There is no exemption for articles in vending machines. They are subject to the floor stocks tax and must be...

  11. 27 CFR 46.204 - Articles in transit.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 2 2010-04-01 2010-04-01 false Articles in transit. 46... Tubes Held for Sale on April 1, 2009 Inventories § 46.204 Articles in transit. The dealer must include articles subject to floor stocks tax that are in transit in the inventory if the dealer holds title to...

  12. 27 CFR 46.204 - Articles in transit.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 2 2013-04-01 2013-04-01 false Articles in transit. 46... Tubes Held for Sale on April 1, 2009 Inventories § 46.204 Articles in transit. The dealer must include articles subject to floor stocks tax that are in transit in the inventory if the dealer holds title to...

  13. 27 CFR 46.243 - Articles at multiple locations.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 2 2012-04-01 2011-04-01 true Articles at multiple... Cigarette Tubes Held for Sale on April 1, 2009 Records § 46.243 Articles at multiple locations. The dealer must maintain a list of all places where the dealer holds articles subject to the floor stocks tax...

  14. 27 CFR 46.209 - Articles in vending machines.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 2 2010-04-01 2010-04-01 false Articles in vending... Cigarette Tubes Held for Sale on April 1, 2009 Inventories § 46.209 Articles in vending machines. There is no exemption for articles in vending machines. They are subject to the floor stocks tax and must be...

  15. 27 CFR 46.209 - Articles in vending machines.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 2 2011-04-01 2011-04-01 false Articles in vending... Cigarette Tubes Held for Sale on April 1, 2009 Inventories § 46.209 Articles in vending machines. There is no exemption for articles in vending machines. They are subject to the floor stocks tax and must be...

  16. 27 CFR 46.243 - Articles at multiple locations.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 2 2013-04-01 2013-04-01 false Articles at multiple... Cigarette Tubes Held for Sale on April 1, 2009 Records § 46.243 Articles at multiple locations. The dealer must maintain a list of all places where the dealer holds articles subject to the floor stocks tax...

  17. 27 CFR 46.209 - Articles in vending machines.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 2 2013-04-01 2013-04-01 false Articles in vending... Cigarette Tubes Held for Sale on April 1, 2009 Inventories § 46.209 Articles in vending machines. There is no exemption for articles in vending machines. They are subject to the floor stocks tax and must be...

  18. 19. Interior first level view looking north within forward (north) ...

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

    19. Interior first level view looking north within forward (north) section of firing pier. Objects pictured include torpedo cart (left), floor-mounted roller tray (extending to lower right), and (at center rear), deck-type firing tube. - Naval Torpedo Station, Firing Pier, North end of Gould Island in Narragansett Bay, Newport, Newport County, RI

  19. W5 - If Pigs Could Fly

    NASA Astrophysics Data System (ADS)

    Cannon, Trina

    2012-10-01

    Centripetal force seems to be a challenge for students and we are typically using stoppers, string, tubes and slotted masses (that always crash to the floor). But if we use a toy that reminds them of an amusement park ride, we can get the message across and have some fun. Come and see if pigs can fly!

  20. The role of retinoic acid in the morphogenesis of the neural tube.

    PubMed

    Wilson, L; Gale, E; Maden, M

    2003-10-01

    We have examined the role of the signalling molecule, retinoic acid, in the process of neurulation and the subsequent growth and differentiation of the central nervous system using quail embryos that have developed in the absence of retinoic acid. Such retinoic acid-free embryos undergo abnormal neural tube formation in terms of its shape and structure, but the embryos do not display spina bifida or exencephaly. The neural tubes have a wider floor plate, a thicker roof plate and a different dorsoventral shape. Phalloidin staining and electron microscopy revealed alterations in the actin filaments and the junctional complexes of the cell layer lining the lumen. Initially the neural tubes proliferated at the same rate as normal, but later the proliferation rate declined drastically and neuronal differentiation was highly deficient. There were very few motoneurons extending neurites into the periphery, and within the neural tube axon trajectories were chaotic. These results reveal several functions for retinoic acid in the morphogenesis and growth of the neural tube, many of which can be explained by defective notochord signalling, but they do not suggest that this molecule plays a role in neural tube closure.

  1. Numerical Analysis of Prefabricated Steel-Concrete Composite Floor in Typical Lipsk Building

    NASA Astrophysics Data System (ADS)

    Lacki, Piotr; Kasza, Przemysław; Derlatka, Anna

    2017-12-01

    The aim of the work was to perform numerical analysis of a steel-concrete composite floor located in a LIPSK type building. A numerical model of the analytically designed floor was performed. The floor was in a six-storey, retail and service building. The thickness of a prefabricated slab was 100 mm. The two-row, crisscrossed reinforcement of the slab was made from φ16 mm rods with a spacing of 150 x 200 mm. The span of the beams made of steel IPE 160 profiles was 6.00 m and they were spaced every 1.20 m. The steelconcrete composite was obtained using 80×16 Nelson fasteners. The numerical analysis was carried out using the ADINA System based on the Finite Element Method. The stresses and strains in the steel and concrete elements, the distribution of the forces in the reinforcement bars and cracking in concrete were evaluated. The FEM model was made from 3D-solid finite elements (IPE profile and concrete slab) and truss elements (reinforcement bars). The adopted steel material model takes into consideration the plastic state, while the adopted concrete material model takes into account material cracks.

  2. Hydraulic Testing of Polymer Matrix Composite 102mm Tube Section Technical Report

    DTIC Science & Technology

    2018-04-01

    Technical Report ARWSB-TR-18025 Hydraulic Testing of Polymer Matrix Composite 102mm Tube Section Technical Report Lucas B...1. REPORT DATE (DD-MM-YYYY) April 2018 2. REPORT TYPE Technical 3. DATES COVERED (From - To) 4. TITLE AND SUBTITLE Hydraulic Testing of...Polymer Matrix Composite 102mm Tube Section Technical Report 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER

  3. The Physical Ocean.

    ERIC Educational Resources Information Center

    NatureScope, 1988

    1988-01-01

    Examines the physical properties of the ocean (including the composition of seawater; waves, currents, and tides) and the topography of the ocean floor. Included are (1) activities on oceans, saltwater, and the sea floor; and (2) questions, and a puzzle which can be copied. (Author/RT)

  4. Blast and Impact Resistant Composite Structures for Navy Ships

    DTIC Science & Technology

    2013-03-15

    Navy cargo ships, Air Force tactical shelters, Air Force runway matting, vehicular bridge decks, railcar floors and wind turbine blades. The US Army...bridge decks, railcar floors and wind turbine blades. NAVY RELEVANCE Producing stronger, safer and more cost-effective platforms for the new generation...floors and wind turbine blades. 32 NAVY RELEVANCE Producing stronger, safer and more cost-effective platforms for the new generation naval ships

  5. Fiber optic connector

    DOEpatents

    Rajic, S.; Muhs, J.D.

    1996-10-22

    A fiber optic connector and method for connecting composite materials within which optical fibers are imbedded are disclosed. The fiber optic connector includes a capillary tube for receiving optical fibers at opposing ends. The method involves inserting a first optical fiber into the capillary tube and imbedding the unit in the end of a softened composite material. The capillary tube is injected with a coupling medium which subsequently solidifies. The composite material is machined to a desired configuration. An external optical fiber is then inserted into the capillary tube after fluidizing the coupling medium, whereby the optical fibers are coupled. 3 figs.

  6. Preparation of pyrolysis reference samples: evaluation of a standard method using a tube furnace.

    PubMed

    Sandercock, P Mark L

    2012-05-01

    A new, simple method for the reproducible creation of pyrolysis products from different materials that may be found at a fire scene is described. A temperature programmable steady-state tube furnace was used to generate pyrolysis products from different substrates, including softwoods, paper, vinyl sheet flooring, and carpet. The temperature profile of the tube furnace was characterized, and the suitability of the method to reproducibly create pyrolysates similar to those found in real fire debris was assessed. The use of this method to create proficiency tests to realistically test an examiner's ability to interpret complex gas chromatograph-mass spectrometric fire debris data, and to create a library of pyrolsates generated from materials commonly found at a fire scene, is demonstrated. © 2011 American Academy of Forensic Sciences.

  7. Three-axis accelerometer package for slimhole and microhole seismic monitoring and surveys

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hunter, S.L.; Harben, P.E.

    1997-01-07

    The development of microdrilling technology, nominally defined as drilling technology for 1-in.-diameter boreholes, shows potential for reducing the cost of drilling monitoring wells. A major question that arises in drilling microholes is if downhole logging and monitoring in general--and downhole seismic surveying in particular--can be conducted in such small holes since the inner working diameter of such a seismic tool could be as small as 0.31 in. A downhole three-component accelerometer package that fits within a 031-in. inner diameter tube has been designed, built, and tested. The package consists of three orthogonally mounted Entran EGA-125-5g piezoresistive silicon micromachined accelerometers withmore » temperature compensation circuitry, downhole amplification, and line drivers mounted in a thin-walled aluminum tube. Accelerometers are commercially available in much smaller package sizes than conventional geophones, but the noise floor is significantly higher than that for the geophones. Cross-well tests using small explosives showed good signal-to-noise ratio in the recorded waveform at various receiver depths with a 1,50-ft source-receiver well separation. For some active downhole surveys, the accelerometer unit would clearly be adequate. It can be reasonably assumed, however, that for less energetic sources and for greater well separations, the high accelerometer noise floor is not acceptable. By expanding the inner working diameter of a microhole seismic tool to 0.5 in., other commercial accelerometers can be used with substantially lower noise floors.« less

  8. Effects of floor location on response of composite fuselage frames

    NASA Technical Reports Server (NTRS)

    Carden, Huey D.; Jones, Lisa E.; Fasanella, Edwin L.

    1992-01-01

    Experimental and analytical results are presented which show the effect of floor placement on the structural response and strength of circular fuselage frames constructed of graphite-epoxy composite material. The research was conducted to study the behavior of conventionally designed advanced composite aircraft components. To achieve desired new designs which incorporate improved energy absorption capabilities requires an understanding of how these conventional designs behave under crash type loadings. Data are presented on the static behavior of the composite structure through photographs of the frame specimen, experimental strain distributions, and through analytical data from composite structural models. An understanding of this behavior can aid the dynamist in predicting the crash behavior of these structures and may assist the designer in achieving improved designs for energy absorption and crash behavior of future structures.

  9. Full-field Deformation Measurement Techniques for a Rotating Composite Shaft

    NASA Technical Reports Server (NTRS)

    Kohlman, Lee W.; Ruggeri, Charles R.; Martin, Richard E.; Roberts, Gary D.; Handschuh, Robert F.; Roth, Don J.

    2012-01-01

    Test methods were developed to view global and local deformation in a composite tube during a test in which the tube is rotating at speeds and torques relevant to rotorcraft shafts. Digital image correlation (DIC) was used to provide quantitative displacement measurements during the tests. High speed cameras were used for the DIC measurements in order to capture images at sufficient frame rates and with sufficient resolution while the tube was rotating at speeds up to 5,000 rpm. Surface displacement data was resolved into cylindrical coordinates in order to measure rigid body rotation and global deformation of the tube. Tests were performed on both undamaged and impact damaged tubes in order to evaluate the capability to detect local deformation near an impact damaged site. Measurement of radial displacement clearly indicated a local buckling deformation near the impacted site in both dynamic and static tests. X-ray computed tomography (CT) was used to investigate variations in fiber architecture within the composite tube and to detect impact damage. No growth in the impact damage area was observed by DIC during dynamic testing or by x-ray CT in post test inspection of the composite tube.

  10. Thermally Conductive Metal-Tube/Carbon-Composite Joints

    NASA Technical Reports Server (NTRS)

    Copeland, Robert J.

    2004-01-01

    An improved method of fabricating joints between metal and carbon-fiber-based composite materials in lightweight radiators and heat sinks has been devised. Carbon-fiber-based composite materials have been used in such heat-transfer devices because they offer a combination of high thermal conductivity and low mass density. Metal tubes are typically used to carry heat-transfer fluids to and from such heat-transfer devices. The present fabrication method helps to ensure that the joints between the metal tubes and the composite-material parts in such heat-transfer devices have both (1) the relatively high thermal conductances needed for efficient transfer of heat and (2) the flexibility needed to accommodate differences among thermal expansions of dissimilar materials in operation over wide temperature ranges. Techniques used previously to join metal tubes with carbon-fiber-based composite parts have included press fitting and bonding with epoxy. Both of these prior techniques have been found to yield joints characterized by relatively high thermal resistances. The present method involves the use of a solder (63 percent Sn, 37 percent Pb) to form a highly thermally conductive joint between a metal tube and a carbon-fiber-based composite structure. Ordinarily, the large differences among the coefficients of thermal expansion of the metal tube, solder, and carbon-fiber-based composite would cause the solder to pull away from the composite upon post-fabrication cooldown from the molten state. In the present method, the structure of the solder is modified (see figure) to enable it to deform readily to accommodate the differential thermal expansion.

  11. Gel spinning of silk tubes for tissue engineering

    PubMed Central

    Lovett, Michael; Cannizzaro, Christopher; Vunjak-Novakovic, Gordana; Kaplan, David L.

    2011-01-01

    Tubular vessels for tissue engineering are typically fabricated using a molding, dipping, or electrospinning technique. While these techniques provide some control over inner and outer diameters of the tube, they lack the ability to align the polymers or fibers of interest throughout the tube. This is an important aspect of biomaterial composite structure and function for mechanical and biological impact of tissue outcomes. We present a novel aqueous process system to spin tubes from biopolymers and proteins such as silk fibroin. Using silk as an example, this method of winding an aqueous solution around a reciprocating rotating mandrel offers substantial improvement in the control of the tube properties, specifically with regard to winding pattern, tube porosity, and composite features. Silk tube properties are further controlled via different post-spinning processing mechanisms such as methanol-treatment, air-drying, and lyophilization. This approach to tubular scaffold manufacture offers numerous tissue engineering applications such as complex composite biomaterial matrices, blood vessel grafts and nerve guides, among others. PMID:18801570

  12. 27 CFR 46.207 - Articles held in bond.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 2 2012-04-01 2011-04-01 true Articles held in bond. 46... Tubes Held for Sale on April 1, 2009 Inventories § 46.207 Articles held in bond. If the dealer is a manufacturer or an export warehouse proprietor and holds articles in TTB bond on April 1, 2009, the floor...

  13. 27 CFR 46.207 - Articles held in bond.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 2 2011-04-01 2011-04-01 false Articles held in bond. 46... Tubes Held for Sale on April 1, 2009 Inventories § 46.207 Articles held in bond. If the dealer is a manufacturer or an export warehouse proprietor and holds articles in TTB bond on April 1, 2009, the floor...

  14. 27 CFR 46.207 - Articles held in bond.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 2 2013-04-01 2013-04-01 false Articles held in bond. 46... Tubes Held for Sale on April 1, 2009 Inventories § 46.207 Articles held in bond. If the dealer is a manufacturer or an export warehouse proprietor and holds articles in TTB bond on April 1, 2009, the floor...

  15. 27 CFR 46.207 - Articles held in bond.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 2 2014-04-01 2014-04-01 false Articles held in bond. 46... Tubes Held for Sale on April 1, 2009 Inventories § 46.207 Articles held in bond. If the dealer is a manufacturer or an export warehouse proprietor and holds articles in TTB bond on April 1, 2009, the floor...

  16. 27 CFR 46.204 - Articles in transit.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 2 2012-04-01 2011-04-01 true Articles in transit. 46.204... Tubes Held for Sale on April 1, 2009 Inventories § 46.204 Articles in transit. The dealer must include articles subject to floor stocks tax that are in transit in the inventory if the dealer holds title to...

  17. 27 CFR 46.207 - Articles held in bond.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 2 2010-04-01 2010-04-01 false Articles held in bond. 46... Tubes Held for Sale on April 1, 2009 Inventories § 46.207 Articles held in bond. If the dealer is a manufacturer or an export warehouse proprietor and holds articles in TTB bond on April 1, 2009, the floor...

  18. Fetal Phthalate Screen: Assessment of Several Phthalate Esters on Fetal Rodent Testosterone Production and Gene Expression Following In Utero Exposure

    EPA Science Inventory

    Phthalate esters(PE) are a large family of compounds used in a wide array of common products from medical tubing to pharmaceuticals to cables, and wall/floor coverings. Laboratory studies have demonstrated that in utero treatment with PE such as di-ethyl hexyl phthalate (DEHP) du...

  19. Advanced bridge safety initiative : investigation of floor beam performance in three steel through-truss bridges - task 7.

    DOT National Transportation Integrated Search

    2014-08-01

    The Advanced Structures and Composites Center at the University of Maine (UMaine) performed live load testing : and rating adjustment factor analysis for three truss bridges. The Maine Department of Transportation (DOT) : indicated that the floor bea...

  20. Evaluation by Rocket Combustor of C/C Composite Cooled Structure Using Metallic Cooling Tubes

    NASA Astrophysics Data System (ADS)

    Takegoshi, Masao; Ono, Fumiei; Ueda, Shuichi; Saito, Toshihito; Hayasaka, Osamu

    In this study, the cooling performance of a C/C composite material structure with metallic cooling tubes fixed by elastic force without chemical bonding was evaluated experimentally using combustion gas in a rocket combustor. The C/C composite chamber was covered by a stainless steel outer shell to maintain its airtightness. Gaseous hydrogen as a fuel and gaseous oxygen as an oxidizer were used for the heating test. The surface of these C/C composites was maintained below 1500 K when the combustion gas temperature was about 2800 K and the heat flux to the combustion chamber wall was about 9 MW/m2. No thermal damage was observed on the stainless steel tubes that were in contact with the C/C composite materials. The results of the heating test showed that such a metallic tube-cooled C/C composite structure is able to control the surface temperature as a cooling structure (also as a heat exchanger) as well as indicated the possibility of reducing the amount of coolant even if the thermal load to the engine is high. Thus, application of this metallic tube-cooled C/C composite structure to reusable engines such as a rocket-ramjet combined-cycle engine is expected.

  1. Performance improvements of the BNC tubes from unique double-silicone-tube bioreactors by introducing chitosan and heparin for application as small-diameter artificial blood vessels.

    PubMed

    Li, Xue; Tang, Jingyu; Bao, Luhan; Chen, Lin; Hong, Feng F

    2017-12-15

    In order to improve property of bacterial nano-cellulose (BNC) to achieve the requirements of clinical application as small caliber vascular grafts, chitosan (CH) was deposited into the fibril network of the BNC tubes fabricated in unique Double-Silicone-Tube bioreactors. Heparin (Hep) was then chemically grafted into the BNC-based tubes using EDC/NHS crosslinking to improve performance of anticoagulation and endothelialization. Physicochemical and mechanical property, blood compatibility, and cytocompatibility were compared before and after compositing. The results indicated that strength at break was increased but burst pressure decreased slightly after compositing. Performance of the BNC tubes was improved remarkably after introducing chitosan and heparin. The EDC/NHS crosslinking catalyzed both amide bonds and ester bonds formation in the BNC/CH-Hep composites. Three-dimensional surface structure and roughness were firstly obtained and discussed in relation to the hemocompatibility of BNC-based tubes. This work demonstrates the heparinized BNC-based tubes have great potential in application as small-diameter vascular prosthesis. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Use of graphite epoxy composites in the Solar-A Soft X-Ray Telescope

    NASA Technical Reports Server (NTRS)

    Jurcevich, B. K.; Bruner, M. E.

    1990-01-01

    This paper describes the use of composite materials in the Soft X-Ray Telescope (SXT). One of the primary structural members of the telescope is a graphite epoxy metering tube. The metering tube maintains the structural stability of the telescope during launch as well as the focal length through various environmental conditions. The graphite epoxy metering tube is designed to have a negative coefficient of thermal expansion to compensate for the positive expansion of titanium structural supports. The focus is maintained to + or - 0.001 inch by matching the CTE of the composite tube to the remaining structural elements.

  3. Basaltic caves at Craters of the Moon National Monument and Preserve as analogs for Mars

    NASA Astrophysics Data System (ADS)

    Hinman, N. W.; Richardson, C. D.; McHenry, L.; Scott, J. R.

    2010-12-01

    Basaltic caves and lava tubes offer stable physicochemical conditions for formation of secondary minerals. Such features, putatively observed on Mars, intercept groundwater to weather country rock, leading to formation of secondary minerals. Further, caves are stable environments to search for evidence of past life, as they could offer protection from the oxidizing martian atmosphere. Searching for signs of life in a cave that could protect bio/organic compounds would preclude the need for risky drilling on Mars. Craters of the Moon National Monument (COM) offers an opportunity to study caves in Holocene iron-rich basalt flows to characterize secondary mineral deposits and search for organic compounds associated with secondary minerals; COM basalts are a good analog for martian basalts because of their high iron but other elements are higher at COM than on Mars. The Blue Dragon flow (~2.1 ka) contains the majority of the accessible caves and lava tubes. Two types of secondary mineral deposits were observed in these caves: ceiling coatings and crack or floor precipitates. Hematite, silica, and calcite comprise ceiling coatings. The crack and floor precipitates are white, efflorescent deposits in cavities along cave walls and ceilings or in localized mounds on cave floors. The secondary minerals in crack and floor precipitates are mainly thenardite and mirabilite with some minor concentrations of trona and/or burkeite. Organic compounds were found associated with the efflorescent deposits. Formation of the deposits is likely due to chemical leaching of basalt by meteoritic water. To test this, fluids collected from the ceiling and walls of the caves were analyzed. Solutions were modeled with the geochemical code, PHREEQC. The model tracked composition as water evaporated. Selected minerals were allowed to precipitate as they became oversaturated. Among the first minerals to become oversaturated were quartz and calcite, which are observed in ceiling deposits. Iron minerals were not included as no iron was detected in solution. Results compared well with evaporation of solutions generated by simulating chemical weathering of minerals found in the basalt; this approach allowed iron minerals to precipitate during evaporation because minerals in the basalt contained iron. The minerals modeled upon evaporation included the minerals observed in the actual deposits - hematite, calcite, and quartz. Na-minerals neared saturation in simulations but were normally not saturated, leaving open the question of their origin. One possible explanation for the presence of Na-minerals could be seasonal ice formation in the caves followed by sublimation, leaving more concentrated solutions behind than were sampled here. A seasonal model for mineral deposition in caves could be relevant to deposits in martian caves. While the formation mechanism for the secondary minerals at COM is not completely understood, the presence of secondary minerals that harbor organic compounds in a cave environment that may be analogous to Mar has implications for where to search for signs of martian life.

  4. Evidence of compositional and ultrastructural shifts during the development of calcareous tubes in the biofouling tubeworm, Hydroides elegans.

    PubMed

    Chan, Vera Bin San; Vinn, Olev; Li, Chaoyi; Lu, Xingwen; Kudryavtsev, Anatoliy B; Schopf, J William; Shih, Kaimin; Zhang, Tong; Thiyagarajan, Vengatesen

    2015-03-01

    The serpulid tubeworm, Hydroides elegans, is an ecologically and economically important species whose biology has been fairly well studied, especially in the context of larval development and settlement on man-made objects (biofouling). Nevertheless, ontogenetic changes associated with calcareous tube composition and structures have not yet been studied. Here, the ultrastructure and composition of the calcareous tubes built by H. elegans was examined in the three early calcifying juvenile stages and in the adult using XRD, FTIR, ICP-OES, SEM and Raman spectroscopy. Ontogenetic shifts in carbonate mineralogy were observed, for example, juvenile tubes contained more amorphous calcium carbonate and were predominantly aragonitic whereas adult tubes were bimineralic with considerably more calcite. The mineral composition gradually shifted during the tube development as shown by a decrease in Sr/Ca and an increase of Mg/Ca ratios with the tubeworm's age. The inner tube layer contained calcite, whereas the outer layer contained aragonite. Similarly, the tube complexity in terms of ultrastructure was associated with development. The sequential appearance of unoriented ultrastructures followed by oriented ultrastructures may reflect the evolutionary history of serpulid tube biominerals. As aragonitic structures are more susceptible to dissolution under ocean acidification (OA) conditions but are more difficult to be removed by anti-fouling treatments, the early developmental stages of the tubeworms may be vulnerable to OA but act as the important target for biofouling control. Copyright © 2015 Elsevier Inc. All rights reserved.

  5. Can pulpal floor debonding be detected from occlusal surface displacement in composite restorations?

    PubMed

    Novaes, João Batista; Talma, Elissa; Las Casas, Estevam Barbosa; Aregawi, Wondwosen; Kolstad, Lauren Wickham; Mantell, Sue; Wang, Yan; Fok, Alex

    2018-01-01

    Polymerization shrinkage of resin composite restorations can cause debonding at the tooth-restoration interface. Theory based on the mechanics of materials predicts that debonding at the pulpal floor would half the shrinkage displacement at the occlusal surface. The aim of this study is to test this theory and to examine the possibility of detecting subsurface resin composite restoration debonding by measuring the superficial shrinkage displacements. A commercial dental resin composite with linear shrinkage strain of 0.8% was used to restore 2 groups of 5 model Class-II cavities (8-mm long, 4-mm wide and 4-mm deep) in aluminum blocks (8-mm thick, 10-mm wide and 14-mm tall). Group I had the restorations bonded to all cavity surfaces, while Group II had the restorations not bonded to the cavity floor to simulate debonding. One of the proximal surfaces of each specimen was sprayed with fine carbon powder to allow surface displacement measurement by Digital Image Correlation. Images of the speckled surface were taken before and after cure for displacement calculation. The experiment was simulated using finite element analysis (FEA) for comparison. Group I showed a maximum occlusal displacement of 34.7±6.7μm and a center of contraction (COC) near the pulpal floor. Group II had a COC coinciding with the geometric center and showed a maximum occlusal displacement of 17.4±3.8μm. The difference between the two groups was statistically significant (p-value=0.0007). Similar results were obtained by FEA. The theoretical shrinkage displacement was 44.6 and 22.3μm for Group I and II, respectively. The lower experimental displacements were probably caused by slumping of the resin composite before cure and deformation of the adhesive layer. The results confirmed that the occlusal shrinkage displacement of a resin composite restoration was reduced significantly by pulpal floor debonding. Recent in vitro studies seem to indicate that this reduction in shrinkage displacement could be detected by using the most accurate intraoral scanners currently available. Thus, subject to clinical validation, the occlusal displacement of a resin composite restoration may be used to assess its interfacial integrity. Copyright © 2017 The Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  6. Application study of filamentary composites in a commercial jet aircraft fuselage

    NASA Technical Reports Server (NTRS)

    Johnson, R. W.; June, R. R.

    1972-01-01

    A study of applications of filamentary composite materials to aircraft fuselage structure was performed. General design criteria were established and material studies conducted using the 727-200 forebody as the primary structural component. Three design approaches to the use of composites were investigated: uniaxial reinforcement of metal structure, uniaxial and biaxial reinforcement of metal structure, and an all-composite design. Materials application studies for all three concepts were conducted on fuselage shell panels, keel beam, floor beams, floor panels, body frames, fail-safe straps, and window frames. Cost benefit studies were conducted and developmental program costs estimated. On the basis of weight savings, cost effectiveness, developmental program costs, and potential for early application on commercial aircraft, the unaxial design is recommended for a 5-year flight service evaluation program.

  7. Calcium, potassium, and sodium content of forest floor arthropods

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Reichle, D.E.; Shanks, M.H.; Crossley, D.A. Jr.

    1969-01-01

    Whole-body nutrient composition of calcium, potassium, and sodium is documented for 37 species of forest floor arthropods. Sodium concentrations averaging 4.6 mg Na/g ash-free dry weight, and potassium concentrations averaging 6.2 mg K/g ash-free dry weight were relatively consistent within and among major taxonomic categories. Calcium content varied from 0.3 to 509.8 mg Ca/g ash-free dry weight, with highest values associated with Diplopoda and related species possessing highly calcified exoskeletons. Within-species variation in chemical composition often exceeded seasonal fluctuations, although several species exhibited significant temporal changes in whole-body nutrient composition of calcium, potassium, and sodium. 9 references, 3 tables.

  8. Design Optimization and Development of Tubular Isogrid Composites Tubes for Lower Limb Prosthesis

    NASA Astrophysics Data System (ADS)

    Junqueira, Diego Morais; Gomes, Guilherme Ferreira; Silveira, Márcio Eduardo; Ancelotti, Antonio Carlos

    2018-04-01

    From the beginnings of humanity, natural or unnatural misfortunes such as illnesses, wars, automobile accidents cause loss of body limbs like teeth, arms, legs, etc. The solution found for the replacement of these missing limbs is in the use of prostheses. Lower limbs tubes or pylons are prosthetics components that are claimed to support loads during walking and other daily tasks activities. Commonly, prosthetic tubes are manufactured using metal materials such as stainless steel, aluminum and titanium. The mass of these tubes is generally high compared to tubes made of carbon fiber reinforced polymer matrix (CFRP) composite. Therefore, this work has the objective of design, manufacturing and analyzing the feasibility of a new tube concept, made of composite material, which makes use of lattice structure and inner layer. Until the present moment, lower limb prosthesis tubes using lattice structure and ineer layer have never been studied and/or tested to date. It can be stated that the tube of rigid ribs with inner layer and angle of 40° is more efficient than those of 26° and 30°. The proposed design allows a structural weight reduction in high performance prostheses from 120 g to 40 g.

  9. Relationship between mechanical-property and energy-absorption trends for composite tubes

    NASA Technical Reports Server (NTRS)

    Farley, Gary L.

    1992-01-01

    U.S. Army helicopters are designed to dissipate prescribed levels of crash impact kinetic energy without compromising the integrity of the fuselage. Because of the complexity of the energy-absorption process it is imperative for designers of energy-absorbing structures to develop an in-depth understanding of how and why composite structures absorb energy. A description of the crushing modes and mechanisms of energy absorption for composite tubes and beams is presented. Three primary crushing modes of composite structures including transverse shearing, lamina bending, and local buckling are described. The experimental data presented show that fiber and matrix mechanical properties and laminate stiffness and strength mechanical properties cannot reliably predict the energy-absorption response of composite tubes.

  10. Energy-absorption capability of composite tubes and beams. Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Farley, Gary L.; Jones, Robert M.

    1989-01-01

    In this study the objective was to develop a method of predicting the energy-absorption capability of composite subfloor beam structures. Before it is possible to develop such an analysis capability, an in-depth understanding of the crushing process of composite materials must be achieved. Many variables affect the crushing process of composite structures, such as the constituent materials' mechanical properties, specimen geometry, and crushing speed. A comprehensive experimental evaluation of tube specimens was conducted to develop insight into how composite structural elements crush and what are the controlling mechanisms. In this study the four characteristic crushing modes, transverse shearing, brittle fracturing, lamina bending, and local buckling were identified and the mechanisms that control the crushing process defined. An in-depth understanding was developed of how material properties affect energy-absorption capability. For example, an increase in fiber and matrix stiffness and failure strain can, depending upon the configuration of the tube, increase energy-absorption capability. An analysis to predict the energy-absorption capability of composite tube specimens was developed and verified. Good agreement between experiment and prediction was obtained.

  11. Indoor air quality and health problems associated with damp floor coverings.

    PubMed

    Tuomainen, Anneli; Seuri, Markku; Sieppi, Anne

    2004-04-01

    To study the relationship between a high incidence of bronchial asthma among employees working in an office building and an indoor air problem related to the degradation of polyvinyl chloride (PVC) floor coverings in the building. The indoor air measurements and results of renovations are also described. Employees' symptoms were surveyed by a questionnaire, and the incidence of asthma was calculated from the medical records for 1997-2000. The quality of indoor air was assessed by microbial sampling and by investigation of the building for possible moisture damage. Indoor air was sampled for volatile organic compounds (VOCs) through Tenax adsorbent tubes. In situ volatile emission measurements from the concrete floor were performed via the field and laboratory emission cell (FLEC) method. In an office with approximately 150 employees, eight new cases of asthma were found in 4 years. In addition, the workers complained of respiratory, conjunctival and nasal symptoms. Emissions indicating the degradation of plastic floor coverings (e.g. 2-ethyl-1-hexanol, 1-butanol) were found in the indoor air and floor material samples. The plastic floor coverings, adhesives and the levelling layers were carefully removed from 12 rooms. The VOCs had diffused into the underlying concrete slabs. The concrete was warmed to remove the diffused VOCs from these areas. After the repairs the concentrations of the VOCs indicating the degradation of PVC, decreased, as did the prevalence of the employees' symptoms and several asthma patients' need for medication. The workers in the office building complained of several respiratory, conjunctival and dermal symptoms. The incidence of adult-onset asthma was approximately nine-times higher than that among Finns employed in similar work. The most probable single cause of the indoor air problem was the degradation of the plastic floor coverings.

  12. Behavior of plywood and fiberglass steel composite tube structures subjected to impact loading

    NASA Astrophysics Data System (ADS)

    Armaghani, Seyamend Bilind

    Paratransit buses are custom built as the major vehicle manufacturer produces the custom built passenger cage installed on the chassis for the Paratransit bus. In order for these Paratransit bus members to be sufficient, they have to be evaluated for crashworthiness and energy absorption. This has prompted Florida Department of Transportation (FDOT) to fund research for the safety evaluation of Paratransit busses consisting of crash and safety analysis. There has been a large body of research done on steel subjected to static loads, but more research is needed for steel applied under dynamic loading and high speeds in order to improve crashworthiness in events such as rollovers and side impacts. Bare steel Hollow Structural Section (HSS) tubing are used a lot as structural members of Paratransit buses because of their lightness and progressive buckling under loading. The research will be conducted on quantifying the tubing's behavior under bending by conducting static three point bending and impact loading tests. In addition to the bare tubing, plywood and fiberglass composites are investigated because they are both strong and lightweight and their behavior under dynamic loading hasn't been quantified. As a result, the main purpose of this research is to quantify the differences between the dynamic and static behavior of plywood steel composite and fiberglass steel composite tubing and compare these findings with those of bare steel tubing. The differences will be quantified using detailed and thorough experiments that will examine the composites behavior under both static and dynamic loading. These tests will determine if there are any advantages of using the composite materials and thus allow for recommendations to be made to the FDOT with the goal of improving the safety of Paratransit busses. Tensile tests were conducted to determine the material properties of the tested specimens. Before the static and dynamic experiments are run to investigate the differences between static and dynamic behavior, Preliminary three point bending testing was conducted to determine the parameters for the final experiments. Static bending testing was conducted on the bare, plywood composite, and fiberglass composite steel tubing. The point of these experiments was to produce a Moment vs. Rotation plot to determine the specimens' maximum moments and their associated rotation, as that is when the steel buckles and fails. The dynamic three point bending experiments were conducted using the impact loading apparatus and had the same purpose as the static experiments. For both static and dynamic experiments, the performances of the different types of specimens were compared based upon their Moment vs. Rotation plots. This will determine the effect that the composite has on the rotation and maximum moment at which the tubing fails. After conducting these experiments, amplification factors were established for each specimen by comparing the maximum moment and their associated rotation between static and dynamic testing. lambda was calculated to quantify the ratio between the static and dynamic maximum moments. beta was used to quantify the ratio between the rotation needed to produce the maximum moment between static and dynamic events. A small amplification factor denotes that material performs well under impact loading and the material doesn't experience dramatic change in behavior during dynamic events. Amplification factors were compared between the bare, plywood, and fiberglass composite steel tubing in order to evaluate the performance of the composites. After comparing the amplification factors of the different types of tubing, recommendations can be made. Fiberglass and plywood composite were shown to be valuable because it decreased the effect of dynamic forces as beta was reduced by a factor of 2 in comparison to bare tubing. Based upon the amplification factors, it was recommended to use 14 gauge fiberglass composite tubing as Paratransit bus structural members because it was affected the least by dynamic loading.

  13. Technique development for modulus, microcracking, hermeticity, and coating evaluation capability characterization of SiC/SiC tubes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hu, Xunxiang; Ang, Caen K.; Singh, Gyanender P.

    Driven by the need to enlarge the safety margins of nuclear fission reactors in accident scenarios, research and development of accident-tolerant fuel has become an important topic in the nuclear engineering and materials community. A continuous-fiber SiC/SiC composite is under consideration as a replacement for traditional zirconium alloy cladding owing to its high-temperature stability, chemical inertness, and exceptional irradiation resistance. An important task is the development of characterization techniques for SiC/SiC cladding, since traditional work using rectangular bars or disks cannot directly provide useful information on the properties of SiC/SiC composite tubes for fuel cladding applications. At Oak Ridge Nationalmore » Laboratory, experimental capabilities are under development to characterize the modulus, microcracking, and hermeticity of as-fabricated, as-irradiated SiC/SiC composite tubes. Resonant ultrasound spectroscopy has been validated as a promising technique to evaluate the elastic properties of SiC/SiC composite tubes and microcracking within the material. A similar technique, impulse excitation, is efficient in determining the basic mechanical properties of SiC bars prepared by chemical vapor deposition; it also has potential for application in studying the mechanical properties of SiC/SiC composite tubes. Complete evaluation of the quality of the developed coatings, a major mitigation strategy against gas permeation and hydrothermal corrosion, requires the deployment of various experimental techniques, such as scratch indentation, tensile pulling-off tests, and scanning electron microscopy. In addition, a comprehensive permeation test station is being established to assess the hermeticity of SiC/SiC composite tubes and to determine the H/D/He permeability of SiC/SiC composites. This report summarizes the current status of the development of these experimental capabilities.« less

  14. Superconductive wire

    DOEpatents

    Korzekwa, David A.; Bingert, John F.; Peterson, Dean E.; Sheinberg, Haskell

    1995-01-01

    A superconductive article is made by inserting a rigid mandrel into an internal cavity of a first metallic tube, said tube having an interior surface and an exterior surface, said interior surface defining the interior cavity, forming a layer of a superconductive material or superconductive precursor upon the exterior surface of said first metallic tube, machining the layer of superconductive material or superconductive precursor to a predetermined diameter to form an intermediate article configured for insertion into a second metallic tube having an interior diameter corresponding to the predetermined diameter, inserting the machined intermediate article into a second metallic tube having an internal diameter corresponding to the predetermined diameter of the intermediate article to form a composite intermediate article, reducing or ironing the composite intermediate article to a predetermined cross-sectional diameter, and sintering the reduced or ironed composite intermediate article at temperatures and for time sufficient for the superconductive material or superconductive precursor to exhibit superconductivity.

  15. Superconductive wire

    DOEpatents

    Korzekwa, D.A.; Bingert, J.F.; Peterson, D.E.; Sheinberg, H.

    1995-07-18

    A superconductive article is made by inserting a rigid mandrel into an internal cavity of a first metallic tube, said tube having an interior surface and an exterior surface, said interior surface defining the interior cavity, forming a layer of a superconductive material or superconductive precursor upon the exterior surface of said first metallic tube, machining the layer of superconductive material or superconductive precursor to a predetermined diameter to form an intermediate article configured for insertion into a second metallic tube having an interior diameter corresponding to the predetermined diameter, inserting the machined intermediate article into a second metallic tube having an internal diameter corresponding to the predetermined diameter of the intermediate article to form a composite intermediate article, reducing or ironing the composite intermediate article to a predetermined cross-sectional diameter, and sintering the reduced or ironed composite intermediate article at temperatures and for time sufficient for the superconductive material or superconductive precursor to exhibit superconductivity. 2 figs.

  16. Method of making a composite tube to metal joint

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Leslie, James C.; Leslie, II, James C.; Heard, James

    A method for making a metal to composite tube joint including selecting an elongated interior fitting constructed with an exterior barrel, reduced in exterior diameter to form a distally facing annular shoulder and then projecting still further distally to form an interior sleeve having a radially outwardly facing bonding surface. Selecting an elongated metal outer sleeve formed proximally with a collar constructed for receipt over the barrel and increased in interior diameter and projecting distally to form an exterior sleeve having a radially inwardly facing bonding surface cooperating with the first bonding surface to form an annulus receiving an extremitymore » of a composite tube and a bond bonding the extremity of the tube to the bonding surfaces.« less

  17. Evaluation of iron aluminide weld overlays for erosion - corrosion resistant boiler tube coatings in low NO{sub x} boilers

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    DuPont, J.N.; Banovic, S.W.; Marder, A.R.

    1996-08-01

    Low NOx burners are being installed in many fossil fired power plants in order to comply with new Clean Air Regulations. Due to the operating characteristics of these burners, boiler tube sulfidation corrosion is often enhanced and premature tube failures can occur. Failures due to oxidation and solid particle erosion are also a concern. A program was initiated in early 1996 to evaluate the use of iron aluminide weld overlays for erosion/corrosion protection of boiler tubes in Low NOx boilers. Composite iron/aluminum wires will be used with the Gas Metal Arc Welding (GMAW) process to prepare overlays on boiler tubesmore » steels with aluminum contents from 8 to 16wt%. The weldability of the composite wires will be evaluated as a function of chemical composition and welding parameters. The effect of overlay composition on corrosion (oxidation and sulfidation) and solid particle erosion will also be evaluated. The laboratory studies will be complemented by field exposures of both iron aluminide weld overlays and co-extruded tubing under actual boiler conditions.« less

  18. A Simple Test to Determine the Effectiveness of Different Braze Compositions for Joining Ti-Tubes to C/C Composite Plates

    NASA Technical Reports Server (NTRS)

    Morscher, Gregory N.; Singh, Mrityunjay; Shpargel, Tarah; Asthana, Rajiv

    2006-01-01

    A simple tube-plate joint tensile test was implemented to compare the effectiveness of commercial brazes, namely, TiCuNi, TiCuSil, and Cu-ABA, used for bonding Ti-tubes joined to C-C composite plates. The different braze systems yielded different; yet, repeatable results. The Cu-ABA system proved to have about twice the load-carrying ability of the other two systems due to the fact that the bonded area between the braze material and the C-C plate was largest for this system. The orientation of the surface fiber tows also had a significant effect on load-carrying ability with tows oriented perpendicular to the tube axis displaying the highest failure loads. Increasing the process load and modifying the surface of the C-C plate by grooving out channels for the Ti-Tube to nest in resulted in increased load-carrying ability for the TiCuSil and Cu-ABA systems due to increased bonded area and better penetration of the braze material into the C-C composite.

  19. Inspecting the inside of underwater hull

    NASA Astrophysics Data System (ADS)

    Valkovic, Vladivoj; Sudac, Davorin

    2009-05-01

    In order to demonstrate the possibility of identifying the material within ship's underwater hull, sunken ships and other objects on the sea floor tests with the 14 MeV sealed tube neutron generator incorporated inside a small submarine submerged in the test basin filled with sea water have been performed. Results obtained for inspection of diesel fuel and explosive presence behind single and double hull constructions are presented.

  20. Statistical Energy Analysis (SEA) and Energy Finite Element Analysis (EFEA) Predictions for a Floor-Equipped Composite Cylinder

    NASA Technical Reports Server (NTRS)

    Grosveld, Ferdinand W.; Schiller, Noah H.; Cabell, Randolph H.

    2011-01-01

    Comet Enflow is a commercially available, high frequency vibroacoustic analysis software founded on Energy Finite Element Analysis (EFEA) and Energy Boundary Element Analysis (EBEA). Energy Finite Element Analysis (EFEA) was validated on a floor-equipped composite cylinder by comparing EFEA vibroacoustic response predictions with Statistical Energy Analysis (SEA) and experimental results. Statistical Energy Analysis (SEA) predictions were made using the commercial software program VA One 2009 from ESI Group. The frequency region of interest for this study covers the one-third octave bands with center frequencies from 100 Hz to 4000 Hz.

  1. Tensile Response of Hoop Reinforced Multiaxially Braided Thin Wall Composite Tubes

    NASA Astrophysics Data System (ADS)

    Roy, Sree Shankhachur; Potluri, Prasad; Soutis, Constantinos

    2017-04-01

    This paper presents the tensile response of thin-walled composite tubes with multi-axial fibre architecture. A hybrid braid-wound layup has the potential to optimise the composite tube properties, however, stacking sequence plays a role in the failure mechanism. A braid-winding method has been used to produce stacked overwound braid layup [(±45°/0°)5/90°4]T. Influence of stacking sequence on premature failure of hoop layers has been reported. Under tensile loading, a cross-ply composite tube with the alternate stacking of hoop and axial fibre show hoop plies splitting similar to the overwound braided composite tube. However, splitting has been restricted by the surrounding axial plies and contained between the adjacent axial fibre tows. This observation suggests hoop layers sandwiched between braid layers will improve structural integrity. A near net shape architecture with three fibre orientation in a triaxial braid will provide additional support to prevent extensive damage for plies loaded in off-axis. Several notable observations for relatively open braid structures such as tow scissoring, high Poisson's ratio and influence of axial tow crimp on the strain to failure have been reported. Digital Image Correlation (DIC) in conjunction with surface strain gauging has been employed to capture the strain pattern.

  2. Complex Volcanism at Oppenheimer U Floor-Fractured Crater

    NASA Technical Reports Server (NTRS)

    Gaddis, L. R.; Bennett, K.; Horgan, B.; McBride, Marie; Stopar, J.; Lawrence, S.; Gustafson, J. O.; Giguere, T.

    2017-01-01

    Recent remote sensing studies have identified complex volcanism in the floor-fractured crater (FFC) Oppenheimer U, located in the northwest floor of Oppenheimer crater (35.2degS, 166.3degW, 208 km dia., Figure 1) within the "South Pole - Aitken basin" (SPA) region of the lunar far side. Up to 15 sites of pyroclastic volcanism have been identified in the floor of Oppenheimer crater. Studies of Moon Mineralogy Mapper data (M3, 0.4-3 microns, 86 bands, [5]) indicated that the pyroclastic deposits are comprised of mixtures of clinopyroxene and iron-rich glass, with the Oppenheimer U deposit showing variable composition within the FFC and having the most iron-rich volcanic glass thus far identified on the Moon. Here we examine the floor of Oppenheimer U in more detail and show evidence for possible multiple eruptive vents.

  3. Strong, corrosion-resistant aluminum tubing

    NASA Technical Reports Server (NTRS)

    Reed, M. W.; Adams, F. F.

    1980-01-01

    When aluminum tubing having good corrosion resistance and postweld strength is needed, type 5083 alloy should be considered. Chemical composition is carefully controlled and can be drawn into thin-wall tubing with excellent mechanical properties. Uses of tubing are in aircraft, boats, docks, and process equipment.

  4. Active Metal Brazing and Characterization of Brazed Joints in Titanium to Carbon-Carbon Composites

    NASA Technical Reports Server (NTRS)

    Singh, M.; Shpargel, T. P.; Morscher, G. N.; Asthana, R.

    2006-01-01

    The Ti-metal/C-C composite joints were formed by reactive brazing with three commercial brazes, namely, Cu-ABA, TiCuNi, and TiCuSiI. The joint microstructures were examined using optical microscopy and scanning electron microscopy (SEM) coupled with energy dispersive spectrometry (EDS). The results of the microstructure analysis indicate solute redistribution across the joint and possible metallurgical bond formation via interdiffusion, which led to good wetting and spreading. A tube-on-plate tensile test was used to evaluate joint strength of Ti-tube/ C-C composite joints. The load-carrying ability was greatest for the Cu-ABA braze joint structures. This system appeared to have the best braze spreading which resulted in a larger braze/C-C composite bonded area compared to the other two braze materials. Also, joint loadcarrying ability was found to be higher for joint structures where the fiber tows in the outer ply of the C-C composite were aligned perpendicular to the tube axis when compared to the case where fiber tows were aligned parallel to the tube axis.

  5. Separation phenomena for gaseous mixture flowing through a long tube into vacuum

    NASA Astrophysics Data System (ADS)

    Sharipov, Felix; Kalempa, Denize

    2005-12-01

    A gaseous mixture flow through a long tube into vacuum is considered assuming the pressure to be arbitrary at the tube entrance. Thus, the flow regime can vary from hydrodynamic at the entrance to free molecular at the tube exit. The distributions of density and concentration along the tube were obtained for the mixture helium-xenon at various values of the concentration and rarefaction at the tube entrance. It was shown that the variation of the concentration along the tube can be significant. The flow rates of both species determining the chemical composition in the down flow container were calculated. An analysis of these data shows that the chemical composition in the down flow container can be different from that in the up flow one, i.e., the separation phenomenon takes place. The results presented in the article can be used in practice to avoid the separation phenomenon or to intensify it if necessary.

  6. Experimental investigations on steel-concrete composite columns for varying parameters

    NASA Astrophysics Data System (ADS)

    Aparna, V.; Vivek, D.; Neelima, Kancharla; Karthikeyan, B.

    2017-07-01

    In this study, the experimental investigations on steel tubes filled with different types of concrete are presented. Steel tubes filled with fibre reinforced concrete using lathe waste and steel tube with concerned confined with steel mesh were investigated. The combinations were compared with steel tubes with conventional concrete. A total of 4 concrete filled steel tube (CFST) combinations were made with tubes of diameter 100 mm with wall thickness 1.6 mm and a height of 300 mm. Axial compression test to examine the resisting capacity of the columns and push-out test for noting the bond strength were performed. Coupon tests were also conducted to determine the mechanical properties of steel. The structural behaviour of the composite columns was evaluated from on the test results. It was observed that steel tube filled fibre reinforced possessed better bond strength and resistance to axial load.

  7. Characterization of Reinforced Structural Composites with Carbon Nanotubes Grown Directly on the Fibers/Fabrics Using the PopTube Approach

    NASA Astrophysics Data System (ADS)

    Guin, William Edward

    Carbon nanotubes (CNTs) are ideal candidates for the reinforcement of the matrix and interphase zone in polymer matrix composites (PMCs), due to their ability to more effectively bind the reinforcing fibers to the matrix material. This can lead to the enhancement of several critical composite properties - including interfacial shear strength and interlaminar fracture toughness - that are typically associated with a composite material's resistance to delamination. Direct dispersion of CNTs into the matrix of the composites has been shown to be very difficult. A more effective way to reinforce PMCs using CNTs is to grow CNTs directly on the reinforcing fibers. To this end, a novel technique used to grow CNTs directly on carbon fibers has been developed at The University of Alabama and Auburn University. This method, referred to as the PopTube Approach, uses microwave irradiation to grow CNTs at room temperature in air, without the need for inert gas protection or additional feed stock gases. The simple nature of the PopTube Approach lends itself to large-scale, high-yield manufacturing that can be done in a cost effective manner. However, before this technique is developed beyond the laboratory scale, its effectiveness as a route to produce CNT-reinforced composites must be evaluated in a comprehensive manner. The objective of this work is to do just that - characterize the mechanical properties of CNT-reinforced composites produced via the PopTube Approach. A systematic experimental program is carried out to provide a comprehensive assessment of the effects of the PopTube Approach on a wide range of composite mechanical properties. Results show that the PopTube Approach provides for enhanced resistance to delamination with respect to several different loading events. Fractography studies are used to qualitatively understand the mechanisms responsible for these improvements in delamination resistance on the micro-scale. Results also suggest that improvements in delamination resistance via CNT reinforcement may come at the expense of the tensile properties of PMCs - which gives rise to the conclusion that in practice, the degree and manner of CNT reinforcement in PMCs should be carefully considered on an application-by-application basis. Together, the collection of studies performed herein provides a wide-ranging quantitative and qualitative assessment of the effects of the PopTube Approach CNT reinforcement scheme on the mechanical properties and behavior of polymer matrix composites.

  8. Surficial geology of the sea floor in Central Rhode Island Sound Southeast of Point Judith, Rhode Island

    USGS Publications Warehouse

    McMullen, K.Y.; Poppe, L.J.; Ackerman, S.D.; Blackwood, D.S.; Schaer, J.D.; Nadeau, M.A.; Wood, D.A.

    2011-01-01

    The U.S. Geological Survey (USGS) and the National Oceanic and Atmospheric Administration (NOAA) are working together to study sea-floor environments off the northeast coast of the United States. During 2008, NOAA survey H11996 collected multibeam echosounder data in a 65-square kilometer area in central Rhode Island Sound, southeast of Point Judith, Rhode Island. During 2010, the USGS collected bottom photographs and sediment samples from 25 stations in this study area. The bathymetry, photography, and sediment data are used to interpret sea-floor features including scour depressions, sand waves, trawl marks, and dredge spoils. Scour depressions cover the bathymetric highs in much of the study area. Sand waves are located mostly in the southwest, and trawl marks tend to be in the northern regions. Dredge spoils are located at a disposal site in a bathymetric low in the western end of the study area. Most stations have a sea-floor surface of sand or silty sand, but eight of the stations have boulders to pea-sized gravel or gravelly sediment on the surface. Photographs show sandy areas typically have scattered burrows, shells, amphipod communities, and worm tubes. Boulders and cobbles are commonly overgrown with hydrozoans and anemones.

  9. Center for Composites Manufacturing : fabrication guide

    DOT National Transportation Integrated Search

    2003-06-01

    The objective of this report is to describe thermoplastic composite materials and processes and to demonstrate fabrication methods for molding these materials into transit bus flooring components or other large components for use in buses and other m...

  10. Usefulness of the anterolateral thigh flap with vascularized fascia lata for reconstruction of orbital floor and nasal surface after total maxillectomy.

    PubMed

    Joo, Young-Hoon; Cho, Kwang-Jae; Park, Jun-Ook; Kim, Min-Sik

    2013-09-01

    The aim of this study was to describe a technique using the fascia lata (FL) component of the anterolateral thigh (ALT) flap to re-create the orbital floor and lateral nasal wall after total maxillectomy. Retrospective analysis of medical records. A total of 22 patients underwent maxillary reconstruction using a composite ALT-FL flap following cancer resection. All patients underwent total maxillectomies via the Weber-Ferguson approach. The ALT flap was harvested with the deep fascia of the thigh with the aim of using it for lining of the orbital floor and lateral nasal cavity. The FL was sutured to the palatine bone inferiorly, nasal bone and zygomatic bone superiorly, and nasopharyngeal mucosa posteriorly to provide an orbital floor and make a neonasal cavity. There was 100% free flap survival. Speech was normal in eight (36%) patients, near normal in 10 (46%), and intelligible in four (18%). Seventeen (77%) patients gained a good facial appearance, and five (23%) a fair appearance. Sixteen (73%) patients complained of mild nasal crust formation, and the rest (27%) developed moderate crust. Microvascular reconstruction using a composite ALT-FL flap provided a reliable fascial component for orbital floor and nasal surface reconstruction of total maxillectomy defects. Copyright © 2013 The American Laryngological, Rhinological and Otological Society, Inc.

  11. Application of sandwich honeycomb carbon/glass fiber-honeycomb composite in the floor component of electric car

    NASA Astrophysics Data System (ADS)

    Sukmaji, I. C.; Wijang, W. R.; Andri, S.; Bambang, K.; Teguh, T.

    2017-01-01

    Nowadays composite is a superior material used in automotive component due to its outstanding mechanical behavior. The sandwich polypropylene honeycomb core with carbon/glass fiber composite skin (SHCG) as based material in a floor component of electric car application is investigated in the present research. In sandwich structure form, it can absorb noise better compare with the conventional material [1]. Also in present paper, Finite Element Analysis (FEA) of SHCG as based material for floor component of the electric car is analyzed. The composite sandwich is contained with a layer uniform carbon fiber and mixing non-uniform carbon-glass fiber in upper and lower skin. Between skins of SHCG are core polypropylene honeycomb that it have good flexibility to form following dies profile. The variables of volume fraction ratio of carbon/glass fiber in SHCG skin are 20/80%, 30/70%, and 50/50%. The specimen of SHCG is tested using the universal testing machine by three points bending method refers to ASTM C393 and ASTM C365. The cross point between tensile strength to the volume fraction the mixing carbon/glass line and ratio cost line are the searched material with good mechanical performance and reasonable cost. The point is 30/70 volume fraction of carbon/glass fiber. The result of the testing experiment is become input properties of model structure sandwich in FEA simulation. FEA simulation approach is conducted to find critical strength and factor of complex safety geometry against varied distributed passenger loads of a floor component the electric car. The passenger loads variable are 80, 100, 150, 200, 250 and 300 kg.

  12. Comparative evaluation of microleakage in Class II restorations using open vs. closed centripetal build-up techniques with different lining materials

    PubMed Central

    Sawani, Shefali; Arora, Vipin; Jaiswal, Shikha; Nikhil, Vineeta

    2014-01-01

    Background: Evaluation of microleakage is important for assessing the success of new restorative materials and methods. Aim and Objectives: Comparative evaluation of microleakage in Class II restorations using open vs. closed centripetal build-up techniques with different lining materials. Materials and Methods: Standardized mesi-occlusal (MO) and distoocclusal (DO) Class II tooth preparations were preparedon 53 molars and samples were randomly divided into six experimental groups and one control group for restorations. Group 1: Open-Sandwich technique (OST) with flowable composite at the gingival seat. Group 2: OST with resin-modified glass ionomer cement (RMGIC) at the gingival seat. Group 3: Closed-Sandwich technique (CST) with flowable composite at the pulpal floor and axial wall. Group 4: CST with RMGIC at the pulpal floor and axial wall. Group 5: OST with flowable composite at the pulpal floor, axial wall, and gingival seat. Group 6: OST with RMGIC at the pulpal floor, axial wall, and gingival seat. Group 7: Control — no lining material, centripetal technique only. After restorations and thermocycling, apices were sealed and samples were immersed in 0.5% basic fuchsin dye. Sectioning was followed by stereomicroscopic evaluation. Results: Results were analyzed using Post Hoc Bonferroni test (statistics is not a form of tabulation). Cervical scores of control were more than the exprimental groups (P < 0.05). Less microleakage was observed in CST than OST in all experimental groups (P < 0.05). However, insignificant differences were observed among occlusal scores of different groups (P > 0.05). Conclusion: Class II composite restorations with centripetal build-up alone or when placed with CST reduces the cervical microleakage when compared to OST. PMID:25125847

  13. Boreal earliest Triassic biotas elucidate globally depauperate hard substrate communities after the end-Permian mass extinction.

    PubMed

    Zatoń, Michał; Niedźwiedzki, Grzegorz; Blom, Henning; Kear, Benjamin P

    2016-11-08

    The end-Permian mass extinction constituted the most devastating biotic crisis of the Phanerozoic. Its aftermath was characterized by harsh marine conditions incorporating volcanically induced oceanic warming, widespread anoxia and acidification. Bio-productivity accordingly experienced marked fluctuations. In particular, low palaeolatitude hard substrate communities from shallow seas fringing Western Pangaea and the Tethyan Realm were extremely impoverished, being dominated by monogeneric colonies of filter-feeding microconchid tubeworms. Here we present the first equivalent field data for Boreal hard substrate assemblages from the earliest Triassic (Induan) of East Greenland. This region bordered a discrete bio-realm situated at mid-high palaeolatitude (>30°N). Nevertheless, hard substrate biotas were compositionally identical to those from elsewhere, with microconchids encrusting Claraia bivalves and algal buildups on the sea floor. Biostratigraphical correlation further shows that Boreal microconchids underwent progressive tube modification and unique taxic diversification concordant with changing habitats over time. We interpret this as a post-extinction recovery and adaptive radiation sequence that mirrored coeval subequatorial faunas, and thus confirms hard substrate ecosystem depletion as a hallmark of the earliest Triassic interval globally.

  14. Boreal earliest Triassic biotas elucidate globally depauperate hard substrate communities after the end-Permian mass extinction

    NASA Astrophysics Data System (ADS)

    Zatoń, Michał; Niedźwiedzki, Grzegorz; Blom, Henning; Kear, Benjamin P.

    2016-11-01

    The end-Permian mass extinction constituted the most devastating biotic crisis of the Phanerozoic. Its aftermath was characterized by harsh marine conditions incorporating volcanically induced oceanic warming, widespread anoxia and acidification. Bio-productivity accordingly experienced marked fluctuations. In particular, low palaeolatitude hard substrate communities from shallow seas fringing Western Pangaea and the Tethyan Realm were extremely impoverished, being dominated by monogeneric colonies of filter-feeding microconchid tubeworms. Here we present the first equivalent field data for Boreal hard substrate assemblages from the earliest Triassic (Induan) of East Greenland. This region bordered a discrete bio-realm situated at mid-high palaeolatitude (>30°N). Nevertheless, hard substrate biotas were compositionally identical to those from elsewhere, with microconchids encrusting Claraia bivalves and algal buildups on the sea floor. Biostratigraphical correlation further shows that Boreal microconchids underwent progressive tube modification and unique taxic diversification concordant with changing habitats over time. We interpret this as a post-extinction recovery and adaptive radiation sequence that mirrored coeval subequatorial faunas, and thus confirms hard substrate ecosystem depletion as a hallmark of the earliest Triassic interval globally.

  15. Cryogenic-Compatible Winchester Connector Mount and Retaining System for Composite Tubes

    NASA Technical Reports Server (NTRS)

    Pontius, James; McGuffey, Douglas

    2011-01-01

    A connector retainer and mounting system has been designed to replace screw-mounting of Winchester connectors. Countersunk screws are normally used to secure connectors to structures, and to keep them from coming apart. These screws are normally put into threaded or through-holes in metallic structures. This unique retainer is designed such that integral posts keep the connector halves retained, and a groove permits a cable tie to be fastened around the retainer and composite tube, thus securing the connector to the structure. The system is compatible for use on cryogenic (and conventional) bonded composite tube assemblies. Screws and tapped/through-holes needed to retain and mount Winchester connectors cannot be used on blind-access composite tubes. This system allows for rapid installation, removal, low-molecular-outgassing materials, and particulate-free installation and removal. Installation and/or changes late in the integration, and test flow with limited access in a cleanroom environment are possible. No sanding or bonding is needed.

  16. Innovative energy absorbing devices based on composite tubes

    NASA Astrophysics Data System (ADS)

    Tiwari, Chandrashekhar

    Analytical and experimental study of innovative load limiting and energy absorbing devices are presented here. The devices are based on composite tubes and can be categorized in to two groups based upon the energy absorbing mechanisms exhibited by them, namely: foam crushing and foam fracturing. The device based on foam crushing as the energy absorbing mechanism is composed of light weight elastic-plastic foam filling inside an angle ply composite tube. The tube is tailored to have a high Poisson’s ratio (>20). Upon being loaded the device experiences large transverse contraction resulting in rapid decrease in diameter. At a certain axial load the foam core begins to crush and energy is dissipated. This device is termed as crush tube device. The device based upon foam shear fracture as the energy absorbing mechanism involves an elastic-plastic core foam in annulus of two concentric extension-twist coupled composite tubes with opposite angles of fibers. The core foam is bonded to the inner and outer tube walls. Upon being loaded axially, the tubes twist in opposite directions and fracture the core foam in out of plane shear and thus dissipate the energy stored. The device is termed as sandwich core device (SCD). The devices exhibit variations in force-displacement characteristics with changes in design and material parameters, resulting in wide range of energy absorption capabilities. A flexible matrix composite system was selected, which was composed of high stiffness carbon fibers as reinforcements in relatively low stiffness polyurethane matrix, based upon large strain to failure capabilities and large beneficial elastic couplings. Linear and non-linear analytical models were developed encapsulating large deformation theory of the laminated composite shells (using non-linear strain energy formulation) to the fracture mechanics of core foam and elastic-plastic deformation theory of the foam filling. The non-linear model is capable of including material and geometric nonlinearities that arise from large deformation and fiber reorientation. Developed non-linear analysis predicts the behavior of extension-twist coupled and angle ply flexible matrix composite tubes under multi-axial loadings. The predicted results show close correlation with experimental findings. It was also found that these devices exhibit variations with respect to rate of loading. It was found that the novel energy absorbing devices are capable of providing 4-5 times higher specific energy absorption (SEA) than currently used devices for similar purposes (such as wire bender which has SEA of 3.6 J/g).

  17. Abundance and distribution of vegetation under four hardwood stands in north-central West Virginia

    Treesearch

    G.W. Wendel; G.W. Wendel

    1987-01-01

    Forest floor samples were collected from four hardwood forest stands in West Virginia to study species composition, abundance, and distribution of vegetation that originated from seeds, rootstocks, rhizomes, and so on. The abundance and distribution of plants on square-foot sections of forest floor that were lifted and moved to the greenhouse indicate that under the...

  18. Finite Element Analysis of Tunable Composite Tubes Reinforced with Auxetic Structures

    PubMed Central

    2017-01-01

    A tubular composite structure that is built of two materials, characterized by different Young moduli, is analysed in this paper. The Young’s modulus of one of these materials can be controlled by external conditions e.g., magnetic or electric field, temperature etc. The geometry of the reinforcement is based on typical auxetic re-entrant honeycomb cellular structure. The influence of this external factor on the behaviour of the stretched tube is analysed in this paper. Also, the possibility of creating a tubular composite structure whose cross-section is either shrinking or expanding, while stretching the tube is presented. PMID:29186882

  19. Effect of species composition on carbon and nitrogen stocks in forest floor and mineral soil in Norway spruce and European beech mixed forests

    NASA Astrophysics Data System (ADS)

    Andivia, Enrique; Rolo, Víctor; Jonard, Mathieu; Formánek, Pavel; Ponette, Quentin

    2015-04-01

    Management of existing forests has been identified as the main strategy to enhance carbon sequestration and to mitigate the impact of climate change on forest ecosystems. In this direction, the conversion of Norway spruce monospecific stands into mixed stands by intermingling individuals of European beech is an ongoing trend in adaptive forest management strategies, especially in Central Europe. However, studies assessing the effect of changes in tree species composition on soil organic carbon (SOC) and nitrogen stocks are still scarce and there is a lack of scientific evidence supporting tree species selection as a feasible management option to mitigate the effects of predicted future climatic scenarios. We compared C and N stocks in the forest floor (litter and humus) and the top 10 cm of mineral soil in two monospecific stands of Norway spruce and European beech and in a mixed stand of both species. The effect of tree species composition on the C and N stocks and its spatial distribution was evaluated based on litterfall, root production, elevation and canopy opening, and by using a combination of modelling and geostatistical techniques. C stock was highest in the Norway spruce and the mixed stands, while N stock was highest in the mixed stand and lowest under European beech, with intermediate values in the Norway spruce stand. Each forest type showed differences in forest floor properties, suggesting that species composition is an important factor governing forest floor characteristics, including C and N stocks. The distribution of C and N stocks between forest soil layers was different for each forest type. C and N stocks were highest in the hummus layer under Norway spruce, whereas both stocks were lowest in the European beech stand. On the other hand, the mixed stand showed the highest C and N accumulation in the uppermost mineral soil layer, while the monospecific stands showed similar values. Litterfall was the main contribution to C and N stocks of the humus layer in monospecific stands. Forest floor stocks were also influenced by microelevation and canopy opening in the European beech stand and by microelevation in the Norway spruce stand. Root turnover and Norway spruce litterfall proportion directly increased C stocks in the mineral soil of the mixed stand. Additionally, N stock in the forest floor of the mixed stand was positively correlated with the Norway spruce litterfall proportion. Spatial analyses further confirmed that species composition was the main source of spatial variability of SOC stock in mixed stands. These results suggest that the admixture of individuals of European beech and Norway spruce may lead to a translocation of SOC from the forest floor to the better protected mineral soil layer, which might be beneficial for long term SOC sequestration.

  20. Type of litter determines the formation and properties of charred material during wildfires

    NASA Astrophysics Data System (ADS)

    Chavez, Bruno; Fonturbel, M. Teresa; Salgado, Josefa; García-Oliva, Felipe; Vega, Jose A.; Merino, Agustin

    2014-05-01

    Wildfire is one of the most important disturbances all over the World, affecting both the amount and composition of forest floor and mineral soils. In comparison with unburnt areas, wildfire-affected forest floor usually shows lower contents of labile C compounds and higher concentrations of recalcitrant aromatic forms. These changes in composition can have important impact on biogeochemical cycles and therefore ecosystem functions. Although burning of different types of litter can lead to different amount and types of pyrogenic compounds, this aspect has not been evaluated yet. The effect of wildfire on SOM composition and stability were evaluated in five major types of non-wood litter in Mediterranean ecosystems: Pinus nigra, E. arborea, P. pinaster, U. europaeus and Eucalyptus globulus. In each of these ecosystems, forest floor samples from different soil burn severities were sampled. Soil burnt severities were based on visual signs of changes in forest floor and deposition of ash. Pyrogenic carbon quality were analysed using elementary analysis, solid-state 13 C nuclear magnetic resonance spectroscopy, Reflectance Infrared Fourier Transform (FTIR) and thermal analysis (simultaneous DSC-TG). The study showed that the different types of litter influenced the formation and characteristics of charred material. They differed in the temperature at which they start to be formed, the amounts of charred compounds and in their chemical composition. The resulting charred materials from the different litter, showed an important variability in the degree of carbonitation/aromatization. Unlike the biochar obtained through pyrolysis of woody sources, which contains exclusively aromatic structures, in the charred material produced in some litter, lignin, cellulose and even cellulose persist even in the high soil burnt severity. Coinciding with increases in aromatic contents, important decreases in atomic H/C and O/C ratios were recorded. However, the values found in some litters, were higher than 0.5, suggesting that low degree of carbonization/aromatization. Although burning also led to compounds of higher thermal recalcitrance (increases in T50 values), values recorded in some litters were lower than those measured in highly polycondensed aromatic compounds. The differences found among the different forest floor cannot be only attributable to the initial SOM composition of the litter. Other aspects, such as the different thermal sensitivity, flammability and different conditions during wildfire (temperatures, combustion duration, oxygen concentrations) could also have contributed.

  1. Strength of SiCf-SiCm composite tube under uniaxial and multiaxial loading

    NASA Astrophysics Data System (ADS)

    Shapovalov, Kirill; Jacobsen, George M.; Alva, Luis; Truesdale, Nathaniel; Deck, Christian P.; Huang, Xinyu

    2018-03-01

    The authors report mechanical strength of nuclear grade silicon carbide fiber reinforced silicon carbide matrix composite (SiCf-SiCm) tubing under several different stress states. The composite tubing was fabricated via a Chemical Vapor Infiltration (CVI) process, and is being evaluated for accident tolerant nuclear fuel cladding. Several experimental techniques were applied including uniaxial tension, elastomer insert burst test, open and closed end hydraulic bladder burst test, and torsion test. These tests provided critical stress and strain values at proportional limit and at ultimate failure points. Full field strain measurements using digital image correlation (DIC) were obtained in order to acquire quantitative information on localized deformation during application of stress. Based on the test results, a failure map was constructed for the SiCf-SiCm composites.

  2. Nuclear fuel element

    DOEpatents

    Armijo, Joseph S.; Coffin, Jr., Louis F.

    1980-04-29

    A nuclear fuel element for use in the core of a nuclear reactor is disclosed and has an improved composite cladding comprised of a moderate purity metal barrier of zirconium metallurgically bonded on the inside surface of a zirconium alloy tube. The metal barrier forms a shield between the alloy tube and a core of nuclear fuel material enclosed in the composite cladding. There is a gap between the cladding and the core. The metal barrier forms about 1 to about 30 percent of the thickness of the composite cladding and has low neutron absorption characteristics. The metal barrier serves as a preferential reaction site for gaseous impurities and fission products and protects the alloy tube from contact and reaction with such impurities and fission products. Methods of manufacturing the composite cladding are also disclosed.

  3. Electromagnetic Monitoring of Lava Tubes: Numerical Modeling and Instrument Testing

    NASA Astrophysics Data System (ADS)

    Sly, Michael K.

    Currently the only method to measure the flow rates of lava in lava tubes is through the use of a skylight. This means that only a fraction of lava tubes can be measured. It is important to know the flow rate throughout a lava tube to know how much lava is being produced by a volcano at a given time. In order to measure the flow rate without using a skylight we can utilize the electromagnetic properties of flowing lava and the Lorentz force. Theoretical as well as numerical methods have been used to model an expected response using this technique. The experimental results will be compared to these models to discern accuracy. The main difficulty involved in this experiment is the high resistivity of the basalt that surrounds the lava tube. In order to obtain measurements in this environment high impedance electrodes are needed. After months of development and testing, multiple high impedance electrodes are available to be used on any surface including basalt. These electrodes are able to measure electric signals through any highly resistive surface including concrete, asphalt, basalt, and ice. Currently no tests have been done or are planned to measure flowing lava. Instead we will measure flowing sea water in pipes on the SIO campus. These pipes provide a good analog to the lava tubes. These tests have provided useful information about the noise floor for this system, telling us that a response from a full size lava tube could most likely be seen.

  4. Evaluation of capillary reinforced composites

    NASA Technical Reports Server (NTRS)

    Cahill, J. E.; Halase, J. F.; South, W. K.; Stoffer, L. J.

    1985-01-01

    Anti-icing of the inlet of jet engines is generally performed with high pressure heated air that is directed forward from the compressor through a series of pipes to various manifolds located near the structures to be anti-iced. From these manifolds, the air is directed to all flowpath surfaces that may be susceptible to ice formation. There the anti-icing function may be performed by either heat conduction or film heating. Unfortunately, the prospect of utilizing lighweight, high strength composites for inlet structures of jet engines has been frustrated by the low transverse thermal conductivity of such materials. It was the objective of this program to develop an advanced materials and design concept for anti-icing composite structures. The concept that was evaluated used capillary glass tubes embedded on the surface of a composite structure with heated air ducted through the tubes. An analytical computer program was developed to predict the anti-icing performance of such tubes and a test program was conducted to demonstrate actual performance of this system. Test data and analytical code results were in excellent agreement. Both indicate feasibility of using capillary tubes for surface heating as a means for composite engine structures to combat ice accumulation.

  5. Modelling the side impact of carbon fibre tubes

    NASA Astrophysics Data System (ADS)

    Sudharsan, Ms R.; Rolfe, B. F., Dr; Hodgson, P. D., Prof

    2010-06-01

    Metallic tubes have been extensively studied for their crashworthiness as they closely resemble automotive crash rails. Recently, the demand to improve fuel economy and reduce vehicle emissions has led automobile manufacturers to explore the crash properties of light weight materials such as fibre reinforced polymer composites, metallic foams and sandwich structures in order to use them as crash barriers. This paper discusses the response of carbon fibre reinforced polymer (CFRP) tubes and their failure mechanisms during side impact. The energy absorption of CFRP tubes is compared to similar Aluminium tubes. The response of the CFRP tubes during impact was modelled using Abaqus finite element software with a composite fabric material model. The material inputs were given based on standard tension and compression test results and the in-plane damage was defined based on cyclic shear tests. The failure modes and energy absorption observed during the tests were well represented by the finite element model.

  6. Investigating the fall-injury reducing effect of impact absorbing flooring among female nursing home residents: initial results.

    PubMed

    Gustavsson, Johanna; Bonander, Carl; Andersson, Ragnar; Nilson, Finn

    2015-10-01

    Fall-related injuries affect the lives of elderly to a substantial degree. This quasi-experimental study investigates the fall-injury reducing effect of impact absorbing flooring among female nursing home residents. The intervention site is a nursing home in Sweden where impact absorbing flooring was installed in parts of one of six wards (six out of 10 apartments (excluding bathrooms), the communal dining-room and parts of the corridor). The impact absorbing flooring is a 12 mm thick closed cell flexible polyurethane/polyurea composite tile (500×500 mm) with an exterior surface of polyurethane/polyurea. A generalised linear model (log-binomial) was used to calculate the RR of injury from falls on impact absorbing flooring compared to falls on regular flooring, adjusted for age, body mass index, visual and cognitive impairments. During the study period (1 October 2011 to 31 March 2014), 254 falls occurred on regular flooring and 77 falls on impact absorbing flooring. The injury/fall rate was 30.3% for falls on regular flooring and 16.9% for falls on impact absorbing flooring. Adjusted for covariates, the impact absorbing flooring significantly reduced the RR of injury in the event of a fall by 59% (RR 0.41 (95% Cl 0.20 to 0.80)). This is, to our knowledge, the first study evaluating the injury-reducing effect of impact absorbing flooring in a nursing home showing statistically significant effect. The results from this study are promising, indicating the considerable potential of impact absorbing flooring as a fall-related injury intervention among frail elderly. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  7. Shatter Complex Formation in the Twin Craters Lava Flow, Zuni-Bandera Field, New Mexico

    NASA Astrophysics Data System (ADS)

    von Meerscheidt, H. C.; Bleacher, J. E.; Brand, B. D.; deWet, A.; Samuels, R.; Hamilton, C.; Garry, W. B.; Bandfield, J. L.

    2013-12-01

    Lava channels, tubes and sheets are transport structures that deliver flowing lava to a flow front. The type of structure can vary within a flow field and evolve throughout an eruption. The 18.0 × 1.0 ka Twin Craters lava flow in the Zuni-Bandera lava field provides a unique opportunity to study morphological changes of a lava flow partly attributable to interaction with a topographic obstacle. Facies mapping and airborne image analysis were performed on an area of the Twin Craters flow that includes a network of channels, lava tubes, shatter features, and disrupted pahoehoe flows surrounding a 45 m tall limestone bluff. The bluff is 1000 m long (oriented perpendicular to flow.) The general flow characteristics upstream from the bluff include smooth, lobate pahoehoe flows and a >2.5 km long lava tube (see Samuels et al., this meeting.) Emplacement characteristics change abruptly where the flow encountered the bluff, to include many localized areas of disrupted pahoehoe and several pahoehoe-floored depressions. Each depression is fully or partly surrounded by a raised rim of blocky material up to 4 m higher than the surrounding terrain. The rim is composed of 0.05 - 4 m diameter blocks, some of which form a breccia that is welded by lava, and some of which exhibit original flow textures. The rim-depression features are interpreted as shatter rings based on morphological similarity to those described by Orr (2011.Bul Volcanol.73.335-346) in Hawai';i. Orr suggests that shatter rings develop when fluctuations in the lava supply rate over-pressurize the tube, causing the tube roof to repeatedly uplift and subside. A rim of shattered blocks and breccias remains surrounding the sunken tube roof after the final lava withdraws from the system. One of these depressions in the Twin Craters flow is 240 m wide and includes six mounds of shattered material equal in height to the surrounding undisturbed terrain. Several mounds have depressed centers floored with rubbly pahoehoe. Prominent ';a';a channels travel around the bluff, leaving a 'wake' of uncovered ground on the downstream side. We interpret this shatter area to have been a branching tube network within an active sheet. The limestone bluff acted as an obstacle that caused a backup of lava within the tubes, driving episodes of shattering. The mounds likely represent earlier solidified sections between active, possibly braided, tube branches, which remained as mounds within the shatter area after the adjacent crust subsided. When lava broke out from the pressurized sheet-like lobe, it formed the ';a';a channels. This section of the flow field is interpreted using inferences from shatter ring formation, but is perhaps better termed a shatter sheet or shatter complex. This study has implications for understanding lava flow dynamics at constriction points, as well as the evolution and morphology of shatter rings.

  8. Composite pipe to metal joint

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Leslie, James C.; Leslie, II, James C.; Heard, James

    A method for making a metal to composite tube joint including selecting an elongated interior fitting constructed with an exterior barrel, reduced in exterior diameter to form a distally facing annular shoulder and then projecting still further distally to form an interior sleeve having a radially outwardly facing bonding surface. Selecting an elongated metal outer sleeve formed proximally with a collar constructed for receipt over the barrel and increased in interior diameter and projecting distally to form an exterior sleeve having a radially inwardly facing bonding surface cooperating with the first bonding surface to form an annulus receiving an extremitymore » of a composite tube and a bond bonding the extremity of the tube to the bonding surfaces.« less

  9. Dispersion of Multi-Walled Carbon Nanotubes in Skutterudites and Its Effect on Thermoelectric and Mechanical Properties.

    PubMed

    Schmitz, Andreas; Schmid, Carolin; de Boor, Johannes; Müller, Eckhard

    2017-03-01

    Filled cobalt-antimony based skutterudites have proven themselves as very promising thermoelectric materials for generator applications in an intermediate temperature range between 400 and 800 K due to their high figure of merit. Besides the functional thermoelectric properties also the skutterudites’ mechanical properties play an important role to withstand external mechanical and internal thermomechanical loads during operation. Properties of interest are hardness as well as fracture toughness and resistance to fatigue. Carbon nano tubes are well known for their high tensile strength and may therefore be used to increase the mechanical strength of composite materials. Additionally, the thermoelectric properties of the composite material might benefit from the high electrical conductivity of carbon nano tubes and increased phonon scattering at interfaces between matrix and carbon nano tube. A main precondition for benefiting from embedded nano-tubes is to achieve a homogeneous distribution of the CNTs and good adhesion between carbon nano tube and matrix material. In this work we present the influence of the introduction of multi-walled carbon nano tubes on the thermoelectric and mechanical properties of p-type skutterudites Ce(0.14)La(0.06)Co(2)Fe(2)Sb(12). The influence of different carbon nano tube concentrations and preparation routes on the resulting composite material’s thermoelectric, mechanical and microstructural properties is studied. A reduction of electrical and thermal conductivity as well as fracture strength is observed with increasing carbon nano tube content which is attributed to strong agglomeration of the nano tubes. The results underline the pivotal role of a homogeneous distribution of the carbon nano tubes for improving the mechanical properties of skutterudites.

  10. Protective coatings for composite tubes in space applications

    NASA Technical Reports Server (NTRS)

    Dursch, Harry W.; Hendricks, Carl L.

    1987-01-01

    Protective coatings for graphite/epoxy (Gr/Ep) tubular structures for a manned Space Station truss structure were evaluated. The success of the composite tube truss structure depends on its stability to long-term exposure to the low earth orbit (LEO) environment, with particular emphasis placed on atomic oxygen. Concepts for protectively coating Gr/Ep tubes include use of inorganic coated metal foils and electroplating. These coatings were applied to Gr/Ep tubes and then subjected to simulated LEO environment to evaluate survivability of coatings and coated tubes. Evaluation included: atomic oxygen resistance, changes in optical properties and adhesion, abrasion resistance, surface preparation required, coating uniformity, and formation of microcracks in the Gr/Ep tubes caused by thermal cycling. Program results demonstrated that both phosphoric and chromic acid anodized Al foil provided excellent adhesion to Gr/Ep tubes and exhibited stable optical properties when subjected to simulated LEO environment. The SiO2/Al coatings sputtered onto Al foils also resulted in an excellent protective coating. Electroplated Ni exhibited unacceptable adhesion loss to Gr/Ep tubes during atomic oxygen exposure.

  11. Protective coatings for composite tubes in space applications

    NASA Technical Reports Server (NTRS)

    Dursch, Harry W.; Hendricks, Carl L.

    1987-01-01

    Protective coatings for graphite/epoxy (Gr/Ep) tubular structures for a Manned Space Station truss structure were evaluated. The success of the composite tube truss structure depends on its stability to long-term exposure to the Low Earth Orbit (LEO) environment with particular emphasis placed on atomic oxygen. Concepts for protectively coating Gr/Ep tubes include use of inorganic coated metal foils and electroplating. These coatings were applied to Gr/Ep tubes and then subjected to simulated LEO environmnet to evaluate survivability of coatings and coated tubes. Evaluation included: atomic oxygen resistance, changes in optical properties and adhesion, abrasion resistancem surface preparation required, coating uniformity, and formation of microcracks in the Gr/Ep tubes caused by thermal cycling. Program results demonstrated that both phosphoric and chromic acid anodized Al foil provided excellent adhesion to Gr/Ep tubes and exhibited stable optical properties when subjected to simulated LEO environment. The SiO2/Al coatings speuttered onto Al foils also resulted in an excellent protective coating. Electroplated Ni exhibited unaccepatble adhesion loss to Gr/Ep tubes during atomic oxygen exposure.

  12. Stability of Evoked Potentials during Auditory Attention

    DTIC Science & Technology

    1988-12-01

    attention ef- (S2), to which the subject made a behavioral response and fects upon NI components of the evoked potential received food reinforcement for a... food dipper mounted in the floor, and a driver, with a sound tube attached, mounted in the top of the box. Histology Four weeks after surgery, the cats...response paradigm dose of intravenous sodium pentobarbital. Electrolytic lesions were using food reinforcement. They were gradually deprived of food

  13. 44. Building 102, view from mezzanine looking down to first ...

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

    44. Building 102, view from mezzanine looking down to first floor showing Klystron tube equipment vaults with dual waveguides leaving top of vaults through bifurcation combiner system at start of waveguides; note tops of capacitor vaults along photograph to left. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

  14. Anesthesia or Immobilization of Domestic and Miniature Swine - Methods and Some Problems.

    DTIC Science & Technology

    1972-12-01

    critical observation and moderate long-term survival before euthanasia and necropsy. Premedication and a gaseous anesthesia administered through a...Figure 1) were located outside and consistPd of 24 runs (12 runs per side) with sloped concrete floors and four-inch concrete dividers topped with...Jelly®) or sprayed with a slippery topical anesthetic (Cetacaine®). A plastic rod-type stiffener was inserted into the tube, and two persons were

  15. DOE ZERH Case Study: TC Legend Homes, Bellingham Power House, Bellingham, WA

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    none,

    Case study of a DOE 2015 Housing Innovation Award winning custom home in the marine climate that got HERS 34 without PV or HERS -12 with PV, with 6” SIP walls and 10” SIP roof; R-28 ICF around slab, R-20 rigid foam under slab; radiant floor heat and passive design; air-to-water heat pump COP 4.4; HRV; earth tube ventilation; triple-pane windows, 100% LED.

  16. Extrusion of metal oxide superconducting wire, tube or ribbon

    DOEpatents

    Dusek, Joseph T.

    1993-10-05

    A process for extruding a superconducting metal oxide composition YBa.sub.2 Cu.sub.3 O.sub.7-x provides a wire (tube or ribbon) having a cohesive mass and a degree of flexibility together with enhanced electrical properties. Wire diameters in the range of 6-85 mils have been produced with smaller wires on the order of 10 mils in diameter exhibiting enhanced flexibility for forming braided, or multistrand, configurations for greater current carrying capacity. The composition for extrusion contains a polymeric binder to provide a cohesive mass to bind the particles together during the extrusion process with the binder subsequently removed at lower temperatures during sintering. The composition for extrusion further includes a deflocculent, an organic plasticizer and a solvent which also are subsequently removed during sintering. Electrically conductive tubing with an inner diameter of 52 mil and an outer diameter of 87-355 mil has also been produced. Flat ribbons have been produced in the range of 10-125 mil thick by 100-500 mil wide. The superconducting wire, tube or ribbon may include an outer ceramic insulating sheath co-extruded with the wire, tubing or ribbon.

  17. Extrusion of metal oxide superconducting wire, tube or ribbon

    DOEpatents

    Dusek, Joseph T.

    1993-01-01

    A process for extruding a superconducting metal oxide composition YBa.sub.2 Cu.sub.3 O.sub.7-x provides a wire (tube or ribbon) having a cohesive mass and a degree of flexibility together with enhanced electrical properties. Wire diameters in the range of 6-85 mils have been produced with smaller wires on the order of 10 mils in diameter exhibiting enhanced flexibility for forming braided, or multistrand, configurations for greater current carrying capacity. The composition for extrusion contains a polymeric binder to provide a cohesive mass to bind the particles together during the extrusion process with the binder subsequently removed at lower temperatures during sintering. The composition for extrusion further includes a deflocculent, an organic plasticizer and a solvent which also are subsequently removed during sintering. Electrically conductive tubing with an inner diameter of 52 mil and an outer diameter of 87-355 mil has also been produced. Flat ribbons have been produced in the range of 10-125 mil thick by 100-500 mil wide. The superconducting wire, tube or ribbon may include an outer ceramic insulating sheath co-extruded with the wire, tubing or ribbon.

  18. An ignimbrite caldera from the bottom up: Exhumed floor and fill of the resurgent Bonanza caldera, Southern Rocky Mountain volcanic field, Colorado

    USGS Publications Warehouse

    Lipman, Peter W.; Zimmerer, Matthew J.; McIntosh, William C.

    2015-01-01

    Among large ignimbrites, the Bonanza Tuff and its source caldera in the Southern Rocky Mountain volcanic field display diverse depositional and structural features that provide special insights concerning eruptive processes and caldera development. In contrast to the nested loci for successive ignimbrite eruptions at many large multicyclic calderas elsewhere, Bonanza caldera is an areally isolated structure that formed in response to a single ignimbrite eruption. The adjacent Marshall caldera, the nonresurgent lava-filled source for the 33.9-Ma Thorn Ranch Tuff, is the immediate precursor for Bonanza, but projected structural boundaries of two calderas are largely or entirely separate even though the western topographic rim of Bonanza impinges on the older caldera. Bonanza, source of a compositionally complex regional ignimbrite sheet erupted at 33.12 ± 0.03 Ma, is a much larger caldera system than previously recognized. It is a subequant structure ∼20 km in diameter that subsided at least 3.5 km during explosive eruption of ∼1000 km3 of magma, then resurgently domed its floor a similar distance vertically. Among its features: (1) varied exposure levels of an intact caldera due to rugged present-day topography—from Paleozoic and Precambrian basement rocks that are intruded by resurgent plutons, upward through precaldera volcanic floor, to a single thickly ponded intracaldera ignimbrite (Bonanza Tuff), interleaved landslide breccia, and overlying postcollapse lavas; (2) large compositional gradients in the Bonanza ignimbrite (silicic andesite to rhyolite ignimbrite; 60%–76% SiO2); (3) multiple alternations of mafic and silicic zones within a single ignimbrite, rather than simple upward gradation to more mafic compositions; (4) compositional contrasts between outflow sectors of the ignimbrite (mainly crystal-poor rhyolite to east, crystal-rich dacite to west); (5) similarly large compositional diversity among postcollapse caldera-fill lavas and resurgent intrusions; (6) brief time span for the entire caldera cycle (33.12 to ca. 33.03 Ma); (7) an exceptionally steep-sided resurgent dome, with dips of 40°–50° on west and 70°–80° on northeast flanks. Some near-original caldera morphology has been erosionally exhumed and remains defined by present-day landforms (western topographic rim, resurgent core, and ring-fault valley), while tilting and deep erosion provide three-dimensional exposures of intracaldera fill, floor, and resurgent structures. The absence of Plinian-fall deposits beneath proximal ignimbrites at Bonanza and other calderas in the region is interpreted as evidence for early initiation of pyroclastic flows, rather than lack of a high eruption column. Although the absence of a Plinian deposit beneath some ignimbrites elsewhere has been interpreted to indicate that abrupt rapid foundering of the magma-body roof initiated the eruption, initial caldera collapse began at Bonanza only after several hundred kilometers of rhyolitic tuff had erupted, as indicated by the minor volume of this composition in the basal intracaldera ignimbrite. Caldera-filling ignimbrite has been largely stripped from the southern and eastern flank of the Bonanza dome, exposing large areas of caldera-floor as a structurally coherent domed plate, bounded by ring faults with locations that are geometrically closely constrained even though largely concealed beneath valley alluvium. The structurally coherent floor at Bonanza contrasts with fault-disrupted floors at some well-exposed multicyclic calderas where successive ignimbrite eruptions caused recurrent subsidence. Floor rocks at Bonanza are intensely brecciated within ∼100 m inboard of ring faults, probably due to compression and crushing of the subsiding floor in proximity to steep inward-dipping faults. Upper levels of the floor are locally penetrated by dike-like crack fills of intracaldera ignimbrite, interpreted as dilatant fracture fills rather than ignimbrite vents. The resurgence geometry at Bonanza has implications for intracaldera-ignimbrite volume; this parameter may have been overestimated at some young calderas elsewhere, with bearing on outflow-intracaldera ratios and times of initial caldera collapse. Such features at Bonanza provide insights for interpreting calderas universally, with respect to processes of caldera collapse and resurgence, inception of subsidence in relation to progression of the ignimbrite eruption, complications with characterizing structural versus topographic margins of calderas, contrasts between intra- versus extracaldera ignimbrite, and limitations in assessing volumes of large caldera-forming eruptions. Bonanza provides a rare site where intact caldera margins and floor are exhumed and exposed, providing valuable perspectives for understanding younger similar calderas in some of the world’s most active and dangerous silicic provinces.

  19. Anthropogenic and natural disturbances to marine benthic communities in Antarctica

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lenihan, H.; Oliver, J.S.

    1995-05-01

    Sampling and field experiments were conducted from 1975 to 1990 to test how the structure of marine benthic communities around McMurdo Station, Antarctica varied with levels of anthropogenic contaminants in marine sediments. The structure of communities (e.g., infauna density, species composition, and life history characteristics) in contaminated and uncontaminated areas were compared with the structure of communities influenced by two large-scale natural disturbances, anchor ice formation and uplift or iceberg scour. Benthic communities changed radically along a steep spatial gradient of anthropogenic hydrocarbon, metal, and PCB contamination around McMurdo Station. The heavily contaminated end of the gradient, Winter Quarters Bay,more » was low in infaunal and epifaunal abundance and was dominated by a few opportunistic species of polychaete worms. The edge of the heavily contaminated bay, the transition area, contained several motile polychaete species with less opportunistic life histories. Uncontaminated sedimentary habitats harbored dense tube mats of infaunal animals numerically dominated by populations of polychaete worms, crustaceans, and a large suspension feeding bivalve. These species are generally large and relatively sessile, except for several crustacean species living among the tubes. Although the community patterns around anthropogenic and natural disturbances were similar, particularly motile and opportunistic species at heavily disturbed and marginal areas, the natural disturbances cover much greater areas of the sea floor about the entire Antarctic continent. On the other hand, recovery from chemical contamination is likely to take many more decades than recovery from natural disturbances as contaminant degradation is a slow process. 77 refs., 6 figs., 5 tabs.« less

  20. Characterization of mechanical properties of hydroxyapatite-silicon-multi walled carbon nano tubes composite coatings synthesized by EPD on NiTi alloys for biomedical application.

    PubMed

    Khalili, Vida; Khalil-Allafi, Jafar; Sengstock, Christina; Motemani, Yahya; Paulsen, Alexander; Frenzel, Jan; Eggeler, Gunther; Köller, Manfred

    2016-06-01

    Release of Ni(1+) ions from NiTi alloy into tissue environment, biological response on the surface of NiTi and the allergic reaction of atopic people towards Ni are challengeable issues for biomedical application. In this study, composite coatings of hydroxyapatite-silicon multi walled carbon nano-tubes with 20wt% Silicon and 1wt% multi walled carbon nano-tubes of HA were deposited on a NiTi substrate using electrophoretic methods. The SEM images of coated samples exhibit a continuous and compact morphology for hydroxyapatite-silicon and hydroxyapatite-silicon-multi walled carbon nano-tubes coatings. Nano-indentation analysis on different locations of coatings represents the highest elastic modulus (45.8GPa) for HA-Si-MWCNTs which is between the elastic modulus of NiTi substrate (66.5GPa) and bone tissue (≈30GPa). This results in decrease of stress gradient on coating-substrate-bone interfaces during performance. The results of nano-scratch analysis show the highest critical distance of delamination (2.5mm) and normal load before failure (837mN) as well as highest critical contact pressure for hydroxyapatite-silicon-multi walled carbon nano-tubes coating. The cell culture results show that human mesenchymal stem cells are able to adhere and proliferate on the pure hydroxyapatite and composite coatings. The presence of both silicon and multi walled carbon nano-tubes (CS3) in the hydroxyapatite coating induce more adherence of viable human mesenchymal stem cells in contrast to the HA coated samples with only silicon (CS2). These results make hydroxyapatite-silicon-multi walled carbon nano-tubes a promising composite coating for future bone implant application. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. A numerical approach to model and predict the energy absorption and crush mechanics within a long-fiber composite crush tube

    NASA Astrophysics Data System (ADS)

    Pickett, Leon, Jr.

    Past research has conclusively shown that long fiber structural composites possess superior specific energy absorption characteristics as compared to steel and aluminum structures. However, destructive physical testing of composites is very costly and time consuming. As a result, numerical solutions are desirable as an alternative to experimental testing. Up until this point, very little numerical work has been successful in predicting the energy absorption of composite crush structures. This research investigates the ability to use commercially available numerical modeling tools to approximate the energy absorption capability of long-fiber composite crush tubes. This study is significant because it provides a preliminary analysis of the suitability of LS-DYNA to numerically characterize the crushing behavior of a dynamic axial impact crushing event. Composite crushing theory suggests that there are several crushing mechanisms occurring during a composite crush event. This research evaluates the capability and suitability of employing, LS-DYNA, to simulate the dynamic crush event of an E-glass/epoxy cylindrical tube. The model employed is the composite "progressive failure model", a much more limited failure model when compared to the experimental failure events which naturally occur. This numerical model employs (1) matrix cracking, (2) compression, and (3) fiber breakage failure modes only. The motivation for the work comes from the need to reduce the significant cost associated with experimental trials. This research chronicles some preliminary efforts to better understand the mechanics essential in pursuit of this goal. The immediate goal is to begin to provide deeper understanding of a composite crush event and ultimately create a viable alternative to destructive testing of composite crush tubes.

  2. Changes in necromass and nutrients on the forest floor of a palm floodplain forest in the Luquillo mountains of Puerto Rico.

    Treesearch

    ARIEL E. LUGO; JORGE L. FRANGI

    2003-01-01

    We studied changes that occurred between 1980 and 2000 in forest floor biomass (necromass+ biomass of herbaceous plants), nutrient stocks, and plant composition of a Prestoea montana floodplain forest. The forest was located in the Luquillo Mountains of Puerto Rico. Several storms and hurricanes passed near the study site during that period, the most severe being...

  3. Differences in bacterial composition between men's and women's restrooms and other common areas within a public building.

    PubMed

    Dobbler, Priscila Caroline Thiago; Laureano, Álvaro Macedo; Sarzi, Deise Schroder; Cañón, Ehidy Rocio Peña; Metz, Geferson Fernando; de Freitas, Anderson Santos; Takagaki, Beatriz Midori; D Oliveira, Cristiane Barbosa; Pylro, Victor Satler; Copetti, André Carlos; Victoria, Filipe; Redmile-Gordon, Marc; Morais, Daniel Kumazawa; Roesch, Luiz Fernando Wurdig

    2018-04-01

    Humans distribute a wide range of microorganisms around building interiors, and some of these are potentially pathogenic. Recent research established that humans are the main drivers of the indoor microbiome and up to now significant literature has been produced about this topic. Here we analyzed differences in bacterial composition between men's and women's restrooms and other common areas within the same public building. Bacterial DNA samples were collected from restrooms and halls of a three-floor building from the Federal University of Pampa, RS, Brazil. The bacterial community was characterized by amplification of the V4 region of the 16S rRNA gene and sequencing. Throughout all samples, the most abundant phylum was Proteobacteria, followed by Actinobacteria, Bacteroidetes and Firmicutes. Beta diversity metrics showed that the structure of the bacterial communities were different among the areas and floors tested, however, only 6-9% of the variation in bacterial communities was explained by the area and floors sampled. A few microorganisms showed significantly differential abundance between men's and women's restrooms, but in general, the bacterial communities from both places were very similar. Finally, significant differences among the microbial community profile from different floors were reported, suggesting that the type of use and occupant demographic within the building may directly influence bacterial dispersion and establishment.

  4. Geological Interpretation of the Sea Floor Offshore of Edgartown, Massachusetts

    USGS Publications Warehouse

    Poppe, L.J.; McMullen, K.Y.; Foster, D.S.; Blackwood, D.S.; Williams, S.J.; Ackerman, S.D.; Moser, M.S.; Glomb, K.A.

    2010-01-01

    Gridded bathymetry and sidescan-sonar imagery together cover approximately 37.3 square kilometers of sea floor in the vicinity of Edgartown Harbor, Massachusetts. Although originally collected for charting purposes during National Oceanic and Atmospheric Administration hydrographic survey H11346, these acoustic data, and the sea-floor stations and seismic-reflection lines subsequently occupied to verify them, 1) show the composition and terrain of the seabed, 2) provide information on sediment transport and benthic habitat, and 3) are part of an expanding series of studies that provide a fundamental framework for research and management (for example, windfarms, pipelines, and dredging) activities along the Massachusetts inner continental shelf.

  5. Vapor cooled current lead for cryogenic electrical equipment

    DOEpatents

    Vansant, James H.

    1983-01-01

    Apparatus and method are provided for conducting electric current to cryogenic electrical equipment devices. A combination of inner and outer tubes together form a plurality of hollow composite tubes housed in a sheath. Top and bottom block mounting means are fitted to hold the composite tubes and are affixed to the ends of the sheath. This combination forms a current lead. The current lead is attached to a cryogenic device housing a fluid coolant which moves through the current lead, cooling the current lead as the fluid travels.

  6. Validation of an interior noise prediction model for a composite cylinder

    NASA Technical Reports Server (NTRS)

    Beyer, Todd B.; Grosveld, Ferdinand W.

    1987-01-01

    An acoustic modal analysis has been performed in the cavity of a composite cylinder model of an aircraft fuselage. The filament wound, composite shell is 12 feet long and 5.5 feet in diameter. A one-half-in. thick plywood floor is attached to the shell 69 deg from the vertical centerline through the bottom of the shell. The acoustic modal frequencies were obtained from a sound pressure level and phase survey conducted throughout the interior volume bounded by the floor, endcaps and stiffened shell, while being excited by white noise from a loudspeaker source. The measured acoustic resonance frequencies and mode shapes compare well with analytical predictions from the Propeller Aircraft Interior Noise (PAIN) model. Details of the theory and derivation of the acoustic characteristics have been included. Reverberation time measurements, using the integrated impulse technique, have been performed to determine acoustic loss factors. These measured loss factors have been input to the PAIN program in order to more accurately predict the space-averaged interior noise of the composite cylinder.

  7. Collapse of composite tubes under end moments

    NASA Technical Reports Server (NTRS)

    Stockwell, Alan E.; Cooper, Paul A.

    1992-01-01

    Cylindrical tubes of moderate wall thickness such as those proposed for the original space station truss, may fail due to the gradual collapse of the tube cross section as it distorts under load. Sometimes referred to as the Brazier instability, it is a nonlinear phenomenon. This paper presents an extension of an approximate closed form solution of the collapse of isotropic tubes subject to end moments developed by Reissner in 1959 to include specially orthotropic material. The closed form solution was verified by an extensive nonlinear finite element analysis of the collapse of long tubes under applied end moments for radius to thickness ratios and composite layups in the range proposed for recent space station truss framework designs. The finite element analysis validated the assumption of inextensional deformation of the cylindrical cross section and the approximation of the material as specially orthotropic.

  8. An edrioasteroid from the Silurian Herefordshire Lagerstätte of England reveals the nature of the water vascular system in an extinct echinoderm.

    PubMed

    Briggs, Derek E G; Siveter, Derek J; Siveter, David J; Sutton, Mark D; Rahman, Imran A

    2017-09-13

    Echinoderms are unique in having a water vascular system with tube feet, which perform a variety of functions in living forms. Here, we report the first example of preserved tube feet in an extinct group of echinoderms. The material, from the Silurian Herefordshire Lagerstätte, UK, is assigned to a new genus and species of rhenopyrgid edrioasteroid, Heropyrgus disterminus The tube feet attach to the inner surface of compound interradial plates and form two sets, an upper and a lower, an arrangement never reported previously in an extant or extinct echinoderm. Cover plates are absent and floor plates are separated creating a large permanent entrance to the interior of the oral area. The tube feet may have captured food particles that entered the oral area and/or enhanced respiration. The pentameral symmetry of the oral surface transitions to eight columns in which the plates are vertically offset resulting in a spiral appearance. This change in symmetry may reflect flexibility in the evolutionary development of the axial and extraxial zones in early echinoderm evolution. © 2017 The Author(s).

  9. Feasibility of Shape-Memory Ni/Ti Alloy Wire Containing Tube Elevators for Transcrestal Detaching Maxillary Sinus Mucosa: Ex Vivo Study.

    PubMed

    Li, Yanfeng; Wang, Fuli; Hu, Pin; Fan, Jiadong; Han, Yishi; Liu, Bin; Liu, Tao; Yang, Chunhao; Gu, Xiangmin

    2016-01-01

    Osteotome sinus floor elevation is a less invasive approach to augment an insufficient alveolar bone at the posterior maxilla for dental implantation. However, this approach has some limitations due to the lack of sinus lift tools available for clinical use and the small transcrestal access to the maxillary sinus floor. We recently invented shape-memory Ni/Ti alloy wire containing tube elevators for transcrestal detaching maxillary sinus mucosa, and developed goat ex vivo models for direct visualizing the effectiveness of detaching sinus mucosa in real time during transcrestal maxillary sinus floor elevation. We evaluated our invented elevators, namely elevator 012 and elevator 014, for their effectiveness for transcrestal detaching maxillary sinus mucosa using the goat ex vivo models. We measured the length of sinus mucosa detached in mesial and distal directions or buccal and palatal directions, and the space volume created by detaching maxillary sinus mucosa in mesial, distal, buccal and palatal directions using the invented elevators. Elevator 012 had a shape-memory Ni/Ti alloy wire with a diameter of 0.012 inch, while elevator 014 had its shape-memory Ni/Ti alloy wire with a diameter of 0.014 inch. Elevator 012 could detach the goat maxillary sinus mucosa in the mesial or distal direction for 12.1±4.3 mm, while in the buccal or palatal direction for 12.5±6.7 mm. The elevator 014 could detach the goat maxillary sinus mucosa for 23.0±4.9 mm in the mesial or distal direction, and for 19.0±8.1 mm in the buccal or palatal direction. An average space volume of 1.7936±0.2079 ml was created after detaching the goat maxillay sinus mucosa in both mesial/distal direction and buccal/palatal direction using elevator 012; while the average space volume created using elevator 014 was 1.8764±0.2366 ml. Both two newly invented tube elevators could effectively detach the maxillary sinus mucosa on the goat ex vivo sinus models. Moreover, elevator 014 has advantages over the elevator 012 for the capability to detach sinus mucosa. © 2016 The Author(s) Published by S. Karger AG, Basel.

  10. Mud volcano venting induced gas hydrate formation at the upper slope accretionary wedge, offshore SW Taiwan

    NASA Astrophysics Data System (ADS)

    Lin, Saulwood; Tseng, Yi-Ting; Cheng, Wan-Yen; Chou, Cheng-Tien; Chen, NeiChen; Hsieh, I.-Chih

    2016-04-01

    TsanYao Mud Volcano (TYMV) is the largest mud volcano cone in the Hengchun Mud Volcano Group (HCMVG), located at the upper slope of the accrretionary wedge, southwest of Taiwan. The region is under active tectonic activity with the Philippine Plate, moving northwestward at a rate of ~8 cm/year. This region also receives huge quantity of suspended particle load of ~100 mT/year at present time from adjacent small rivers of the Island of Taiwan. Large loads of suspended sediments influx become a major source of organic carbon and later gas and other hydrocarbon. Gas and fluid in the mud volcano are actively venting from deep to the sea floor on the upper slope of the accretionary wedge. In order to understand venting on the HCMVG, echo sounder, towcam and coring were carried out. Pore water sulfate, chloride, potassium, calcium, stable isotope O-18, gas compositions, dissolved sulfide were analysed. The HCMVG consists of 12 volcano cones of different sizes. Large quantity of gas and fluid are venting directly from deep to the TYMV structure high, as well as 50+ other vents as appeared as flares on the echo sounder. Some flares are reaching to the atmosphere and likely a source of green house gases to the atmosphere. Venting fluids include gas bubbles, suspended particle, mud, and breccia. Breccia size could reach more than 12 cm in diameter. Circular bands in different color appeared around the cone may represent stages of vent eruptions. Compositions of vent gas include methane, ethane and propane. High proportions of ethane and propane in the vent gas demonstrated that source of gas are thermogenic in origin. Patchy authigenic carbonate, bacterial mats, bivalves, tube worms and other chemosynthesis organisms were supported by venting gas AOM process near the sea floor. Pore water chloride concentrations show distinct variation pattern from center cone to the side of the volcano, with low in the center and high away from the cone. Pore water with higher than seawater chloride indicated gas hydrate formation in sediments away from the mud volcano cone.

  11. RP-1 and JP-8 Thermal Stability Experiments

    NASA Technical Reports Server (NTRS)

    Brown, Sarah P.; Emens, Jessica M.; Frederick, Robert A., Jr.

    2005-01-01

    This work experimentally investigates the effect of fuel composition changes on jet and rocket fuel thermal stability. A High Reynolds Number Thermal Stability test device evaluated JP-8 and RP-1 fuels. The experiment consisted of an electrically heated, stainless steel capillary tube with a controlled fuel outlet temperature. An optical pyrometer monitored the increasing external temperature profiles of the capillary tube as deposits build inside during each test. Multiple runs of each fuel composition provided results on measurement repeatability. Testing a t two different facilities provided data on measurement reproducibility. The technique is able to distinguish between thermally stable and unstable compositions of JP-8 and intermediate blends made by combining each composition. The technique is also able to distinguish among standard RP-1 rocket fuels and those having reduced sulfur levels. Carbon burn off analysis of residue in the capillary tubes on the RP-1 fuels correlates with the external temperature results.

  12. Polarization Lidar for Shallow Water Supraglacial Lake Depth Measurement

    NASA Astrophysics Data System (ADS)

    Mitchell, S.; Adler, J.; Thayer, J. P.; Hayman, M.

    2010-12-01

    A bathymetric, polarization lidar system transmitting at 532 nanometers and using a single photomultiplier tube is developed for applications of shallow water depth measurement, in particular those often found in supraglacial lakes of the ablation zone on the Greenland Ice Sheet. The technique exploits polarization attributes of the probed water body to isolate surface and floor returns, enabling constant fraction detection schemes to determine depth. The minimum resolvable water depth is no longer dictated by the system’s laser or detector pulse width and can achieve better than an order of magnitude improvement over current water depth determination techniques. In laboratory tests, a Nd:YAG microchip laser coupled with polarization optics, a photomultiplier tube, a constant fraction discriminator and a time to digital converter are used to target various water depths, using ice as the floor to simulate a supraglacial lake. Measurement of 1 centimeter water depths with an uncertainty of ±3 millimeters are demonstrated using the technique. This novel technique enables new approaches to designing laser bathymetry systems for shallow depth determination from remote platforms while not compromising deep water depth measurement, and will support comprehensive hydrodynamic studies of supraglacial lakes. Additionally, the compact size and low weight (<15 kg) of the field system currently in development presents opportunities for use in small unmanned aircraft systems (UAS) for large areal surveys of the ablation zone.

  13. Torsional actuation with extension-torsion composite coupling and a magnetostrictive actuator

    NASA Astrophysics Data System (ADS)

    Bothwell, Christopher M.; Chandra, Ramesh; Chopra, Inderjit

    1995-04-01

    An analytical-experimental study of using magnetostrictive actuators in conjunction with an extension-torsion coupled composite tube to actuate a rotor blade trailing-edge flap to actively control helicopter vibration is presented. Thin walled beam analysis based on Vlasov theory was used to predict the induced twist and extension in a composite tube with magnetostrictive actuation. The study achieved good correlation between theory and experiment. The Kevlar-epoxy systems showed good correlation between measured and predicted twist values.

  14. An experimental study of the composite CNT/copper coating

    NASA Astrophysics Data System (ADS)

    Panarin, Valentin Ye.; Svavil‧nyi, Nikolai Ye.; Khominich, Anastasiya I.

    2018-03-01

    This paper presents experimental results on the preparation and investigation of the carbon nanotubes-copper composite material. Carbon nanotubes (CNTs) were synthesized on silicon substrates by the chemical vapor deposition (CVD) method and then filled with copper by evaporation from a melting pot in a vacuum. Copper evenly covered both the surface of the entangled tubes and the free substrate surface between the tubes. To improve the adhesion of tubes and matrix material, a carbon substructure was grown on the surface of tubes by adding working gas plasma to the CNT synthesis area. It is proposed to use a copper coating as a diffusion barrier upon subsequent filling of the reinforcing CNT frame by a carbide-forming materials matrix with predetermined physico-mechanical and tribological properties.

  15. Combined mechanical loading of composite tubes

    NASA Technical Reports Server (NTRS)

    Derstine, Mark S.; Pindera, Marek-Jerzy; Bowles, David E.

    1988-01-01

    An analytical/experimental investigation was performed to study the effect of material nonlinearities on the response of composite tubes subjected to combined axial and torsional loading. The effect of residual stresses on subsequent mechanical response was included in the investigation. Experiments were performed on P75/934 graphite-epoxy tubes with a stacking sequence of (15/0/ + or - 10/0/ -15), using pure torsion and combined axial/torsional loading. In the presence of residual stresses, the analytical model predicted a reduction in the initial shear modulus. Experimentally, coupling between axial loading and shear strain was observed in laminated tubes under combined loading. The phenomenon was predicted by the nonlinear analytical model. The experimentally observed linear limit of the global shear response was found to correspond to the analytically predicted first ply failure. Further, the failure of the tubes was found to be path dependent above a critical load level.

  16. Crushing characteristics of composite tubes with 'near-elliptical' cross sections

    NASA Astrophysics Data System (ADS)

    Farley, Gary L.; Jones, Robert M.

    1992-01-01

    An experimental investigation was conducted to determine whether the energy-absorption capability of near-elliptical cross-section composite tubular specimens is a function of included angle. Each half of the near-elliptical cross-section tube is a segment of a circle. The included angle is the angle created by radial lines extending from the center of the circular segment to the ends of the circular segment. Graphite- and Kevlar-reinforced epoxy material was used to fabricate specimens. Tube internal diameters were 2.54, 3.81, and 7.62 cm, and included angles were 180, 160, 135, and 90 degrees. Based upon the test results from these tubes, energy-absorption capability increased between 10 and 30 percent as included angle decreased between 180 and 90 degrees for the materials evaluated. Energy-absorption capability was a decreasing nonlinear function of the ratio of tube internal diameter to wall thickness.

  17. Electro-thermo-mechanical nonlinear nonlocal vibration and instability of embedded micro-tube reinforced by BNNT, conveying fluid

    NASA Astrophysics Data System (ADS)

    Ghorbanpour Arani, A.; Shajari, A. R.; Amir, S.; Loghman, A.

    2012-08-01

    Nonlinear vibration and stability of a smart composite micro-tube made of Poly-vinylidene fluoride (PVDF) reinforced by Boron-Nitride nanotubes (BNNTs) embedded in an elastic medium under electro-thermal loadings is investigated. The BNNTs are considered to be long straight fibers and the composite used in this study is in the category of piezoelectric fiber reinforced composites (PEFRC). The micro-tube is conveying a fully developed isentropic, incompressible and irrotational fluid flow. The smart micro-tube is modeled as a thin shell based on the nonlinear Donnell's shell theory. Effects of mean flow velocity, fluid viscosity, elastic medium modulus, temperature change, imposed electric potential, small scale, aspect ratio, volume percent and orientation angle of the BNNTs on the vibration behavior of the micro-tube are taken into account. The results indicate that increasing mean flow velocity considerably increases the nonlinearity effects so that small scale and temperature change effects become negligible. It has also been found that stability of the system is strongly dependent on the imposed electric potential and the volume percent of BNNTs reinforcement. The system studied in this article can be used as sensor and actuator in the sensitive applications.

  18. The use of temperature programmable flow tubes for the study of atmospheric aerosols

    NASA Astrophysics Data System (ADS)

    Khalizov, A.; Sloan, J. J.

    2003-04-01

    In order to understand the response of atmospheric aerosols to changes they encounter in the natural atmosphere, it is usually necessary to observe models of these aerosol systems under carefully controlled laboratory conditions. This is particularly difficult for the condensed phase, for which agglomeration, gas-particle exchange and gravitational settling affect the composition and limit the observation time. Traditionally, studies of this kind have been carried out in large static chambers and flow tubes. While large chambers provide relatively long observations times, they afford the experimenter less direct control over the environment of the particles. Flow tubes, on the other hand provide very precise control of the experimental conditions, but a much shorter contact time. We have used temperature programmable flow tubes for the past decade to study the composition, size and phase changes that occur when aerosols are exposed to variations in the temperature and composition of the surrounding atmosphere. In many cases, our measurements also yield accurate rate constants for the nucleation of solids in liquid droplets. In this presentation, we will illustrate the capabilities of this method using results obtained from a new temperature programmable flow tube recently built in our laboratory.

  19. Use of multi-coil parallel-gap resonators for co-registration EPR/NMR imaging

    NASA Astrophysics Data System (ADS)

    Kawada, Yuuki; Hirata, Hiroshi; Fujii, Hirodata

    2007-01-01

    This article reports experimental investigations on the use of RF resonators for continuous-wave electron paramagnetic resonance (cw-EPR) and proton nuclear magnetic resonance (NMR) imaging. We developed a composite resonator system with multi-coil parallel-gap resonators for co-registration EPR/NMR imaging. The resonance frequencies of each resonator were 21.8 MHz for NMR and 670 MHz for EPR. A smaller resonator (22 mm in diameter) for use in EPR was placed coaxially in a larger resonator (40 mm in diameter) for use in NMR. RF magnetic fields in the composite resonator system were visualized by measuring a homogeneous 4-hydroxy-2,2,6,6-tetramethyl-piperidinooxy (4-hydroxy-TEMPO) solution in a test tube. A phantom of five tubes containing distilled water and 4-hydroxy-TEMPO solution was also measured to demonstrate the potential usefulness of this composite resonator system in biomedical science. An image of unpaired electrons was obtained for 4-hydroxy-TEMPO in three tubes, and was successfully mapped on the proton image for five tubes. Technical problems in the implementation of a composite resonator system are discussed with regard to co-registration EPR/NMR imaging for animal experiments.

  20. Impact and appreciation of two methods aiming at reducing hazardous drug environmental contamination: The centralization of the priming of IV tubing in the pharmacy and use of a closed-system transfer device.

    PubMed

    Guillemette, Annie; Langlois, Hélène; Voisine, Maxime; Merger, Delphine; Therrien, Roxane; Mercier, Genevieve; Lebel, Denis; Bussières, Jean-François

    2014-12-01

    The main objective was to evaluate the impact of two methods aiming at reducing hazardous drug environmental contamination: the centralization of the priming of IV tubing in the pharmacy and the use of a closed-system transfer device. The secondary objective was to evaluate the satisfaction of pharmacy technicians using a survey. Sites in the hematology-oncology satellite pharmacy and care unit were analyzed for the presence of cyclophosphamide, ifosfamide and methotrexate before and after the centralization of the priming of IV tubing in the pharmacy and before and after using a closed-system transfer device. The limits of detection for cyclophosphamide, ifosfamide and methotrexate were, respectively, of 0.0015 ng/cm(2), 0.0012 ng/cm(2) and 0.0060 ng/cm(2). The pharmacy technician satisfaction was evaluated using a questionnaire. A total of 225 samples was quantified. After the centralization of priming in the pharmacy, no significant difference was found in the proportion of positive samples for cyclophosphamide, ifosfamide and methotrexate. Traces of cyclophosphamide found on the floor in patient care areas was significantly reduced (median[min-max] 0.08[0.06-0.09]ng/cm(2) vs. 0.03[0.02-0.05], p < 0.0001). After using a closed-system transfer device, a significant difference was found for the proportion of cyclophosphamide positive samples (15/45(33%) vs. 0/45(0%), p < 0.0001), but no significant difference was found for ifosfamide (12/45(27%) vs. 5/45(11%), p = 0.059) and methotrexate (1/45(2%) vs. 2/45(4%), p = 0.557). Pharmacy technicians raised issues following the centralization of priming (e.g. workload) and the use of closed-system transfer devices (e.g. spills, particles, workload and handling difficulties). The centralization of the priming of IV tubing in the pharmacy reduced floor contamination in patient care areas without increasing surface contamination in the pharmacy. Closed-system transfer devices reduced contamination in pharmacy, but handling issues were raised by pharmacy technicians. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  1. Small mammals in young forests: implications for management for sustainability.

    Treesearch

    A.B. Carey; C.A. Harrington

    2001-01-01

    Small mammals have been proposed as indicators of sustainability in forests in the Pacific Northwest and elsewhere. Mammal community composition and species abundances purportedly result from interactions among species, forest-floor characteristics, large coarse woody debris, understory vegetation, and overstory composition. Coarse woody debris is thought to be...

  2. Sea-floor geology and topography offshore in northeastern Long Island Sound

    USGS Publications Warehouse

    Poppe, L.J.; McMullen, K.Y.; Ackerman, S.D.; Glomb, K.A.

    2013-01-01

    Datasets of gridded multibeam bathymetry, covering approximately 52.9 square kilometers, were used to interpret character and geology of the sea floor in northeastern Long Island Sound. Although originally collected for charting purposes during National Oceanic and Atmospheric Administration hydrographic survey H12012, these acoustic data and the sea-floor sampling and photography stations subsequently occupied to verify the acoustic data are interpreted (1) to define the composition and terrain of the seabed, (2) to provide information on sediment transport and benthic habitat, and (3) as part of an expanding series of studies that provide a fundamental framework for research and resource management (for example, cables, pipelines, and dredging) activities in this major east coast estuary.

  3. Compositional-Spread Discovery of Catalysts for the Growth of Long-Length Dense Forests of Vertically Aligned Carbon Nanotubes

    NASA Astrophysics Data System (ADS)

    Christen, Hans M.; Puretzky, Alex A.; Cui, Hongtao; Lowndes, Douglas H.; Belay, Kalayu; Geohegan, David B.

    2004-03-01

    The growth of dense forests of vertically aligned arrays of multi-walled carbon nanotubes (VAA-MWNTs) by chemical vapor deposition [CVD] from a single metallic catalyst layer typically self-terminates after only a few hundred microns of tube length. In order to obtain maximal growth to long lengths, a systematic simultaneous study of catalyst composition and thickness is needed performed here by a compositional-spread approach. Using Pulsed-Laser Deposition (PLD), metallic layers with a wedge-shaped thickness profile are deposited onto Al-coated silicon substrates. High temperature annealing of the metal catalyst films in flowing Ar/H2 gas followed by the one-hour growth of VA-MWNTs by CVD using acetylene gas yields VAA-MWNTs. Tube height (and thus the catalytic activity) is determined as function of position and can be analyzed as a function of catalyst thickness and composition. A dependence of tube height as function of catalyst composition (Mo/Fe ratio) demonstrates that a specific catalyst composition exhibits a local maximum in catalytic activity, permitting the extension of nanotube array growth up to 4 millimeters in height. Other combinations of catalysts and the growth of single-walled tubes will be discussed. This research was sponsored by the U.S. Department of Energy under contract DE-AC05-00OR22725 with the Oak Ridge National Laboratory, managed by UT-Battelle, LLC, and the Laboratory-Directed Research and Development Program at ORNL.

  4. The influence of chemical composition of LNG on the supercritical heat transfer in an intermediate fluid vaporizer

    NASA Astrophysics Data System (ADS)

    Xu, Shuangqing; Chen, Xuedong; Fan, Zhichao; Chen, Yongdong; Nie, Defu; Wu, Qiaoguo

    2018-04-01

    A three-dimensional transient computational fluid dynamics (CFD) model has been established for the simulations of supercritical heat transfer of real liquefied natural gas (LNG) mixture in a single tube and a tube bundle of an intermediate fluid vaporizer (IFV). The influence of chemical composition of LNG on the thermal performance has been analyzed. The results have also been compared with those obtained from the one-dimensional steady-state calculations using the distributed parameter model (DPM). It is found that the current DPM approach can give reasonable prediction accuracy for the thermal performance in the tube bundle but unsatisfactory prediction accuracy for that in a single tube as compared with the corresponding CFD data. As benchmarked against pure methane, the vaporization of an LNG containing about 90% (mole fraction) of methane would lead to an absolute deviation of 5.5 K in the outlet NG temperature and a maximum relative deviation of 11.4% in the tube side HTC in a bundle of about 816 U tubes at the inlet pressure of 12 MPa and mass flux of 200 kg·m-2·s-1. It is concluded that the influence of LNG composition on the thermal performance should be taken into consideration in order to obtain an economic and reliable design of an IFV.

  5. Relationship between non-destructive OCT evaluation of resins composites and bond strength in a cavity

    NASA Astrophysics Data System (ADS)

    Bakhsh, T. A.; Sadr, A.; Shimada, Y.; Khunkar, S.; Tagami, J.; Sumi, Y.

    2012-01-01

    Objectives: Formation of microgaps under the composite restorations due to polymerization stress and other causes compromise the adhesion to the dental substrate and restoration durability. However, the relationship between cavity adaptation and bond strength is not clear. In this paper, we introduce a new testing method to assess cavity adaptation by swept-source optical coherence tomography (SS-OCT) and microtensile bond strength (MTBS) in the same class-I cavity. Methods: Round class-I cavities 3 mm in diameter and 1.5 mm in depth were prepared on 10 human premolars. After application of Tokuyama Bond Force adhesive, the cavities were filled by one of the two techniques; incremental technique using Estelite Sigma Quick universal composite or flowable lining using Palfique Estelite LV with bulk filling using the universal composite. Ten serial B-scan images were obtained throughout each cavity by SS-OCT. Significant peaks in the signal intensity were detected at the bonded interface of the cavity floor and to compare the different filling techniques. The specimens were later cut into beams (0.7x0.7 mm) and tested to measure MTBS at the cavity floor. Results: Flowable lining followed by bulk filling was inferior in terms of cavity adaptation and MTBS compared to the incremental technique (p<0.05, t-test). The adaptation (gap free cavity floor) and MTBS followed similar trends in both groups. Conclusion: Quantitative assessment of dental restorations by OCT can provide additional information on the performance and effectiveness of dental composites and restoration techniques. This study was supported by Global Center of Excellence, Tokyo Medical and Dental University and King Abdulaziz University.

  6. Regolith in the South Pole-Aitken Basin is Mainly Indigenous Material

    NASA Technical Reports Server (NTRS)

    Haskin, L. A.; Gillis, J. J.; Jolliff, B. L.; Korotev, R. L.

    2003-01-01

    This abstract is concerned with the probability that a mission to a site within the South Pole-Aitken basin (SPA) would yield a meaningful sample of typical SPA floor material. The probability seems favorable, barring a highly atypical landing site, because the chemical composition of the SPA interior, as determined remotely from orbit, is different from that of the surrounding lunar surface. How representative would the sample be? To what extent have lateral transport or later events compromised the original chemical and mineralogical composition of the floor material? Where or in what kind of deposit should the mission land to provide the best example? We address these questions from the point of view of modeling of impact ejecta deposits. SPA is the largest lunar impact basin. Shallow for its diameter, it has a subdued gravity signature, a lower albedo, and a more Th- and Ferich interior than the surrounding highlands (the Feldspathic Highlands Terrane, FHT). Its floor may represent noritic or perhaps (but less abundant) gabbroic lower crust of the FHT, the upper crust stripped away by the basin-forming impact, possibly an oblique one.

  7. Fatal Airway Obstruction in a Man With a Cystic Hygroma.

    PubMed

    Wygant, Cassandra Maria; Cohle, Stephen D

    2018-05-03

    We describe a 24-year-old man with a cystic hygroma of the left side of the lower neck that led to sudden death. Cystic hygroma (cystic lymphangioma) is a congenital malformation of the lymphatic system. The patient, who had a tracheostomy because of airway obstruction from the cystic hygroma, was found dead with his tracheostomy tube on the floor next to him. Complications of cystic hygroma include infiltration of the neck causing airway obstruction, dysphagia, pain, and obstructive sleep apnea.

  8. Foundation Design against Frost Action in Europe.

    DTIC Science & Technology

    1988-03-01

    the inside of the foundation wall and consisted of 50mm of ’Rockwool’ (a mineral wool ). This insulation guides heat from the house down toward the...Separation of the floor slab from the inner part of the foundation wall by introducing mineral wool (Fig. 49c) gives a further slight reduction in...construction consisting, for example, of wood and mineral wool and including air spaces. Rt is the thermal resistance of the composite floor from surface to

  9. Finite lateral compression of an elastic plasticfibre-reinforced tube : loading solutions

    NASA Astrophysics Data System (ADS)

    England, A. H.; Gregory, P. W.

    1999-02-01

    This paper considers the finite plane-strain deformations of an elastic-plastic tubecompressed between two rigid smooth parallel plates. The tube is composed of an elastic-plasticfibre-reinforced material in which the fibres lie in planes perpendicular to the axis of the tube andreinforce the tube in the circumferential direction. The composite is assumed to be an idealmaterial which is inextensible in the fibre-direction and is incompressible. The unloading of theelastic-plastic tube will be considered in a subsequent paper.

  10. Strain and dynamic measurements using fiber optic sensors embedded into graphite/epoxy tubes

    NASA Technical Reports Server (NTRS)

    Dehart, D. W.; Doederlein, T.; Koury, J.; Rogowski, R. S.; Heyman, J. S.; Holben, M. S., Jr.

    1989-01-01

    Graphite/epoxy tubes were fabricated with embedded optical fibers to evaluate the feasibility of monitoring strains with a fiber optic technique. Resistance strain gauges were attached to the tubes to measure strain at four locations along the tube for comparison with the fiber optic sensors. Both static and dynamic strain measurements were made with excellent agreement between the embedded fiber optic strain sensor and the strain gauges. Strain measurements of 10(exp -7) can be detected with the optical phase locked loop (OPLL) system using optical fiber. Because of their light weight, compatibility with composites, immunity to electromagnetic interference, and based on the static and dynamic results obtained, fiber optic sensors embedded in composites may be useful as the sensing component of smart structures.

  11. Exposure to potentially toxic hydrocarbons and halocarbons released from the dialyzer and tubing set during hemodialysis.

    PubMed

    Lee, Hyun Ji Julie; Meinardi, Simone; Pahl, Madeleine V; Vaziri, Nostratola D; Blake, Donald R

    2012-10-01

    Although much is known about the effect of chronic kidney failure and dialysis on the composition of solutes in plasma, little is known about their impact on the composition of gaseous compounds in exhaled breath. This study was designed to explore the effect of uremia and the hemodialysis (HD) procedure on the composition of exhaled breath. Breath samples were collected from 10 dialysis patients immediately before, during, and after a dialysis session. To determine the potential introduction of gaseous compounds from dialysis components, gasses emitted from dialyzers, tubing set, dialysate, and water supplies were collected. Prospective cohort study. 10 HD patients and 10 age-matched healthy individuals. Predictors include the dialyzers, tubing set, dialysate, and water supplies before, during, and after dialysis. Changes in the composition of exhaled breath. A 5-column/detector gas chromatography system was used to measure hydrocarbon, halocarbon, oxygenate, and alkyl nitrate compounds. Concentrations of 14 hydrocarbons and halocarbons in patients' breath rapidly increased after the onset of the HD treatment. All 14 compounds and 5 others not found in patients' breath were emitted from the dialyzers and tubing sets. Contrary to earlier reports, exhaled breath ethane concentrations in our dialysis patients were virtually unchanged during the HD treatment. Single-center study with a small sample size may limit the generalizability of the findings. The study documented the release of several potentially toxic hydrocarbons and halocarbons to patients from the dialyzer and tubing sets during the HD procedure. Because long-term exposure to these compounds may contribute to the morbidity and mortality in dialysis population, this issue should be considered in the manufacturing of the new generation of dialyzers and dialysis tubing sets. Copyright © 2012 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

  12. Fermented Papaya Preparation Restores Age-Related Reductions in Peripheral Blood Mononuclear Cell Cytolytic Activity in Tube-Fed Patients

    PubMed Central

    Fujita, Yuhzo; Tsuno, Haruo; Nakayama, Jiro

    2017-01-01

    Tube-fed elderly patients are generally supplied with the same type of nutrition over long periods, resulting in an increased risk for micronutrient deficiencies. Dietary polyphenols promote immunity and have anti-inflammatory, anti-carcinogenic, and anti-oxidative properties. Carica papaya Linn. is rich in several polyphenols; however, these polyphenols are poorly absorbed from the digestive tract in their original polymerized form. Therefore, we determined the molecular components of a fermented Carica papaya Linn. preparation, as well as its effects on immunity and the composition of gut microbiota in tube-fed patients. Different doses of the fermented C. papaya L. preparation were administered to three groups of tube-fed patients for 30 days. Its effects on fecal microbiota composition and immunity were assessed by 16S rRNA gene sequencing and immune-marker analysis, respectively. The chemical composition of the fermented C. papaya L. preparation was analyzed by capillary electrophoresis- and liquid chromatography- time of flight mass spectrometry. The fermented C. papaya L. preparation restored peripheral blood mononuclear cell (PBMC) cytolytic activity; however, no other biomarkers of immunity were observed. Treatment with the preparation (9 g/day) significantly reduced the abundance of Firmicutes in the fecal microbiota. In particular, treatment reduced Clostridium scindens and Eggerthella lenta in most patients receiving 9 g/day. Chemical analysis identified low-molecular-weight phenolic acids as polyphenol metabolites; however, no polymerized, large-molecular-weight molecules were detected. Our study indicates that elderly patients who are tube-fed over the long-term have decreased PBMC cytolytic activity. In addition, low-molecular-weight polyphenol metabolites fermented from polymerized polyphenols restore PBMC cytolytic activity and modulate the composition of gut microbiota in tube-fed patients. PMID:28060858

  13. The axial crushes behaviour on foam-filled round Jute/Polyester composite tubes

    NASA Astrophysics Data System (ADS)

    Othman, A.; Ismail, A. E.

    2018-04-01

    The present paper investigates the effect of axial loading compression on jute fibre reinforced polyester composite round tubes. The specimen of composite tube was fabricated by hand lay-up method of 120 mm length with fix 50.8 mm inner diameter to determine the behaviour of energy absorption on number of layers of 450 angle fibre and internally reinforced with and without foam filler material. The foam filler material used in this studies were polyurethane (PU) and polystyrene (PE) with average of 40 and 45 kg/m3 densities on the axial crushing load against displacement relations and on the failure modes. The number of layers of on this study were two; three and four were selected to calculate the crush force efficiency (CFE) and the specific energy absorption (SEA) of the composite tubes. Result indicated that the four layers’ jute/polyester show significant value in term of crushing load compared to 2 and 3 layers higher 60% for 2 layer and 3% compared to 3 layers. It has been found that the specific energy absorption of the jute/polyester tubes with polystyrene foam-filled is found higher respectively 10% to 12% than empty and polyurethane (PU) foam tubes. The increase in the number of layers from two to four increases the mean axial load from 1.01 KN to 3.60 KN for empty jute/polyester and from 2.11 KN to 4.26 KN for the polyurethane (PU) foam-filled jute/polyester tubes as well as for 3.60 KN to 5.58 KN for the polystyrene (PE) foam-filled jute/polyester. The author’s found that the failure of mechanism influence the characteristic of curve load against displacement obtained and conclude that an increasing number of layers and introduce filler material enhance the capability of specific absorbed energy.

  14. Combining Through-Thickness Reinforcement and Self-Healing for Improved Damage Tolerance and Durability of Composites

    NASA Technical Reports Server (NTRS)

    O'Brien, T. Kevin; Czabaj, Michael W.; Hinkley, Jeffrey A.; Tsampas, Spiros; Greenhalgh, Emile S.; McCombe, Gregory; Bond, Ian P.; Trask, Richard

    2013-01-01

    A study was undertaken to develop a prototype method for adding through-thickness hollow glass tubes infused with uncured resin and hardener in a carbon Z-pin through-thickness reinforcement field embedded in a composite laminate. Two types of tube insertion techniques were attempted in an effort to ensure the glass tubes survived the panel manufacturing process. A self-healing resin was chosen with a very low viscosity, two component, liquid epoxy resin system designed to be mixed at a 2-to-1 ratio of epoxy to hardener. IM7/8552 carbon epoxy double cantilever beam (DCB) specimens were cut from the hybrid Z-pin and glass tube reinforced panels and tested. In-situ injection of resin and hardener directly into glass tubes, in a staggered pattern to allow for 2-to-1 ratio mixing, resulted in partial healing of the fracture plane, but only if the injection was performed while the specimen was held at maximum load after initial fracture. Hence, there is some potential for healing delamination via resin and hardener delivered through a network of through-thickness glass tubes, but only if the tubes are connected to a reservoir where additional material may be injected as needed.

  15. Chemical speciation of size-segregated floor dusts and airborne magnetic particles collected at underground subway stations in Seoul, Korea.

    PubMed

    Jung, Hae-Jin; Kim, BoWha; Malek, Md Abdul; Koo, Yong Sung; Jung, Jong Hoon; Son, Youn-Suk; Kim, Jo-Chun; Kim, HyeKyoung; Ro, Chul-Un

    2012-04-30

    Previous studies have reported the major chemical species of underground subway particles to be Fe-containing species that are generated from wear and friction processes at rail-wheel-brake and catenaries-pantographs interfaces. To examine chemical composition of Fe-containing particles in more details, floor dusts were collected at five sampling locations of an underground subway station. Size-segregated floor dusts were separated into magnetic and non-magnetic fractions using a permanent magnet. Using X-ray diffraction (XRD) and scanning electron microscopy/energy dispersive X-ray spectrometry (SEM/EDX), iron metal, which is relatively harmless, was found to be the dominating chemical species in the floor dusts of the <25 μm size fractions with minor fractions of Mg, Al, Si, Ca, S, and C. From SEM analysis, the floor dusts of the <25 μm size fractions collected on railroad ties appeared to be smaller than 10 μm, indicating that their characteristics should somewhat reflect the characteristics of airborne particles in the tunnel and the platform. As most floor dusts are magnetic, PM levels at underground subway stations can be controlled by removing magnetic indoor particles using magnets. In addition, airborne subway particles, most of which were smaller than 10 μm, were collected using permanent magnets at two underground subway stations, namely Jegi and Yangjae stations, in Seoul, Korea. XRD and SEM/EDX analyses showed that most of the magnetic aerosol particles collected at Jegi station was iron metal, whereas those at Yangjae station contained a small amount of Fe mixed with Na, Mg, Al, Si, S, Ca, and C. The difference in composition of the Fe-containing particles between the two subway stations was attributed to the different ballast tracks used. Copyright © 2012 Elsevier B.V. All rights reserved.

  16. Properties of dissolved and total organic matter in throughfall, stemflow and forest floor leachate of Central European forests

    NASA Astrophysics Data System (ADS)

    Bischoff, S.; Schwarz, M. T.; Siemens, J.; Thieme, L.; Wilcke, W.; Michalzik, B.

    2014-10-01

    For the first time, we investigated the composition of dissolved organic matter (DOM) compared to total OM (TOM, consisting of DOM and particulate OM, POM) in throughfall, stemflow and forest floor leachate of beech and spruce forests using solid state 13C nuclear magnetic resonance spectroscopy. We hypothesized that the composition and properties of OM in forest ecosystem water samples differed between DOM and TOM and between the two tree species. Under beech, a contribution of phyllosphere-derived fresh POM was echoed in structural differences. Compared with DOM, TOM exhibited higher relative intensities for the alkyl C region, representing aliphatic C from less decomposed organic material, and lower relative intensities for lignin-derived and aromatic C of the aryl C region, resulting in lower aromaticity indices and reduced humification intensities. Since differences in the structural composition of DOM and TOM were less pronounced under spruce than under beech, we suspect a~tree species-related effect on the origin of OM composition and resulting properties (e.g. recalcitrance, allelopathic potential).

  17. Astrobiology Training in Lava Tubes (ATiLT): Characterizing coralloid speleothems in basaltic lava tubes as a Mars analogue

    NASA Astrophysics Data System (ADS)

    Ni, J.; Leveille, R. J.; Douglas, P.

    2017-12-01

    Coralloid speleothems or cave corals are small mineralised nodes that can take a variety of forms, and which develop through groundwater seepage and water-rock interaction in caves. They are found commonly on Earth in a plethora of caves, including lava tubes. Since lava tubes have been identified on the surface of Mars from remotely sensed images, there has been interest in studying Earth's lava tube systems as an analogue for understanding Martian lava environments. If cave minerals were found on Mars, they could indicate past or present water-rock interaction in the Martian subsurface. Martian lava tubes could also provide insights into habitable subsurface environments as well as conditions favourable for the synthesis and preservation of biosignatures. One of the aims of the Astrobiology Training in Lava Tubes (ATiLT) project is to analyze biosignatures and paleoenvironmental indicators in secondary cave minerals, which will be looked at in-situ and compared to collected field samples. In this study, secondary mineralization in lava cave systems from Lava Beds National Monument, CA is examined. In the field, coralloid speleothems have been observed growing on all surfaces of the caves, including cave ceilings, floors, walls and overhangs. They are also observed growing adjacent to biofilms, which sometimes fill in the cracks of the coralloid nodes. Preliminary results show the presence of opal, calcite, quartz and other minor minerals in the speleothems. This study seeks to understand the formation mechanism and source of these secondary minerals, as well as determine their possible relation to the biofilms. This will be done through the analysis of the water chemistry, isotope geochemistry and microscale mineralogy.

  18. The impact of a chest tube management protocol on the outcome of trauma patients with tube thoracostomy.

    PubMed

    de Abreu, Emanuelle Maria Sávio; Machado, Carla Jorge; Pastore Neto, Mario; de Rezende Neto, João Baptista; Sanches, Marcelo Dias

    2015-01-01

    to investigate the effect of standardized interventions in the management of tube thoracostomy patients and to assess the independent effect of each intervention. A chest tube management protocol was assessed in a retrospective cohort study. The tube thoracostomy protocol (TTP) was implemented in August 2012, and consisted of: antimicrobial prophylaxis, chest tube insertion in the operating room (OR), admission post chest tube thoracostomy (CTT) in a hospital floor separate from the emergency department (ED), and daily respiratory therapy (RT) sessions post-CTT. The inclusion criteria were, hemodynamic stability, patients between the ages of 15 and 59 years, and injury severity score (ISS) < 17. All patients had isolated injuries to the chest wall, lung, and pleura. During the study period 92 patients were managed according to the standardized protocol. The outcomes of those patients were compared to 99 patients treated before the TTP. Multivariate logistic regression analysis was performed to assess the independent effect of each variable of the protocol on selected outcomes. Demographics, injury severity, and trauma mechanisms were similar among the groups. As expected, protocol compliance increased after the implementation of the TTP. There was a significant reduction (p<0.05) in the incidence of retained hemothoraces, empyemas, pneumonias, surgical site infections, post-procedural complications, hospital length of stay, and number of chest tube days. Respiratory therapy was independently linked to significant reduction (p<0.05) in the incidence of seven out of eight undesired outcomes after CTT. Antimicrobial prophylaxis was linked to a significant decrease (p<0.05) in retained hemothoraces, despite no significant (p<0.10) reductions in empyema and surgical site infections. Conversely, OR chest tube insertion was associated with significant (p<0.05) reduction of both complications, and also significantly decreased the incidence of pneumonias. Implementation of a TTP effectively reduced complications after CTT in trauma patients.

  19. FRACTURE STRENGTH AND TIME DEPENDENT PROPERTIES OF 0/90 AND ±55-BRAIDED WEAVE SiC/SiC TYPE-S FIBER COMPOSITES

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Henager, Charles H.

    PNNL has performed mechanical property tests on two types of Hi-Nicalon Type-S fiber SiC/SiC composites for the general purpose of evaluating such composites for control rod guide tube applications in the NGNP high-temperature gas-cooled reactor design. The mechanical testing consisted of 4-point bend strength, 4-point single-edge notched bend fracture toughness, and 4-point bend slow crack growth testing on both composites from ambient to 1600°C (1873K). The two composite materials that were tested included a ±55°-braided-weave composite with Type-S fibers inclined at 55° to the principal composite axes to simulate a braided tube architecture and a Type-S 0/90 satin-weave composite asmore » a reference material.« less

  20. Low thermal flux glass-fiber tubing for cryogenic service.

    NASA Technical Reports Server (NTRS)

    Hall, C. A.; Pharo, T. J., Jr.; Phillips, J. M.

    1972-01-01

    Study of thin metallic liners which provide leak-free service in cryogenic propulsion plumbing systems and are overwrapped with a glass-fiber composite that provides strength and protection from handling damage. The composite tube is lightweight, strong, and has a very low thermal flux. The resultant reduced boiloff of stored cryogenic propellants yields a substantial weight savings for long-term missions (seven days or greater). Twelve styles of tubing ranging from 1/2 to 5 in. in diameter were fabricated and tested with excellent results for most of the concepts at operating temperatures from +70 to -423 F and operating pressures up to 3000 psi.

  1. Quartz antenna with hollow conductor

    DOEpatents

    Leung, Ka-Ngo; Benabou, Elie

    2002-01-01

    A radio frequency (RF) antenna for plasma ion sources is formed of a hollow metal conductor tube disposed within a glass tube. The hollow metal tubular conductor has an internal flow channel so that there will be no coolant leakage if the outer glass tube of the antenna breaks. A portion of the RF antenna is formed into a coil; the antenna is used for inductively coupling RF power to a plasma in an ion source chamber. The antenna is made by first inserting the metal tube inside the glass tube, and then forming the glass/metal composite tube into the desired coil shape.

  2. Soft Plumbing: Direct-Writing and Controllable Perfusion of Tubular Soft Materials

    NASA Astrophysics Data System (ADS)

    Guenther, Axel; Omoruwa, Patricia; Chen, Haotian; McAllister, Arianna; Jeronimo, Mark; Malladi, Shashi; Hakimi, Navid; Cao, Li; Ramchandran, Arun

    2016-11-01

    Tubular and ductular structures are abundant in tissues in a wide variety of diameters, wall thicknesses, and compositions. In spite of their relevance to engineered tissues, organs-on-chips and soft robotics, the rapid and consistent preparation of tubular structures remains a challenge. Here, we use a microfabricated printhead to direct-write biopolymeric tubes with dimensional and compositional control. A biopolymer solution is introduced to the center layer of the printhead, and the confining fluids to the top and the bottom layers. The radially flowing biopolymer solution is sandwiched between confining solutions that initiate gelation, initially assuming the shape of a funnel until emerging through a cylindrical confinement as a continuous biopolymer tube. Tubular constructs of sodium alginate and collagen I were obtained with inner diameters (0.6-2.2mm) and wall thicknesses (0.1-0.4mm) in favorable agreement with predictions of analytical models. We obtained homogeneous tubes with smooth and buckled walls and heterotypic constructs that possessed compositions that vary along the tube circumference or radius. Ductular soft materials were reversibly hosted in 3D printed fluidic devices for the perfusion at well-defined transmural pressures to explore the rich variety of dynamical features associated with collapsible tubes that include buckling, complete collapse, and self-oscillation.

  3. Compositional studies of Mare Moscoviense: New perspectives from Chandrayaan-1 VIS-NIR data

    NASA Astrophysics Data System (ADS)

    Bhatt, Megha; Wöhler, Christian; Dhingra, Deepak; Thangjam, Guneshwar; Rommel, Daniela; Mall, Urs; Bhardwaj, Anil; Grumpe, Arne

    2018-03-01

    Moscoviense is one of the prominent mare-filled basin on the lunar far side holding key insights about volcanic activity on the far side. Here, we present spectral and elemental maps of mare Moscoviense, using the Moon Mineralogy Mapper (M3) and Infrared Spectrometer-2 (SIR-2) data-sets. The different mare units are mapped based on their spectral properties analyzing both quantitatively (band center, band depth) and qualitatively (Integrated Band Depth composite images), and also using their elemental compositions. We find a total of five distinct spectral units from the basin floor based on the spectral properties. Our analysis suggests that the northern part which was mapped as Iltm unit (Imbrian low Ti, low Fe) by earlier researchers is actually a distinct unit, which is different in composition and age, named as Ivltm unit (Imbrian very low Ti and very low Fe). We obtain the absolute model age of 3.2 Ga with uncertainties of +0.2/ -0.5 Ga for the unit Ivltm. The newly identified basalt unit Ivltm is compositionally intermediate to the units Im and Iltm in FeO and TiO2 abundances. We find a total of five distinct spectral units from the basin floor based on the spectral properties. The units Im (Imbrian very low Ti) from southern and northern regions of the basin floor are spectrally distinct in terms of band center position and corresponding band depths but considered a single unit based on the elemental abundance analysis. The units Ivltm and Im are consistent with a high-Al basalt composition. Our detailed analysis of the entire Moscoviense basin indicates that the concentrations of orthopyroxene, olivine, and Mg-rich spinel, named as OOS rock family are widespread and dominant at the western and southern side of the middle ring of the basin with one isolated area found on the northern side of the peak ring.

  4. The Bond Strength of Composite Resin to Dental Casting Alloys Using an Electro-Chemical Tin Plating System.

    DTIC Science & Technology

    1985-06-01

    of Opaque-Adhesive Containing Opaque Powder ..................... 36 Figure 12. Isosit Resin Condensed into Teflon Tubes ..... 37 Figure 13. Device...millimeter long teflon tube was positioned centrally on each specimen. The Isosit body resin was condensed into the tube using the blunt end of a...8217.*. .’-~ ~**.*~.**.**.*~.**.*%~ 37 Figure 12. Isosit Resin Condensed into Teflon Tubes Wy~WW’. WVtTh. .. . - . - S.. * ***’h.).’ *.~’b

  5. Sea-floor character and sedimentary processes of Block Island Sound, offshore Rhode Island

    USGS Publications Warehouse

    Poppe, L.J.; Danforth, W.W.; McMullen, K.Y.; Blankenship, M.A.; Glomb, K.A.; Wright, D.B.; Smith, S.M.

    2012-01-01

    Gridded multibeam bathymetry covers approximately 634 square kilometers of sea floor in Block Island Sound. Although originally collected for charting purposes during National Oceanic and Atmospheric Administration hydrographic surveys H12009, H12010, H12011, H12015, H12033, H12137, and H12139, these combined acoustic data and the sea-floor sediment sampling and photography stations subsequently occupied to verify them during U.S. Geological Survey cruise 2011-006-FA (1) show the composition and terrain of the seabed, (2) provide information on sediment transport and benthic habitat, and (3) are part of an expanding series of studies that provide a fundamental framework for research and management activities (for example, wind farms and fisheries) along the Rhode Island inner continental shelf.

  6. Conduit for high temperature transfer of molten semiconductor crystalline material

    NASA Technical Reports Server (NTRS)

    Fiegl, George (Inventor); Torbet, Walter (Inventor)

    1983-01-01

    A conduit for high temperature transfer of molten semiconductor crystalline material consists of a composite structure incorporating a quartz transfer tube as the innermost member, with an outer thermally insulating layer designed to serve the dual purposes of minimizing heat losses from the quartz tube and maintaining mechanical strength and rigidity of the conduit at the elevated temperatures encountered. The composite structure ensures that the molten semiconductor material only comes in contact with a material (quartz) with which it is compatible, while the outer layer structure reinforces the quartz tube, which becomes somewhat soft at molten semiconductor temperatures. To further aid in preventing cooling of the molten semiconductor, a distributed, electric resistance heater is in contact with the surface of the quartz tube over most of its length. The quartz tube has short end portions which extend through the surface of the semiconductor melt and which are lef bare of the thermal insulation. The heater is designed to provide an increased heat input per unit area in the region adjacent these end portions.

  7. Surface sampling concentration and reaction probe

    DOEpatents

    Van Berkel, Gary J; Elnaggar, Mariam S

    2013-07-16

    A method of analyzing a chemical composition of a specimen is described. The method can include providing a probe comprising an outer capillary tube and an inner capillary tube disposed co-axially within the outer capillary tube, where the inner and outer capillary tubes define a solvent capillary and a sampling capillary in fluid communication with one another at a distal end of the probe; contacting a target site on a surface of a specimen with a solvent in fluid communication with the probe; maintaining a plug volume proximate a solvent-specimen interface, wherein the plug volume is in fluid communication with the probe; draining plug sampling fluid from the plug volume through the sampling capillary; and analyzing a chemical composition of the plug sampling fluid with an analytical instrument. A system for performing the method is also described.

  8. Surface sampling concentration and reaction probe with controller to adjust sampling position

    DOEpatents

    Van Berkel, Gary J.; ElNaggar, Mariam S.

    2016-07-19

    A method of analyzing a chemical composition of a specimen is described. The method can include providing a probe comprising an outer capillary tube and an inner capillary tube disposed co-axially within the outer capillary tube, where the inner and outer capillary tubes define a solvent capillary and a sampling capillary in fluid communication with one another at a distal end of the probe; contacting a target site on a surface of a specimen with a solvent in fluid communication with the probe; maintaining a plug volume proximate a solvent-specimen interface, wherein the plug volume is in fluid communication with the probe; draining plug sampling fluid from the plug volume through the sampling capillary; and analyzing a chemical composition of the plug sampling fluid with an analytical instrument. A system for performing the method is also described.

  9. Floor-Fractured Craters on Ceres and Implications for Internal Composition and Processes

    NASA Astrophysics Data System (ADS)

    Buczkowski, D.; Schenk, P.; Scully, J. E. C.; Park, R. S.; Preusker, F.; Raymond, C. A.; Russell, C. T.

    2016-12-01

    Several of the impact craters on Ceres have patterns of fractures on their floors. These fractures appear similar to those found within a class of lunar craters referred to as Floor-Fractured Craters (FFCs) [1]. Lunar FFCs are characterized by anomalously shallow floors cut by radial, concentric, and/or polygonal fractures, and have been classified into crater classes, Types 1 through 6, based on their morphometric properties [1,2]. Models for their formation have included both floor uplift due to magmatic intrusion below the crater or floor shallowing due to viscous relaxation. However, the observation that the depth versus diameter (d/D) relationship of the FFCs is distinctly shallower than the same association for other lunar craters supports the hypotheses that the floor fractures form due to shallow magmatic intrusion under the crater [2]. We have cataloged the Ceres FFCs according to the classification scheme designed for the Moon. Large (>50 km) Ceres FFCs are most consistent with Type 1 lunar FFCs, having deep floors, central peaks, wall terraces, and radial and/or concentric fractures. Smaller craters on Ceres are more consistent with Type 4 lunar FFCs, having less-pronounced floor fractures and v-shaped moats separating the wall scarp from the crater interior. An analysis of the d/D ratio for Ceres craters shows that, like lunar FFCs, the Ceres FFCs are anomalously shallow. This suggests that the fractures on the floor of Ceres FFCs may be due the intrusion of a low-density material below the craters that is uplifting their floors. While on the Moon the intrusive material is hypothesized to be silicate magma, this is unlikely for Ceres. However, a cryovolcanic extrusive edifice has been identified on Ceres [3], suggesting that cryomagmatic intrusions could be responsible for the formation of the Ceres FFCs. References: [1] Schultz P. (1976) Moon, 15, 241-273 [2] Jozwiak L.M. et al (2015) JGR 117, doi: 10.1029/2012JE004134 [3] Ruesch O. et al (2016) Science

  10. Oceanic Basement Probed

    ERIC Educational Resources Information Center

    Cann, J. R.; Moore, David G.

    1978-01-01

    Summarizes findings of the deep sea drilling project at Scripps Institute of Oceanology. Results of Atlantic and Pacific Ocean drillings in terms of the composition and properties of the sea floor are discussed. (CP)

  11. Template synthesis of test tube nanoparticles using non-destructive replication

    PubMed Central

    Wagner, Jonathan; Yao, Jingyuan; Rodgers, David; Hinds, Bruce

    2013-01-01

    Nano test tubes are a promising delivery vehicle for a range of therapeutics including small molecule drugs and biologics. However, current template synthesis methods of producing nano test tubes are prohibitively expensive and time consuming. Here, non-destructive template replication was used to increase nano test tube yield from porous alumina by more than a hundredfold. We demonstrate how to produce nano test tubes of several sizes and compositions including hybrid tubes with different inner and outer surfaces for targeted surface chemistry. Nano test tubes were readily suspended and stored in aqueous solutions without the need for chemical treatment. These nano test tubes should find application as delivery vehicles for therapeutics, particularly for processive “bionanoreactors” loaded with enzymes. PMID:23376956

  12. Inelastic response of metal matrix composites under biaxial loading

    NASA Technical Reports Server (NTRS)

    Mirzadeh, F.; Pindera, Marek-Jerzy; Herakovich, Carl T.

    1990-01-01

    Elements of the analytical/experimental program to characterize the response of silicon carbide titanium (SCS-6/Ti-15-3) composite tubes under biaxial loading are outlined. The analytical program comprises prediction of initial yielding and subsequent inelastic response of unidirectional and angle-ply silicon carbide titanium tubes using a combined micromechanics approach and laminate analysis. The micromechanics approach is based on the method of cells model and has the capability of generating the effective thermomechanical response of metal matrix composites in the linear and inelastic region in the presence of temperature and time-dependent properties of the individual constituents and imperfect bonding on the initial yield surfaces and inelastic response of (0) and (+ or - 45)sub s SCS-6/Ti-15-3 laminates loaded by different combinations of stresses. The generated analytical predictions will be compared with the experimental results. The experimental program comprises generation of initial yield surfaces, subsequent stress-strain curves and determination of failure loads of the SCS-6/Ti-15-3 tubes under selected loading conditions. The results of the analytical investigation are employed to define the actual loading paths for the experimental program. A brief overview of the experimental methodology is given. This includes the test capabilities of the Composite Mechanics Laboratory at the University of Virginia, the SCS-6/Ti-15-3 composite tubes secured from McDonnell Douglas Corporation, a text fixture specifically developed for combined axial-torsional loading, and the MTS combined axial-torsion loader that will be employed in the actual testing.

  13. Vineyard floor management and cluster thinning inconsistently affect ‘Pinot noir’ crop load, berry composition, and wine quality

    USDA-ARS?s Scientific Manuscript database

    A 3-year field study was developed to determine relationships between crop load metrics and berry composition for ‘Pinot noir’ in a cool-climate through the manipulation of vegetative growth and fruit yield using competitive cover cropping and cluster thinning, respectively. To alter vine vigor, per...

  14. Fast Reacting Nano Composite Energetic Materials: Synthesis and Combustion Characterization

    DTIC Science & Technology

    2015-08-24

    mg of composite resulting in a loose powder fill estimated to be 7% of the theoretical maximum density. Once prepared, the tube was placed in a steel ...theoretical maximum density. Once prepared, the tube was placed in a steel combustion chamber and the experimental setup is schematically represented... Valery Levitas. "Effect of oxide shell growth on ano- aluminum thermite propagation rates." Combustion and Flame 159 (2012): 3448-3453. I. Liakosa

  15. STATISTICAL ANALYSIS OF TANK 5 FLOOR SAMPLE RESULTS

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shine, E.

    2012-03-14

    Sampling has been completed for the characterization of the residual material on the floor of Tank 5 in the F-Area Tank Farm at the Savannah River Site (SRS), near Aiken, SC. The sampling was performed by Savannah River Remediation (SRR) LLC using a stratified random sampling plan with volume-proportional compositing. The plan consisted of partitioning the residual material on the floor of Tank 5 into three non-overlapping strata: two strata enclosed accumulations, and a third stratum consisted of a thin layer of material outside the regions of the two accumulations. Each of three composite samples was constructed from five primarymore » sample locations of residual material on the floor of Tank 5. Three of the primary samples were obtained from the stratum containing the thin layer of material, and one primary sample was obtained from each of the two strata containing an accumulation. This report documents the statistical analyses of the analytical results for the composite samples. The objective of the analysis is to determine the mean concentrations and upper 95% confidence (UCL95) bounds for the mean concentrations for a set of analytes in the tank residuals. The statistical procedures employed in the analyses were consistent with the Environmental Protection Agency (EPA) technical guidance by Singh and others [2010]. Savannah River National Laboratory (SRNL) measured the sample bulk density, nonvolatile beta, gross alpha, radionuclide, inorganic, and anion concentrations three times for each of the composite samples. The analyte concentration data were partitioned into three separate groups for further analysis: analytes with every measurement above their minimum detectable concentrations (MDCs), analytes with no measurements above their MDCs, and analytes with a mixture of some measurement results above and below their MDCs. The means, standard deviations, and UCL95s were computed for the analytes in the two groups that had at least some measurements above their MDCs. The identification of distributions and the selection of UCL95 procedures generally followed the protocol in Singh, Armbya, and Singh [2010]. When all of an analyte's measurements lie below their MDCs, only a summary of the MDCs can be provided. The measurement results reported by SRNL are listed in Appendix A, and the results of this analysis are reported in Appendix B. The data were generally found to follow a normal distribution, and to be homogeneous across composite samples.« less

  16. Statistical Analysis of Tank 5 Floor Sample Results

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shine, E. P.

    2013-01-31

    Sampling has been completed for the characterization of the residual material on the floor of Tank 5 in the F-Area Tank Farm at the Savannah River Site (SRS), near Aiken, SC. The sampling was performed by Savannah River Remediation (SRR) LLC using a stratified random sampling plan with volume-proportional compositing. The plan consisted of partitioning the residual material on the floor of Tank 5 into three non-overlapping strata: two strata enclosed accumulations, and a third stratum consisted of a thin layer of material outside the regions of the two accumulations. Each of three composite samples was constructed from five primarymore » sample locations of residual material on the floor of Tank 5. Three of the primary samples were obtained from the stratum containing the thin layer of material, and one primary sample was obtained from each of the two strata containing an accumulation. This report documents the statistical analyses of the analytical results for the composite samples. The objective of the analysis is to determine the mean concentrations and upper 95% confidence (UCL95) bounds for the mean concentrations for a set of analytes in the tank residuals. The statistical procedures employed in the analyses were consistent with the Environmental Protection Agency (EPA) technical guidance by Singh and others [2010]. Savannah River National Laboratory (SRNL) measured the sample bulk density, nonvolatile beta, gross alpha, and the radionuclide1, elemental, and chemical concentrations three times for each of the composite samples. The analyte concentration data were partitioned into three separate groups for further analysis: analytes with every measurement above their minimum detectable concentrations (MDCs), analytes with no measurements above their MDCs, and analytes with a mixture of some measurement results above and below their MDCs. The means, standard deviations, and UCL95s were computed for the analytes in the two groups that had at least some measurements above their MDCs. The identification of distributions and the selection of UCL95 procedures generally followed the protocol in Singh, Armbya, and Singh [2010]. When all of an analyte's measurements lie below their MDCs, only a summary of the MDCs can be provided. The measurement results reported by SRNL are listed, and the results of this analysis are reported. The data were generally found to follow a normal distribution, and to be homogenous across composite samples.« less

  17. Statistical Analysis Of Tank 5 Floor Sample Results

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shine, E. P.

    2012-08-01

    Sampling has been completed for the characterization of the residual material on the floor of Tank 5 in the F-Area Tank Farm at the Savannah River Site (SRS), near Aiken, SC. The sampling was performed by Savannah River Remediation (SRR) LLC using a stratified random sampling plan with volume-proportional compositing. The plan consisted of partitioning the residual material on the floor of Tank 5 into three non-overlapping strata: two strata enclosed accumulations, and a third stratum consisted of a thin layer of material outside the regions of the two accumulations. Each of three composite samples was constructed from five primarymore » sample locations of residual material on the floor of Tank 5. Three of the primary samples were obtained from the stratum containing the thin layer of material, and one primary sample was obtained from each of the two strata containing an accumulation. This report documents the statistical analyses of the analytical results for the composite samples. The objective of the analysis is to determine the mean concentrations and upper 95% confidence (UCL95) bounds for the mean concentrations for a set of analytes in the tank residuals. The statistical procedures employed in the analyses were consistent with the Environmental Protection Agency (EPA) technical guidance by Singh and others [2010]. Savannah River National Laboratory (SRNL) measured the sample bulk density, nonvolatile beta, gross alpha, and the radionuclide, elemental, and chemical concentrations three times for each of the composite samples. The analyte concentration data were partitioned into three separate groups for further analysis: analytes with every measurement above their minimum detectable concentrations (MDCs), analytes with no measurements above their MDCs, and analytes with a mixture of some measurement results above and below their MDCs. The means, standard deviations, and UCL95s were computed for the analytes in the two groups that had at least some measurements above their MDCs. The identification of distributions and the selection of UCL95 procedures generally followed the protocol in Singh, Armbya, and Singh [2010]. When all of an analyte's measurements lie below their MDCs, only a summary of the MDCs can be provided. The measurement results reported by SRNL are listed in Appendix A, and the results of this analysis are reported in Appendix B. The data were generally found to follow a normal distribution, and to be homogenous across composite samples.« less

  18. Combustion of Micro- and Nanothermites under Elevating Pressure

    NASA Astrophysics Data System (ADS)

    Monogarov, K.; Pivkina, Alla; Muravyev, N.; Meerov, D.; Dilhan, D.

    Non-equilibrium process of combustion-wave propagation of thermite compositions (Mg/Fe2O3) inside the sealed steel tube have been investigated to study the burning rate at elevating pressure. Under confinement the hot gas-phase products, formed during thermite combustion result in considerable overpressure inside the tube that reverses the gas flow and leads to pressure-driven preheating effect of the burned-gas permeation. Convective origin of this preheating effect is discussed. The pressure-time dependency is obtained experimentally. The composition was pressed inside the steel tube in pellets; the size of each part was measured to obtain burning rate - pressure dependency. Both micro- and nanosized components were used to prepare thermite compositions under study. The significant difference in burning parameters of micron- and nanosized thermites is observed and analyzed. Based on obtained results, the combustion mechanism of thermites with the micro- and nanosized components is discussed.

  19. Burst Testing of Triaxial Braided Composite Tubes

    NASA Technical Reports Server (NTRS)

    Salem, J. A.; Bail, J. L.; Wilmoth, N. G.; Ghosn, L. J.; Kohlman, L. W.; Roberts, G. D.; Martin, R. E.

    2014-01-01

    Applications using triaxial braided composites are limited by the materials transverse strength which is determined by the delamination capacity of unconstrained, free-edge tows. However, structural applications such as cylindrical tubes can be designed to minimize free edge effects and thus the strength with and without edge stresses is relevant to the design process. The transverse strength of triaxial braided composites without edge effects was determined by internally pressurizing tubes. In the absence of edge effects, the axial and transverse strength were comparable. In addition, notched specimens, which minimize the effect of unconstrained tow ends, were tested in a variety of geometries. Although the commonly tested notch geometries exhibited similar axial and transverse net section failure strength, significant dependence on notch configuration was observed. In the absence of unconstrained tows, failure ensues as a result of bias tow rotation, splitting, and fracture at cross-over regions.

  20. Molecular Analysis of Tube Cement of the Biofouling Tubeworm Hydroides elegans

    DTIC Science & Technology

    2016-03-08

    fouler that secretes a tube and strong cement. Little is known about the composition of either of these structures or the genes encoding them. We...the tubeworms cannot attach or can attach only weakly. Cements of H. elegans are secreted during two separate stages of metamorphosis and growth. The...first cements are secreted from the post-trochal region of settling larvae and is a component of a proteinaceous primary tube. This sticky tube is

  1. PCL-PGLA composite tubular scaffold preparation and biocompatibility investigation.

    PubMed

    Mo, X; Weber, H-J; Ramakrishna, S

    2006-08-01

    The objective of this paper was to fabricate a biodegradable tubular scaffold for small diameter (d<6 mm) blood vessel tissue engineering. The tube scaffold needed a porous wall for cell attachment, proliferation and tissue regeneration with its degradation. A novel method given in this paper was to coat a porous layer of poly (epsilon-caprolactone) (PCL) on the outside of a poly (glycolic-co-lactic acid) (PGLA with GA:LA=90:10) fiber braided tube to give a PCL-PGLA composite. The PGLA tube was fabricated using a braiding machine by inserting a Teflon tube with the desired diameter in center of the 20 spindles, which are the carriers of PGLA fibers. Changing the diameter of the Teflon tube can vary the inner diameter of a braided PGLA tube. Thermally induced phase separation method was used for PCL solution coating on the surface of the PGLA braided tube. Controlling the polymer concentration, non-solvent addition and quenching temperature generated the pore structures, with pore sizes ranging from 10-30 microm. The fibroblast cells were seeded on the tubular scaffold and cultured in vitro for the biocompatibility investigation. Histology results showed that the fibroblast cells proliferated on the interconnected pore of the PCL porous layer in 1 week.

  2. Planar Reflection of Detonations Waves

    NASA Astrophysics Data System (ADS)

    Damazo, Jason; Shepherd, Joseph

    2012-11-01

    An experimental study examining normally reflected gaseous detonation waves is undertaken so that the physics of reflected detonations may be understood. Focused schlieren visualization is used to describe the boundary layer development behind the incident detonation wave and the nature of the reflected shock wave. Reflected shock wave bifurcation-which has received extensive study as it pertains to shock tube performance-is predicted by classical bifurcation theory, but is not observed in the present study for undiluted hydrogen-oxygen and ethylene-oxygen detonation waves. Pressure and thermocouple gauges are installed in the floor of the detonation tube so as to examine both the wall pressure and heat flux. From the pressure results, we observe an inconsistency between the measured reflected shock speed and the measured reflected shock strength with one dimensional flow predictions confirming earlier experiments performed in our laboratory. This research is sponsored by the DHS through the University of Rhode Island, Center of Excellence for Explosives Detection.

  3. Solar heating and hot water system installed at Saint Louis, Missouri

    NASA Technical Reports Server (NTRS)

    1980-01-01

    The solar heating and hot water system installed at the William Tao & Associates, Inc., office building in St. Louis, Missouri is described, including maintenance and construction problems, final drawings, system requirements, and manufacturer's component data. The solar system was designed to provide 50 percent of the hot water requirements and 45 percent of the space heating needs for a 900 sq ft office space and drafting room. The solar facility has 252 sq ft of glass tube concentrator collectors and a 1000 gallon steel storage tank buried below a concrete slab floor. Freeze protection is provided by a propylene glycol/water mixture in the collector loop. The collectors are roof mounted on a variable tilt array which is adjusted seasonally and is connected to the solar thermal storage tank by a tube-in-shell heat exchanger. Incoming city water is preheated through the solar energy thermal storage tank.

  4. A high-stability scanning tunneling microscope achieved by an isolated tiny scanner with low voltage imaging capability.

    PubMed

    Wang, Qi; Hou, Yubin; Wang, Junting; Lu, Qingyou

    2013-11-01

    We present a novel homebuilt scanning tunneling microscope (STM) with high quality atomic resolution. It is equipped with a small but powerful GeckoDrive piezoelectric motor which drives a miniature and detachable scanning part to implement coarse approach. The scanning part is a tiny piezoelectric tube scanner (industry type: PZT-8, whose d31 coefficient is one of the lowest) housed in a slightly bigger polished sapphire tube, which is riding on and spring clamped against the knife edges of a tungsten slot. The STM so constructed shows low back-lashing and drifting and high repeatability and immunity to external vibrations. These are confirmed by its low imaging voltages, low distortions in the spiral scanned images, and high atomic resolution quality even when the STM is placed on the ground of the fifth floor without any external or internal vibration isolation devices.

  5. The effect of changes in the USF/NASA toxicity screening test method on data from some cellular polymers

    NASA Technical Reports Server (NTRS)

    Hilado, C. J.; Miller, C. M.

    1976-01-01

    Rankings of relative toxicity can be markedly affected by changes in test variables. Revision of the USF/NASA toxicity screening test procedure to eliminate the connecting tube and supporting floor and incorporate a 1.0 g sample weight, 200 C starting temperature, and 800 C upper limit temperature for pyrolysis, reversed the rankings of flexible polyurethane and polychloroprene foams, not only in relation to each other, but also in relation to cotton and red oak. Much of the change is attributed to reduction of the distance between the sample and the test animals, and reduction of the sample weight charged. Elimination of the connecting tube increased the relative toxicity of the polyurethane foams. The materials tested were flexible polyurethane foam, without and with fire retardant; rigid polyurethane foam with fire retardant; flexible polychloroprene foam; cotton, Douglas fir, red oak, hemlock, hardboard, particle board, polystyrene, and polymethyl methacrylate.

  6. Improving the reliability of road materials based on micronized sulfur composites

    NASA Astrophysics Data System (ADS)

    Abdrakhmanova, K. K.

    2015-01-01

    The work contains the results of a nano-structural modification of sulfur that prevents polymorphic transformations from influencing the properties of sulfur composites where sulfur is present in a thermodynamic stable condition that precludes destruction when operated. It has been established that the properties of sulfur-based composite materials can be significantly improved by modifying sulfur and structuring sulfur binder by nano-dispersed fiber particles and ultra-dispersed state filler. The paper shows the possibility of modifying Tengiz sulfur by its fragmenting which ensures that the structured sulfur is structurally changed and stabilized through reinforcement by ultra-dispersed fiber particles allowing the phase contact area to be multiplied. Interaction between nano-dispersed fibers of chrysotile asbestos and sulfur ensures the implementation of the mechanical properties of chrysotile asbestos tubes in reinforced composite and its integrity provided that the surface of chrysotile asbestos tubes are highly moistened with molten sulfur and there is high adhesion between the tubes and the matrix that, in addition to sulfur, contains limestone microparticles. Ability to apply materials in severe operation conditions and possibility of exposure in both aggressive medium and mechanical loads makes produced sulfur composites required by the road construction industry.

  7. Vapor spill pipe monitor

    DOEpatents

    Bianchini, G.M.; McRae, T.G.

    1983-06-23

    The invention is a method and apparatus for continually monitoring the composition of liquefied natural gas flowing from a spill pipe during a spill test by continually removing a sample of the LNG by means of a probe, gasifying the LNG in the probe, and sending the vaporized LNG to a remote ir gas detector for analysis. The probe comprises three spaced concentric tubes surrounded by a water jacket which communicates with a flow channel defined between the inner and middle, and middle and outer tubes. The inner tube is connected to a pump for providing suction, and the probe is positioned in the LNG flow below the spill pipe with the tip oriented partly downward so that LNG is continuously drawn into the inner tube through a small orifice. The probe is made of a high thermal conductivity metal. Hot water is flowed through the water jacket and through the flow channel between the three tubes to provide the necessary heat transfer to flash vaporize the LNG passing through the inner channel of the probe. The gasified LNG is transported through a connected hose or tubing extending from the probe to a remote ir sensor which measures the gas composition.

  8. Active Tube-Shaped Actuator with Embedded Square Rod-Shaped Ionic Polymer-Metal Composites for Robotic-Assisted Manipulation

    PubMed Central

    Liu, Jiayu; Zhu, Denglin; Chen, Hualing

    2018-01-01

    This paper reports a new technique involving the design, fabrication, and characterization of an ionic polymer-metal composite- (IPMC-) embedded active tube, which can achieve multidegree-of-freedom (MODF) bending motions desirable in many applications, such as a manipulator and an active catheter. However, traditional strip-type IPMC actuators are limited in only being able to generate 1-dimensional bending motion. So, in this paper, we try to develop an approach which involves molding or integrating rod-shaped IPMC actuators into a soft silicone rubber structure to create an active tube. We modified the Nafion solution casting method and developed a complete sequence of a fabrication process for rod-shaped IPMCs with square cross sections and four insulated electrodes on the surface. The silicone gel was cured at a suitable temperature to form a flexible tube using molds fabricated by 3D printing technology. By applying differential voltages to the four electrodes of each IPMC rod-shaped actuator, MDOF bending motions of the active tube can be generated. Experimental results show that such IPMC-embedded tube designs can be used for developing robotic-assisted manipulation. PMID:29770160

  9. Active Tube-Shaped Actuator with Embedded Square Rod-Shaped Ionic Polymer-Metal Composites for Robotic-Assisted Manipulation.

    PubMed

    Wang, Yanjie; Liu, Jiayu; Zhu, Denglin; Chen, Hualing

    2018-01-01

    This paper reports a new technique involving the design, fabrication, and characterization of an ionic polymer-metal composite- (IPMC-) embedded active tube, which can achieve multidegree-of-freedom (MODF) bending motions desirable in many applications, such as a manipulator and an active catheter. However, traditional strip-type IPMC actuators are limited in only being able to generate 1-dimensional bending motion. So, in this paper, we try to develop an approach which involves molding or integrating rod-shaped IPMC actuators into a soft silicone rubber structure to create an active tube. We modified the Nafion solution casting method and developed a complete sequence of a fabrication process for rod-shaped IPMCs with square cross sections and four insulated electrodes on the surface. The silicone gel was cured at a suitable temperature to form a flexible tube using molds fabricated by 3D printing technology. By applying differential voltages to the four electrodes of each IPMC rod-shaped actuator, MDOF bending motions of the active tube can be generated. Experimental results show that such IPMC-embedded tube designs can be used for developing robotic-assisted manipulation.

  10. Longer-term effects of selective thinning on microarthropod communities in a late-successional coniferous forest

    USGS Publications Warehouse

    Peck, R.W.; Niwa, C.G.

    2005-01-01

    Microarthropod densities within late-successional coniferous forests thinned 16-41 yr before sampling were compared with adjacent unthinned stands to identify longer term effects of thinning on this community. Soil and forest floor layers were sampled separately on eight paired sites. Within the forest floor oribatid, mesostigmatid, and to a marginal extent, prostigmatid mites, were reduced in thinned stands compared with unthinned stands. No differences were found for Collembola in the forest floor or for any mite suborder within the soil. Family level examination of mesostigmatid and prostigmatid mites revealed significant differences between stand types for both horizons. At the species level, thinning influenced numerous oribatid mites and Collembola. For oribatid mites, significant or marginally significant differences were found for seven of 15 common species in the forest floor and five of 16 common species in soil. Collembola were affected less, with differences found for one of 11 common species in the forest floor and three of 13 common species in soil. Multivariate analysis of variance and ordination indicated that forest thinning had little influence on the composition of oribatid mite and collembolan communities within either the forest floor or soil. Differences in microclimate or in the accumulation of organic matter on the forest floor were likely most responsible for the observed patterns of abundance. Considering the role that microarthropods play in nutrient cycling, determining the functional response of a wide range of taxa to thinning may be important to effective ecosystem management.

  11. Regional differences in the expression of laminin isoforms during mouse neural tube development

    PubMed Central

    Copp, Andrew J.; Carvalho, Rita; Wallace, Adam; Sorokin, Lydia; Sasaki, Takako; Greene, Nicholas D.E.; Ybot-Gonzalez, Patricia

    2013-01-01

    Many significant human birth defects originate around the time of neural tube closure or early during post-closure nervous system development. For example, failure of the neural tube to close generates anencephaly and spina bifida, faulty cell cycle progression is implicated in primary microcephaly, while defective migration of neuroblasts can lead to neuronal migration disorders such as lissencephaly. At the stage of neural tube closure, basement membranes are becoming organised around the neuroepithelium, and beneath the adjacent non-neural surface ectoderm. While there is circumstantial evidence to implicate basement membrane dynamics in neural tube and surface ectodermal development, we have an incomplete understanding of the molecular composition of basement membranes at this stage. In the present study, we examined the developing basement membranes of the mouse embryo at mid-gestation (embryonic day 9.5), with particular reference to laminin composition. We performed in situ hybridization to detect the mRNAs of all eleven individual laminin chains, and immunohistochemistry to identify which laminin chains are present in the basement membranes. From this information, we inferred the likely laminin variants and their tissues of origin: that is, whether a given basement membrane laminin is contributed by epithelium, mesenchyme, or both. Our findings reveal major differences in basement composition along the body axis, with the rostral neural tube (at mandibular arch and heart levels) exhibiting many distinct laminin variants, while the lumbar level where the neural tube is just closing shows a much simpler laminin profile. Moreover, there appears to be a marked difference in the extent to which the mesenchyme contributes laminin variants to the basement membrane, with potential contribution of several laminins rostrally, but no contribution caudally. This information paves the way towards a mechanistic analysis of basement membrane laminin function during early neural tube development in mammals. PMID:21524702

  12. The effect of filler content and processing variables on dimensional accuracy of experimental composite inlay material.

    PubMed

    Razak, A A; Harrison, A

    1997-04-01

    Dimensional accuracy of a composite inlay restoration is important to ensure an accurate fit and to minimize cementation stresses. A method was developed to measure dimensional accuracy and stability of a composite inlay. A standard Class II (MOD) inlay cavity stainless steel mold was made with six circular indentations placed on the occlusal floor of the cavity and four indentations on each gingival floor to act as datum points in the measurement of linear polymerization shrinkage. The inlay restorations were prepared from an inlay-onlay composite material of different filler contents (50%, 65%, and 79% by weight). For each filler content group, three curing methods were used: light curing only, light curing and heat curing at 100 degrees C for 5 minutes, and light curing and heat curing at 100 degrees C for 5 minutes and then storage in distilled water for 7 days. The accuracy of the MOD inlays was determined by measuring the shrinkage of the restoration on the occlusal floor areas and the gingival seats. The results demonstrated an inverse linear relationship between filler content and polymerization shrinkage. There was a tendency for the light-curing and heat-curing method to show an increase in polymerization shrinkage. An expansion was recorded between the mesial and distal boxes when the specimens were soaked in water for 7 days. This study suggested that the inlay mold limits the physical shrinkage that can occur between the mesial and distal axial walls of the inlay restoration because the inlay cannot shrink to a smaller dimension than the mold. Water sorption then causes hygroscopic expansion, which enlarges the distance between the mesial and distal walls.

  13. Olympus Mons, Mars: Constraints on Lava Flow Silica Composition

    NASA Astrophysics Data System (ADS)

    Kirshner, M.; Jurdy, D. M.

    2016-12-01

    Olympus Mons, Mars, the largest known volcano in our solar system, contains numerous enigmatic lava flow features. Lava tubes have received attention as their final morphologies may offer habitable zones for both native life and human exploration. Such tubes were formed through mechanisms involving several volatile species with significant silica content. Olympus Mons, a shield volcano, might be expected to have flows with silica content similar to that of terrestrial basaltic flows. However, past investigations have estimated a slightly more andesitic composition. Data pertaining to lava tubes such as flow width and slope are collected from the Mars Reconnaissance Orbiter's Context Camera, Mars Odyssey's THEMIS instrument, and Mars Express' HRSC instrument. Compiling this data in GIS software allows for extensive mapping and analysis of Olympus Mons' seemingly inactive flow features. A rheological analysis performed on 62 mapped lava tubes utilizes geometric parameters inferred from mapping. Lava was modeled as a Bingham fluid on an inclined plane, allowing for the derivation of lava yield stress. Percent silica content was calculated for each of the 62 mapped flows using a relationship derived from observations of terrestrial lava yield strengths and corresponding silica composition. Results indicate that lava tube flows across Olympus Mons were on average basaltic in nature, occasionally reaching into the andesitic classification: percent silica content is 51% on average and ranges between roughly 40% and 57%.

  14. SST Technology Follow-On Program - Phase 2. Noise Suppressor/Nozzle Development. Volume 9. Performance Technology - Analysis of the Low Speed Performance of Multitube Suppressor/Ejector Nozzles (0-167 kn)

    DTIC Science & Technology

    1975-03-01

    Layer Suction 18 Temperature and Pressure Profile at Charging Station |9 Roiind-Corivergent Reference Nozzle 20 Elliptical Ramps 21 37-Tube...between plumes of the jets in the outer row of a suppressor Homulary layer Discharge coelticient, accounting for temperature induced no/./Ie area...tunnel floor. The suppressor air tlow rate was measured with an A.S.M.H. long-radius flow nozzle. The boundary layer ihickness at the ejector inlet

  15. Fossils of hydrothermal vent worms from Cretaceous sulfide ores of the Samail ophiolite, Oman

    USGS Publications Warehouse

    Haymon, R.M.; Koski, R.A.; Sinclair, C.

    1984-01-01

    Fossil worm tubes of Cretaceous age preserved in the Bayda massive sulfide deposit of the Samail ophiolite, Oman, are apparently the first documented examples of fossils embedded in massive sulfide deposits from the geologic record. The geologic setting of the Bayda deposit and the distinctive mineralogic and textural features of the fossiliferous samples suggest that the Bayda sulfide deposit and fossil fauna are remnants of a Cretaceous sea-floor hydrothermal vent similar to modern hot springs on the East Pacific Rise and the Juan de Fuca Ridge.

  16. Development of a low-permeability glass--ceramic to seal to molybdenum. [For long-life vacuum tubes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Eagan, R. J.

    1975-03-01

    This report describes the development of low-permeability glass-ceramics which can be sealed directly to molybdenum for the purpose of producing long-life vacuum tubes. Low permeability to helium and thermal expansion match to molybdenum are the bases upon which particular glass-ceramic compositions were selected and developed. The fabrication of tube envelopes using glass-ceramics is simplified when compared to conventional ceramic/metal tubes and these melting and sealing techniques are presented.

  17. Sea-floor character and geology off the entrance to the Connecticut River, northeastern Long Island Sound

    USGS Publications Warehouse

    Poppe, Lawrence J.; McMullen, Katherine Y.; Ackerman, Seth D.; Guberski, Megan R.; Wood, Douglas A.

    2013-01-01

    Datasets of gridded multibeam bathymetry and sidescan-sonar backscatter, together covering approximately 29.1 square kilometers, were used to interpret character and geology of the sea floor off the entrance to the Connecticut River in northeastern Long Island Sound. Although originally collected for charting purposes during National Oceanic and Atmospheric Administration hydrographic survey H12013, these acoustic data, sidescan-sonar imagery, and the sea-floor sampling and photography stations subsequently occupied to verify the acoustic data (1) show the composition and terrain of the seabed, (2) provide information on sediment transport and benthic habitat, and (3) are part of an expanding series of studies that provide a fundamental framework for research and resource management (for example, cables, pipelines, and dredging) activities in this major east coast estuary.

  18. Failure Analysis of a Service Tube

    NASA Astrophysics Data System (ADS)

    Xie, Zhongdong; Cai, Weiguo; Li, Zhenxing; Guan, YiMing; Zhang, Baocheng; Yang, XiaoTong

    2017-12-01

    One tube was cracked used in the primary reformer furnace in a fertilizer plant for two and half years. In order to find out the causes of cracking, the methods for chemical composition analysis, macro- and microstructure analysis, penetrant testing, weld analysis, crack and surface damage analysis, mechanics property analysis, high temperature endurance performance analysis, stress and wall thickness calculation were adopted. The integrated assessment results showed that the carbon content of the tube was in the lower limit of the standard range; the tube effective wall thickness was too small; local overheating leads to tube cracking in use process.

  19. Method for producing a tube

    DOEpatents

    Peterson, Kenneth A [Albuquerque, NM; Rohde, Steven B [Corrales, NM; Pfeifer, Kent B [Los Lunas, NM; Turner, Timothy S [Rio Rancho, NM

    2007-01-02

    A method is described for producing tubular substrates having parallel spaced concentric rings of electrical conductors that can be used as the drift tube of an Ion Mobility Spectrometer (IMS). The invention comprises providing electrodes on the inside of a tube that are electrically connected to the outside of the tube through conductors that extend between adjacent plies of substrate that are combined to form the tube. Tubular substrates are formed from flexible polymeric printed wiring board materials, ceramic materials and material compositions of glass and ceramic, commonly known as Low Temperature Co-Fired Ceramic (LTCC). The adjacent plies are sealed together around the electrode.

  20. 16 CFR 1500.52 - Test methods for simulating use and abuse of toys and other articles intended for use by children...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...-composition tile, composition 1—asbestos free, as specified by paragraphs 1.2 and 3.1.4 of Interim Amendment-1(YD), dated November 14, 1979, to the Federal Specification entitled Tile, Floor: Asphalt, Rubber... results as, a surface covered with vinyl-asbestos tile meeting the requirements of Federal Specification...

  1. 16 CFR 1500.53 - Test methods for simulating use and abuse of toys and other articles intended for use by children...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...-composition tile, composition 1—asbestos free, as specified by paragraphs 1.2 and 3.1.4 of Interim Amendment-1(YD), dated November 14, 1979, to the Federal Specification entitled Tile, Floor: Asphalt, Rubber... results as, a surface covered with vinyl-asbestos tile meeting the requirements of Federal Specification...

  2. 16 CFR 1500.52 - Test methods for simulating use and abuse of toys and other articles intended for use by children...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...-composition tile, composition 1—asbestos free, as specified by paragraphs 1.2 and 3.1.4 of Interim Amendment-1(YD), dated November 14, 1979, to the Federal Specification entitled Tile, Floor: Asphalt, Rubber... results as, a surface covered with vinyl-asbestos tile meeting the requirements of Federal Specification...

  3. 16 CFR 1500.52 - Test methods for simulating use and abuse of toys and other articles intended for use by children...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...-composition tile, composition 1—asbestos free, as specified by paragraphs 1.2 and 3.1.4 of Interim Amendment-1(YD), dated November 14, 1979, to the Federal Specification entitled Tile, Floor: Asphalt, Rubber... results as, a surface covered with vinyl-asbestos tile meeting the requirements of Federal Specification...

  4. 16 CFR 1500.53 - Test methods for simulating use and abuse of toys and other articles intended for use by children...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...-composition tile, composition 1—asbestos free, as specified by paragraphs 1.2 and 3.1.4 of Interim Amendment-1(YD), dated November 14, 1979, to the Federal Specification entitled Tile, Floor: Asphalt, Rubber... results as, a surface covered with vinyl-asbestos tile meeting the requirements of Federal Specification...

  5. 16 CFR 1500.53 - Test methods for simulating use and abuse of toys and other articles intended for use by children...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...-composition tile, composition 1—asbestos free, as specified by paragraphs 1.2 and 3.1.4 of Interim Amendment-1(YD), dated November 14, 1979, to the Federal Specification entitled Tile, Floor: Asphalt, Rubber... results as, a surface covered with vinyl-asbestos tile meeting the requirements of Federal Specification...

  6. 16 CFR 1500.52 - Test methods for simulating use and abuse of toys and other articles intended for use by children...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...-composition tile, composition 1—asbestos free, as specified by paragraphs 1.2 and 3.1.4 of Interim Amendment-1(YD), dated November 14, 1979, to the Federal Specification entitled Tile, Floor: Asphalt, Rubber... results as, a surface covered with vinyl-asbestos tile meeting the requirements of Federal Specification...

  7. 16 CFR 1500.53 - Test methods for simulating use and abuse of toys and other articles intended for use by children...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...-composition tile, composition 1—asbestos free, as specified by paragraphs 1.2 and 3.1.4 of Interim Amendment-1(YD), dated November 14, 1979, to the Federal Specification entitled Tile, Floor: Asphalt, Rubber... results as, a surface covered with vinyl-asbestos tile meeting the requirements of Federal Specification...

  8. Forest floor community metatranscriptomes identify fungal and bacterial responses to N deposition in two maple forests

    DOE PAGES

    Hesse, Cedar N.; Mueller, Rebecca C.; Vuyisich, Momchilo; ...

    2015-04-23

    Anthropogenic N deposition alters patterns of C and N cycling in temperate forests, where forest floor litter decomposition is a key process mediated by a diverse community of bacteria and fungi. To track forest floor decomposer activity we generated metatranscriptomes that simultaneously surveyed the actively expressed bacterial and eukaryote genes in the forest floor, to compare the impact of N deposition on the decomposers in two natural maple forests in Michigan, USA, where replicate field plots had been amended with N for 16 years. Site and N amendment responses were compared using about 74,000 carbohydrate active enzyme transcript sequences (CAZymes)more » in each metatranscriptome. Parallel ribosomal RNA (rRNA) surveys of bacterial and fungal biomass and taxonomic composition showed no significant differences in either biomass or OTU richness between the two sites or in response to N. Site and N amendment were not significant variables defining bacterial taxonomic composition, but they were significant for fungal community composition, explaining 17 and 14% of the variability, respectively. The relative abundance of expressed bacterial and fungal CAZymes changed significantly with N amendment in one of the forests, and N-response trends were also identified in the second forest. Although the two ambient forests were similar in community biomass, taxonomic structure and active CAZyme profile, the shifts in active CAZyme profiles in response to N-amendment differed between the sites. One site responded with an over-expression of bacterial CAZymes, and the other site responded with an over-expression of both fungal and different bacterial CAZymes. Both sites showed reduced representation of fungal lignocellulose degrading enzymes in N-amendment plots. The metatranscriptome approach provided a holistic assessment of eukaryote and bacterial gene expression and is applicable to other systems where eukaryotes and bacteria interact.« less

  9. Fully Integral, Flexible Composite Driveshaft

    NASA Technical Reports Server (NTRS)

    Lawrie, Duncan

    2014-01-01

    An all-composite driveshaft incorporating integral flexible diaphragms was developed for prime contractor testing. This new approach makes obsolete the split lines required to attach metallic flex elements and either metallic or composite spacing tubes in current solutions. Subcritical driveshaft weights can be achieved that are half that of incumbent technology for typical rotary wing shaft lengths. Spacing tubes compose an integral part of the initial tooling but remain part of the finished shaft and control natural frequencies and torsional stability. A concurrently engineered manufacturing process and design for performance competes with incumbent solutions at significantly lower weight and with the probability of improved damage tolerance and fatigue life.

  10. Depositional facies and aqueous-solid geochemistry of travertine-depositing hot springs (Angel Terrace, Mammoth Hot Springs, Yellowstone National Park, U.S.A.)

    NASA Technical Reports Server (NTRS)

    Fouke, B. W.; Farmer, J. D.; Des Marais, D. J.; Pratt, L.; Sturchio, N. C.; Burns, P. C.; Discipulo, M. K.

    2000-01-01

    Petrographic and geochemical analyses of travertine-depositing hot springs at Angel Terrace, Mammoth Hot Springs, Yellowstone National Park, have been used to define five depositional facies along the spring drainage system. Spring waters are expelled in the vent facies at 71 to 73 degrees C and precipitate mounded travertine composed of aragonite needle botryoids. The apron and channel facies (43-72 degrees C) is floored by hollow tubes composed of aragonite needle botryoids that encrust sulfide-oxidizing Aquificales bacteria. The travertine of the pond facies (30-62 degrees C) varies in composition from aragonite needle shrubs formed at higher temperatures to ridged networks of calcite and aragonite at lower temperatures. Calcite "ice sheets", calcified bubbles, and aggregates of aragonite needles ("fuzzy dumbbells") precipitate at the air-water interface and settle to pond floors. The proximal-slope facies (28-54 degrees C), which forms the margins of terracette pools, is composed of arcuate aragonite needle shrubs that create small microterracettes on the steep slope face. Finally, the distal-slope facies (28-30 degrees C) is composed of calcite spherules and calcite "feather" crystals. Despite the presence of abundant microbial mat communities and their observed role in providing substrates for mineralization, the compositions of spring-water and travertine predominantly reflect abiotic physical and chemical processes. Vigorous CO2 degassing causes a +2 unit increase in spring water pH, as well as Rayleigh-type covariations between the concentration of dissolved inorganic carbon and corresponding delta 13C. Travertine delta 13C and delta 18O are nearly equivalent to aragonite and calcite equilibrium values calculated from spring water in the higher-temperature (approximately 50-73 degrees C) depositional facies. Conversely, travertine precipitating in the lower-temperature (< approximately 50 degrees C) depositional facies exhibits delta 13C and delta 18O values that are as much as 4% less than predicted equilibrium values. This isotopic shift may record microbial respiration as well as downstream transport of travertine crystals. Despite the production of H2S and the abundance of sulfide oxidizing microbes, preliminary delta 34S data do not uniquely define the microbial metabolic pathways present in the spring system. This suggests that the high extent of CO2 degassing and large open-system solute reservoir in these thermal systems overwhelm biological controls on travertine crystal chemistry.

  11. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Fouke, B.W.; Farmer, J.D.; Des Marais, D.J.

    Petrographic and geochemical analyses of travertine-depositing hot springs at Angel Terrace, Mammoth Hot Springs, Yellowstone National Park, have been used to define five depositional facies along the spring drainage system. Spring waters are expelled in the vent facies at 71 to 73 C and precipitate mounded travertine composed of aragonite needle botryoids. The apron and channel facies (43--72 C) is floored by hollow tubes composed of aragonite needle botryoids that encrust sulfide-oxidizing Aquificales bacteria. The travertine of the pond facies (30--62 C) varies in composition from aragonite needle shrubs formed at higher temperatures to ridged networks of calcite and aragonitemore » at lower temperatures. Calcite ice sheets, calcified bubbles, and aggregates of aragonite needles (fuzzy dumbbells) precipitate at the air-water interface and settle to pond floors. The proximal-slope facies (28--54 C), which forms the margins of terracette pools, is composed of arcuate aragonite needle shrubs that create small microterracettes on the steep slope face. Finally, the distal-slope facies (28--30 C) is composed of calcite spherules and calcite feather crystals. Despite the presence of abundant microbial mat communities and their observed role in providing substrates for mineralization, the compositions of spring-water and travertine predominantly reflect abiotic physical and chemical processes. Vigorous CO{sub 2} degassing causes a +2 unit increase in spring water pH, as well as Rayleigh-type covariations between the concentration of dissolved inorganic carbon and corresponding {delta}{sup 13}C. Travertine {delta}{sup 13}C and {delta}{sup 18}O are nearly equivalent to aragonite and calcite equilibrium values calculated from spring water in the higher-temperature ({approximately}50--73 C) depositional facies. Conversely, travertine precipitating in the lower-temperature (<{approximately}50 C) depositional facies exhibits {delta}{sup 13}C and {delta}{sup 18}O values that are as much as 4% less than predicted equilibrium values. This isotopic shift may record microbial respiration as well as downstream transport of travertine crystals. Despite the production of H{sub 2}S and the abundance of sulfide-oxidizing microbes, preliminary {delta}{sub 34}S data do not uniquely define the microbial metabolic pathways present in the spring system. This suggests that the high extent of CO{sub 2} degassing and large open-system solute reservoir in these thermal systems overwhelm biological controls on travertine crystal chemistry.« less

  12. Depositional facies and aqueous-solid geochemistry of travertine-depositing hot springs (Angel Terrace, Mammoth Hot Springs, Yellowstone National Park, U.S.A.).

    PubMed

    Fouke, B W; Farmer, J D; Des Marais, D J; Pratt, L; Sturchio, N C; Burns, P C; Discipulo, M K

    2000-05-01

    Petrographic and geochemical analyses of travertine-depositing hot springs at Angel Terrace, Mammoth Hot Springs, Yellowstone National Park, have been used to define five depositional facies along the spring drainage system. Spring waters are expelled in the vent facies at 71 to 73 degrees C and precipitate mounded travertine composed of aragonite needle botryoids. The apron and channel facies (43-72 degrees C) is floored by hollow tubes composed of aragonite needle botryoids that encrust sulfide-oxidizing Aquificales bacteria. The travertine of the pond facies (30-62 degrees C) varies in composition from aragonite needle shrubs formed at higher temperatures to ridged networks of calcite and aragonite at lower temperatures. Calcite "ice sheets", calcified bubbles, and aggregates of aragonite needles ("fuzzy dumbbells") precipitate at the air-water interface and settle to pond floors. The proximal-slope facies (28-54 degrees C), which forms the margins of terracette pools, is composed of arcuate aragonite needle shrubs that create small microterracettes on the steep slope face. Finally, the distal-slope facies (28-30 degrees C) is composed of calcite spherules and calcite "feather" crystals. Despite the presence of abundant microbial mat communities and their observed role in providing substrates for mineralization, the compositions of spring-water and travertine predominantly reflect abiotic physical and chemical processes. Vigorous CO2 degassing causes a +2 unit increase in spring water pH, as well as Rayleigh-type covariations between the concentration of dissolved inorganic carbon and corresponding delta 13C. Travertine delta 13C and delta 18O are nearly equivalent to aragonite and calcite equilibrium values calculated from spring water in the higher-temperature (approximately 50-73 degrees C) depositional facies. Conversely, travertine precipitating in the lower-temperature (< approximately 50 degrees C) depositional facies exhibits delta 13C and delta 18O values that are as much as 4% less than predicted equilibrium values. This isotopic shift may record microbial respiration as well as downstream transport of travertine crystals. Despite the production of H2S and the abundance of sulfide oxidizing microbes, preliminary delta 34S data do not uniquely define the microbial metabolic pathways present in the spring system. This suggests that the high extent of CO2 degassing and large open-system solute reservoir in these thermal systems overwhelm biological controls on travertine crystal chemistry.

  13. Frankia and Alnus rubra canopy roots: an assessment of genetic diversity, propagule availability, and effects on soil nitrogen.

    PubMed

    Kennedy, Peter G; Schouboe, Jesse L; Rogers, Rachel H; Weber, Marjorie G; Nadkarni, Nalini M

    2010-02-01

    The ecological importance of microbial symbioses in terrestrial soils is widely recognized, but their role in soils that accumulate in forest canopies is almost entirely unknown. To address this gap, this study investigated the Frankia-Alnus rubra symbiosis in canopy and forest floor roots at Olympic National Park, WA, USA. Sixteen mature A. rubra trees were surveyed and Frankia genetic diversity in canopy and forest floor nodules was assessed with sequence-based nifH analyses. A seedling bioassay experiment was conducted to determine Frankia propagule availability in canopy and forest floor soils. Total soil nitrogen from both environments was also quantified. Nodules were present in the canopies of nine of the 16 trees sampled. Across the study area, Frankia canopy and forest floor assemblages were similar, with both habitats containing the same two genotypes. The composition of forest floor and canopy genotypes on the same tree was not always identical, however, suggesting that dispersal was not a strictly local phenomenon. Frankia seedling colonization was similar in canopy soils regardless of the presence of nodules as well as in forest floor soils, indicating that dispersal was not likely to be a major limiting factor. The total soil nitrogen of canopy soils was higher than that of forest floor soils, but the presence of Frankia nodules in canopy soils did not significantly alter soil nitrogen levels. Overall, this study indicates that the Frankia-A. rubra symbiosis is similar in canopy and forest floor environments. Because canopy roots are exposed to different environmental conditions within very small spatial areas and because those areas can be easily manipulated (e.g., fertilizer or watering treatments), they present microbial ecologists with a unique arena to examine root-microbe interactions.

  14. Method of making a modified ceramic-ceramic composite

    DOEpatents

    Weaver, Billy L.; McLaughlin, Jerry C.; Stinton, David P.

    1995-01-01

    The present invention provides a method of making a shaped ceramic-ceramic composite articles, such as gas-fired radiant heat burner tubes, heat exchangers, flame dispersers, and other furnace elements, having a formed-on ceramic-ceramic composite thereon.

  15. Effects of mechanical loading on the degradability and mechanical properties of the nanocalcium-deficient hydroxyapatite–multi(amino acid) copolymer composite membrane tube for guided bone regeneration

    PubMed Central

    Duan, Hong; Yang, Hongsheng; Xiong, Yan; Zhang, Bin; Ren, Cheng; Min, Li; Zhang, Wenli; Yan, Yonggang; Li, Hong; Pei, Fuxing; Tu, Chongqi

    2013-01-01

    Background and methods Guided bone regeneration (GBR) is a new treatment for bone defects, and the property of membrane is critical to the success of GBR. This study focuses on a novel membrane tube for GBR, which was prepared by a nanocalcium-deficient hydroxyapatite–multi(amino acid) copolymer (n-CDHA-MAC) composite. The biomechanical strength and degradability of this membrane tube under mechanical loading after immersion in phosphate-buffered solution were investigated to evaluate the effects of mechanical loading on the membrane tube. The membrane-tube group with no mechanical loading and femora bone were used as controls. Results The compressive strength and bending strength of n-CDHA-MAC membrane tubes were 66.4 ± 10.2 MPa and 840.7 ± 12.1 MPa, which were lower than those of the goats’ femoral bones (69.0 ± 5.5 MPa and 900.2 ± 17.3 MPa), but there were no significant (P > 0.05) differences. In the in vitro degradability experiment, all membrane tubes were degradable and showed a surface-erosion degradation model. The PH of solution fluctuated from 7.2 to 7.5. The weight and mechanical strength of loaded tubes decreased more quickly than nonloaded ones, with significant differences (P < 0.05). However, the strength of the loaded group after degradation achieved 20.4 ± 1.2 MPa, which was greater than the maximum mechanical strength of 4.338 MPa based on goat femoral middle stationary state by three-dimensional finite-element analysis. Conclusions n-CDHA-MAC membrane tubes have good biomechanical strength during degradation under mechanical loading. Therefore, this membrane tube is an ideal GBR membrane for critical size defects of long bones in goats for animal experiments. PMID:23946651

  16. The effects of crushing speed on the energy-absorption capability of composite material

    NASA Technical Reports Server (NTRS)

    Farley, Gary L.

    1987-01-01

    The energy-absorption capability as a function of crushing speed was determined for Thornel 300/Fiberite 934 (Gr/E) and Kevlar-49/Fiberite 934 (K/E) composite material. Circular cross section tube specimens were crushed at quasi-static, 6 m/sec, and 12 m/sec speeds. Ply orientations of the tube specimens were (0/+ or - theta) sub 2 and (+ or - theta) sub 3 where theta=15, 45, and 75 degress. Based on the results of these tests the energy-absortion capability of Gr/E and K/E was determined to be a function of crushing speed. The crushing modes based on exterior appearance of the crushed tubes were unchanged for either material. However, the interlaminar crushing behavior changed with crushing speed.

  17. Dual resin bonded joints in polyetheretherketone (PEEK) matrix composites

    NASA Astrophysics Data System (ADS)

    Zelenak, Steve; Radford, Donald W.; Dean, Michael W.

    1993-04-01

    The paper describes applications of the dual resin (miscible polymer) bonding technique (Smiley, 1989) developed as an alternative to traditional bonding approaches to joining thermoplastic matrix composite subassemblies into structures. In the experiments, the performance of joint geometries, such as those that could be used to assemble large truss structures in space, are investigated using truss joint models consisting of woven carbon fiber/PEEK tubes of about 1 mm wall thickness. Specific process conditions and hand-held hardware used to apply heat and pressure were chosen to simulate a field asembly technique. Results are presented on tube/cruciform double lap shear tests, pinned-pinned tube compression tests, and single lap shear bond tests of joints obtained using the dual resin bonding technique.

  18. Assembly and remodeling of the fibrillar fibronectin extracellular matrix during gastrulation and neurulation in Xenopus laevis.

    PubMed

    Davidson, Lance A; Keller, Raymond; DeSimone, Douglas W

    2004-12-01

    Fibronectin, a major component of the extracellular matrix is critical for processes of cell traction and cell motility. Whole-mount confocal imaging of the three-dimensional architecture of the extracellular matrix is used to describe dynamic assembly and remodeling of fibronectin fibrils during gastrulation and neurulation in the early frog embryo. As previously reported, fibrils first appear under the prospective ectoderm. We describe here the first evidence for regulated assembly of fibrils along the somitic mesoderm/endoderm boundary as well as at the notochord/somitic mesoderm boundary and clearing of fibrils from the dorsal and ventral surfaces of the notochord that occurs over the course of a few hours. As gastrulation proceeds, fibrils are restored to the dorsal surface of the notochord, where the notochord contacts the prospective floor plate. As the neural folds form, fibrils are again remodeled as deep neural plate cells move medially. The process of neural tube closure leaves a region of the ectoderm overlying the neural crest transiently bare of fibrils. Fibrils are assembled surrounding the dorsal surface of the neural tube as the neural tube lumen is restored. Copyright (c) 2004 Wiley-Liss, Inc.

  19. Influence of light and darkness on the behaviour of Dermanyssus gallinae on layer farms.

    PubMed

    Sokół, R; Szkamelski, A; Barski, D

    2008-01-01

    The behaviour of Dermanyssus gallinae was investigated on two layer farms where two different light programs were introduced in the 40th week of hen life. In layer house No. 1, light was applied continuously for 16 hours during the day, while layer house No. 2 was subjected to 4 hours of light and 2 hours of darkness applied alternately during the day. To monitor the level of red mite infestation, 30 tube traps were placed in every layer house corridor at a height of 1.5 m above the floor. In the first layer house, 280 Dermanyssus gallinae females, 50 nymph larvae and 198 eggs were found in 100 mg of tube trap material during 16 hours of the light phase, while during the 8-hour darkness phase, 1240 females, 70 nymph larvae and 110 eggs were collected. In the other layer house (with an alternating light phase of 4 hours and a darkness phase of 2 hours per day), 387 Dermanyssus gallinae females, 401 nymph larvae and 1060 eggs were found in trap tubes over the 8-hour dark phase, while 343 females, 202 nymph larvae and 1106 eggs were discovered over the 16-hour light phase.

  20. Retrofitting coils

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Merrill, D.G.

    1995-12-01

    This article provides guidelines for maintaining efficiency by determining which coils require replacement and the selection of replacement coils to match the originals in terms of size, performance, materials, and material thickness. Coils in the Rio Hondo College have been in use 24 years. The author recently found an installation where the coils installed 20 years ago look like new, which is the result of a highly effective preventive maintenance program. But these exceptions are countered by some installations lasting considerably less time. Periodic coil inspections are the best way to find leaks and deterioration. Leaking coils have an unhappymore » way of announcing their presence through unwanted water on ceilings, walls, and machine room floors. Minuscule streams of water impinge on nonwater-tight housings or are picked up in the air stream to leak out of the ductwork. Coil return bends and headers seem to have the greater incidence of failure and should be checked first for pinhole or joint leaks. Also, check along the points where the tubes penetrate the tube sheets. The coil headers should be checked as should the tubes along the front and backside of the coil. The more rows the coil has, the more difficult this latter assignment becomes.« less

  1. Bacterial Community Sstructure and Novel Species of Magnetotactic Bacteria in Sediments from a Seamount in the Mariana Volcanic Arc

    NASA Astrophysics Data System (ADS)

    PAN, H.; LIU, J.; Zhang, W.; Xiao, T.; Wu, L. F.

    2017-12-01

    Seamounts are unique ecosystems where undersea mountains rise abruptly from the sea floor and interact dynamically with underwater currents, creating peculiar biological habitats with various microbial community structures. Certain bacteria associated with seamounts form conspicuous extracellular iron oxide structures, including encrusted stalks, flattened bifurcating tubes, and filamentous sheaths. To extend knowledge of seamount microorganisms we performed a systematic analysis of the population composition and occurrence of live magnetotactic bacteria (MTB) in sediments of a seamount in the Mariana volcanic arc. Proteobacteria dominated at 13 stations, and were the second in abundance to members of the Firmicutes at a deep station on a steep slope facing the Yap-Mariana trench. We found MTB that synthesize intracellular iron-oxide nanocrystals in biogenic sediments at all 14 stations, at seawater depths ranging from 238 to 2023 m. A novel flagellar apparatus, and the most complex yet reported, was observed in magnetotactic cocci; it comprises one or two bundles of 19 flagella arranged in a 3:4:5:4:3 array. Phylogenetic analysis of 16S rRNA gene sequences identified 16 novel species of MTB specific to this seamount. The geographic properties at the various stations on the seamount appear to be important in shaping the microbial community structure.

  2. Failure mechanisms in energy-absorbing composite structures

    NASA Astrophysics Data System (ADS)

    Johnson, Alastair F.; David, Matthew

    2010-11-01

    Quasi-static tests are described for determination of the energy-absorption properties of composite crash energy-absorbing segment elements under axial loads. Detailed computer tomography scans of failed specimens were used to identify local compression crush failure mechanisms at the crush front. These mechanisms are important for selecting composite materials for energy-absorbing structures, such as helicopter and aircraft sub-floors. Finite element models of the failure processes are described that could be the basis for materials selection and future design procedures for crashworthy structures.

  3. Polymeric compositions incorporating polyethylene glycol as a phase change material

    DOEpatents

    Salyer, Ival O.; Griffen, Charles W.

    1989-01-01

    A polymeric composition comprising a polymeric material and polyethylene glycol or end-capped polyethylene glycol as a phase change material, said polyethylene glycol and said end-capped polyethylene glycol having a molecular weight greater than about 400 and a heat of fusion greater than about 30 cal/g; the composition is useful in making molded and/or coated materials such as flooring, tiles, wall panels and the like; paints containing polyethylene glycols or end-capped polyethylene glycols are also disclosed.

  4. Floor plate-derived sonic hedgehog regulates glial and ependymal cell fates in the developing spinal cord.

    PubMed

    Yu, Kwanha; McGlynn, Sean; Matise, Michael P

    2013-04-01

    Cell fate specification in the CNS is controlled by the secreted morphogen sonic hedgehog (Shh). At spinal cord levels, Shh produced by both the notochord and floor plate (FP) diffuses dorsally to organize patterned gene expression in dividing neural and glial progenitors. Despite the fact that two discrete sources of Shh are involved in this process, the individual contribution of the FP, the only intrinsic source of Shh throughout both neurogenesis and gliogenesis, has not been clearly defined. Here, we have used conditional mutagenesis approaches in mice to selectively inactivate Shh in the FP (Shh(FP)) while allowing expression to persist in the notochord, which underlies the neural tube during neurogenesis but not gliogenesis. We also inactivated Smo, the common Hh receptor, in neural tube progenitors. Our findings confirm and extend prior studies suggesting an important requirement for Shh(FP) in specifying oligodendrocyte cell fates via repression of Gli3 in progenitors. Our studies also uncover a connection between embryonic Shh signaling and astrocyte-mediated reactive gliosis in adults, raising the possibility that this pathway is involved in the development of the most common cell type in the CNS. Finally, we find that intrinsic spinal cord Shh signaling is required for the proper formation of the ependymal zone, the epithelial cell lining of the central canal that is also an adult stem cell niche. Together, our studies identify a crucial late embryonic role for Shh(FP) in regulating the specification and differentiation of glial and epithelial cells in the mouse spinal cord.

  5. High through-plane thermal conduction of graphene nanoflake filled polymer composites melt-processed in an L-shape kinked tube.

    PubMed

    Jung, Haejong; Yu, Seunggun; Bae, Nam-Seok; Cho, Suk Man; Kim, Richard Hahnkee; Cho, Sung Hwan; Hwang, Ihn; Jeong, Beomjin; Ryu, Ji Su; Hwang, Junyeon; Hong, Soon Man; Koo, Chong Min; Park, Cheolmin

    2015-07-22

    Design of materials to be heat-conductive in a preferred direction is a crucial issue for efficient heat dissipation in systems using stacked devices. Here, we demonstrate a facile route to fabricate polymer composites with directional thermal conduction. Our method is based on control of the orientation of fillers with anisotropic heat conduction. Melt-compression of solution-cast poly(vinylidene fluoride) (PVDF) and graphene nanoflake (GNF) films in an L-shape kinked tube yielded a lightweight polymer composite with the surface normal of GNF preferentially aligned perpendicular to the melt-flow direction, giving rise to a directional thermal conductivity of approximately 10 W/mK at 25 vol % with an anisotropic thermal conduction ratio greater than six. The high directional thermal conduction was attributed to the two-dimensional planar shape of GNFs readily adaptable to the molten polymer flow, compared with highly entangled carbon nanotubes and three-dimensional graphite fillers. Furthermore, our composite with its density of approximately 1.5 g/cm(3) was mechanically stable, and its thermal performance was successfully preserved above 100 °C even after multiple heating and cooling cycles. The results indicate that the methodology using an L-shape kinked tube is a new way to achieve polymer composites with highly anisotropic thermal conduction.

  6. Comparisons of the Impact Responses of a 1/5-Scale Model and a Full-Scale Crashworthy Composite Fuselage Section

    NASA Technical Reports Server (NTRS)

    Jackson, Karen E.; Fasanella, Edwin L.; Lyle, Karen H.

    2003-01-01

    A 25-fps vertical drop test of a 1/5-scale model composite fuselage section was conducted to replicate a previous test of a full-scale fuselage section. The purpose of the test was to obtain experimental data characterizing the impact response of the 1/5-scale model fuselage section for comparison with the corresponding full-scale data. This comparison is performed to assess the scaling procedures and to determine if scaling effects are present. For the drop test, the 1/5-scale model fuselage section was configured in a similar manner as the full-scale section, with lead masses attached to the floor through simulated seat rails. Scaled acceleration and velocity responses are compared and a general assessment of structural damage is made. To further quantify the data correlation, comparisons of the average acceleration data are made as a function of floor location and longitudinal position. Also, the percentage differences in the velocity change (area under the acceleration curve) and the velocity change squared (proportional to kinetic energy) are compared as a function of floor location. Finally, correlation coefficients are calculated for corresponding 1/5- and full-scale data channels and these values are plotted versus floor location. From a scaling perspective, the differences between the 1/5- and full-scale tests are relatively small, indicating that appropriate scaling procedures were used in fabricating the test specimens and in conducting the experiments. The small differences in the scaled test data are attributed to minor scaling anomalies in mass, potential energy, and impact attitude.

  7. Manning's roughness coefficient for buried composite arch bridges.

    DOT National Transportation Integrated Search

    2014-08-01

    This report includes fulfillment of Task 9 of a multi-task contract to further enhance concrete filled FRP tubes, or : the Bridge in a Backpack. Task 9 investigates the interaction of water flow under the bridge with the tubes and : decking and recom...

  8. 16 CFR § 1500.52 - Test methods for simulating use and abuse of toys and other articles intended for use by children...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... IV vinyl-composition tile, composition 1—asbestos free, as specified by paragraphs 1.2 and 3.1.4 of Interim Amendment-1(YD), dated November 14, 1979, to the Federal Specification entitled Tile, Floor... test results as, a surface covered with vinyl-asbestos tile meeting the requirements of Federal...

  9. 16 CFR 1500.51 - Test methods for simulating use and abuse of toys and other articles intended for use by children...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...-centimeter) nominal thickness of type IV vinyl-composition tile, composition 1—asbestos free, as specified by... entitled Tile, Floor: Asphalt, Rubber, Vinyl, Vinyl-Asbestos, SS-T-312B, dated October 10, 1974, 1 over at..., and will yield the same impact test results as, a surface covered with vinyl-asbestos tile meeting the...

  10. 16 CFR § 1500.53 - Test methods for simulating use and abuse of toys and other articles intended for use by children...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... IV vinyl-composition tile, composition 1—asbestos free, as specified by paragraphs 1.2 and 3.1.4 of Interim Amendment-1(YD), dated November 14, 1979, to the Federal Specification entitled Tile, Floor... test results as, a surface covered with vinyl-asbestos tile meeting the requirements of Federal...

  11. 16 CFR 1500.51 - Test methods for simulating use and abuse of toys and other articles intended for use by children...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...-centimeter) nominal thickness of type IV vinyl-composition tile, composition 1—asbestos free, as specified by... entitled Tile, Floor: Asphalt, Rubber, Vinyl, Vinyl-Asbestos, SS-T-312B, dated October 10, 1974, 1 over at..., and will yield the same impact test results as, a surface covered with vinyl-asbestos tile meeting the...

  12. 16 CFR 1500.51 - Test methods for simulating use and abuse of toys and other articles intended for use by children...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...-centimeter) nominal thickness of type IV vinyl-composition tile, composition 1—asbestos free, as specified by... entitled Tile, Floor: Asphalt, Rubber, Vinyl, Vinyl-Asbestos, SS-T-312B, dated October 10, 1974, 1 over at..., and will yield the same impact test results as, a surface covered with vinyl-asbestos tile meeting the...

  13. 16 CFR 1500.51 - Test methods for simulating use and abuse of toys and other articles intended for use by children...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...-centimeter) nominal thickness of type IV vinyl-composition tile, composition 1—asbestos free, as specified by... entitled Tile, Floor: Asphalt, Rubber, Vinyl, Vinyl-Asbestos, SS-T-312B, dated October 10, 1974, 1 over at..., and will yield the same impact test results as, a surface covered with vinyl-asbestos tile meeting the...

  14. Sea-floor geology and sedimentary processes in the vicinity of Cross Rip Channel, Nantucket Sound, offshore southeastern Massachusetts

    USGS Publications Warehouse

    Poppe, L.J.; McMullen, K.Y.; Ackerman, S.D.; Schaer, J.D.; Wright, D.B.

    2012-01-01

    Gridded multibeam bathymetry covers approximately 10.4 square kilometers of sea floor in the vicinity of Cross Rip Channel in Nantucket Sound, offshore southeastern Massachusetts. Although originally collected for charting purposes during National Oceanic and Atmospheric Administration hydrographic survey H12007, these acoustic data, and the sea-floor sediment sampling and bottom photography stations subsequently occupied to verify them, show the composition and terrain of the seabed and provide information on sediment transport and benthic habitat. This report is part of an expanding series of cooperative studies by the U.S. Geological Survey, National Oceanic and Atmospheric Administration, and Massachusetts Office of Coastal Zone Management that provide a fundamental framework for research and resource-management activities (for example, windfarms, pipelines, and dredging) along the inner continental shelf offshore of Massachusetts.

  15. 8. Building G9; view of No. 8 condenser and top ...

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

    8. Building G-9; view of No. 8 condenser and top of dissolve tank; third floor, looking S. (Ryan) - Holston Army Ammunition Plant, RDX-and-Composition-B Manufacturing Line 9, Kingsport, Sullivan County, TN

  16. A new biphasic osteoinductive calcium composite material with a negative Zeta potential for bone augmentation

    PubMed Central

    Smeets, Ralf; Kolk, Andreas; Gerressen, Marcus; Driemel, Oliver; Maciejewski, Oliver; Hermanns-Sachweh, Benita; Riediger, Dieter; Stein, Jamal M

    2009-01-01

    The aim of the present study was to analyze the osteogenic potential of a biphasic calcium composite material (BCC) with a negative surface charge for maxillary sinus floor augmentation. In a 61 year old patient, the BCC material was used in a bilateral sinus floor augmentation procedure. Six months postoperative, a bone sample was taken from the augmented regions before two titanium implants were inserted at each side. We analyzed bone neoformation by histology, bone density by computed tomography, and measured the activity of voltage-activated calcium currents of osteoblasts and surface charge effects. Control orthopantomograms were carried out five months after implant insertion. The BCC was biocompatible and replaced by new mineralized bone after being resorbed completely. The material demonstrated a negative surface charge (negative Zeta potential) which was found to be favorable for bone regeneration and osseointegration of dental implants. PMID:19523239

  17. Fabrication of MgB2 monofilament wire by in-situ using powder-in-tube (PIT) method

    NASA Astrophysics Data System (ADS)

    Rasyadi, Muhammad Emir Hanif; Yudanto, Sigit Dwi; Imaduddin, Agung; Sawitri, Dyah

    2018-04-01

    In this research we have studied the making of MgB2 superconducting monofilament wire using powder-in-tube method with variation of Mg composition to B ie 0.90, 1.00 and 1.10, while Boron remains The precursor used is Mg powder (98%) and powder B (95%) Both materials are mixed and then crushed with agate mortar for 30 minutes and then put into stainless steel tube 316. The tube is then subjected to a mechanical treatment of rolling to form its monofilament wire. The wire is then cut and sintered at a temperature of 800o C for 2 hours. After that we measure the critical temperature then characterize the samples by XRD and SEM. From the result of this research it was found that in-situ wire-making by powder-in-tube method can make MgB2 superconducting monofilament wire with MgB2 as the dominant phase around 95% and MgO as the impurity phase around 5%. MgO is formed due to the oxidation occurring in the MgB2 powder inside the wire. The optimal Mg:B composition to make this wire is in the 1:2 composition Because it has a good resistivity curve with a high enough Tc Onset that is 41,67 K and Tc Zero 40,89 K. However, there is a porosity in the wire due to the volume reduction of the Mg + 2B reaction plus the evaporation of Mg.

  18. Lightweight thermally efficient composite feedlines, preliminary design and evaluation. [for the space tug propulsion system

    NASA Technical Reports Server (NTRS)

    Spond, D. E.; Holzworth, R. E.; Hall, C. A.

    1974-01-01

    Six liquid hydrogen feedline design concepts were developed for the cryogenic space tug. The feedlines include composite and all-metal vacuum jacketed and non-vacuum jacketed concepts, and incorporate the latest technology developments in the areas of thermally efficient vacuum jacket end closures and standoffs, radiation shields in the vacuum annulus, thermal coatings, and lightweight dissimilar metal flanged joints. The feedline design concepts were evaluated on the basis of thermal performance, weight, cost, reliability, and reusability. It is shown that composite tubing provides improved thermal performance and reduced weight for each design concept considered. Approximately 12 kg (26 lb.) can be saved by the use of composite tubing for the LH2 feedline and the other propulsion lines in the space tug.

  19. Bacterial diversity of floor drain biofilms and drain waters in a Listeria monocytogenes contaminated food processing environment.

    PubMed

    Dzieciol, Monika; Schornsteiner, Elisa; Muhterem-Uyar, Meryem; Stessl, Beatrix; Wagner, Martin; Schmitz-Esser, Stephan

    2016-04-16

    Sanitation protocols are applied on a daily basis in food processing facilities to prevent the risk of cross-contamination with spoilage organisms. Floor drain water serves along with product-associated samples (slicer dust, brine or cheese smear) as an important hygiene indicator in monitoring Listeria monocytogenes in food processing facilities. Microbial communities of floor drains are representative for each processing area and are influenced to a large degree by food residues, liquid effluents and washing water. The microbial communities of drain water are steadily changing, whereas drain biofilms provide more stable niches. Bacterial communities of four floor drains were characterized using 16S rRNA gene pyrosequencing to better understand the composition and exchange of drain water and drain biofilm communities. Furthermore, the L. monocytogenes contamination status of each floor drain was determined by applying cultivation-independent real-time PCR quantification and cultivation-dependent detection according to ISO11290-1. Pyrosequencing of 16S rRNA genes of drain water and drain biofilm bacterial communities yielded 50,611 reads, which were clustered into 641 operational taxonomic units (OTUs), affiliated to 16 phyla dominated by Proteobacteria, Firmicutes and Bacteroidetes. The most abundant OTUs represented either product- (Lactococcus lactis) or fermentation- and food spoilage-associated phylotypes (Pseudomonas mucidolens, Pseudomonas fragi, Leuconostoc citreum, and Acetobacter tropicalis). The microbial communities in DW and DB samples were distinct in each sample type and throughout the whole processing plant, indicating the presence of indigenous specific microbial communities in each processing compartment. The microbiota of drain biofilms was largely different from the microbiota of the drain water. A sampling approach based on drain water alone may thus only provide reliable information on planktonic bacterial cells but might not allow conclusions on the bacterial composition of the microbiota in biofilms. Copyright © 2016. Published by Elsevier B.V.

  20. Continuous Fiber Ceramic Composite (CFCC) Program: Gaseous Nitridation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    R. Suplinskas G. DiBona; W. Grant

    2001-10-29

    Textron has developed a mature process for the fabrication of continuous fiber ceramic composite (CFCC) tubes for application in the aluminum processing and casting industry. The major milestones in this project are System Composition; Matrix Formulation; Preform Fabrication; Nitridation; Material Characterization; Component Evaluation

  1. Synthesis and characterization of Fe(III)-silicate precipitation tubes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Parmar, K.; Pramanik, A.K.; Bandyopadhya, N.R.

    2010-09-15

    Fe(III)-silicate precipitation tubes synthesized through 'silica garden' route have been characterized using a number of analytical techniques including X-ray diffraction, infrared spectroscopy, atomic force microscopy, scanning and transmission electron microscopy. These tubes are brittle and amorphous and are hierarchically built from smaller tubes of 5-10 nm diameters. They remain amorphous at least up to 650 {sup o}C. Crystobalite and hematite are the major phases present in Fe(III)-silicate tubes heated at 850 {sup o}C. Morphology and chemical compositions at the external and internal walls of these tubes are remarkably different. These tubes are porous with high BET surface area of 291.2more » m{sup 2}/g. Fe(III)-silicate tubes contain significant amount of physically and chemically bound moisture. They show promise as an adsorbent for Pb(II), Zn(II), and Cr(III) in aqueous medium.« less

  2. Proving the viability of manufacturing of multi-layer steel/vanadium alloy/steel composite tubes by numerical simulations and experiment

    NASA Astrophysics Data System (ADS)

    Nechaykina, T.; Nikulin, S.; Rozhnov, A.; Molotnikov, A.; Zavodchikov, S.; Estrin, Y.

    2018-05-01

    Vanadium alloys are promising structural materials for fuel cladding tubes for fast-neutron reactors. However, high solubility of oxygen and nitrogen in vanadium alloys at operating temperatures of 700 °C limits their application. In this work, we present a novel composite structure consisting of vanadium alloy V-4Ti-4Cr (provides high long-term strength of the material) and stainless steel Fe-0.2C-13Cr (as a corrosion resistant protective layer). It is produced by co-extrusion of these materials forming a three-layered tube. Finite element simulations were utilised to explore the influence of the various co-extrusion parameters on manufacturability of multi-layered tubes. Experimental verification of the numerical modelling was performed using co-extrusion with the process parameters suggested by the numerical simulations. Scanning electron microscopy and microhardness measurements revealed a defect-free diffusion layer at the interfaces between both materials indicating a good quality bonding for these co-extrusion conditions.

  3. Thermal Analysis for Ion-Exchange Column System

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lee, Si Y.; King, William D.

    2012-12-20

    Models have been developed to simulate the thermal characteristics of crystalline silicotitanate ion exchange media fully loaded with radioactive cesium either in a column configuration or distributed within a waste storage tank. This work was conducted to support the design and operation of a waste treatment process focused on treating dissolved, high-sodium salt waste solutions for the removal of specific radionuclides. The ion exchange column will be installed inside a high level waste storage tank at the Savannah River Site. After cesium loading, the ion exchange media may be transferred to the waste tank floor for interim storage. Models weremore » used to predict temperature profiles in these areas of the system where the cesium-loaded media is expected to lead to localized regions of elevated temperature due to radiolytic decay. Normal operating conditions and accident scenarios (including loss of solution flow, inadvertent drainage, and loss of active cooling) were evaluated for the ion exchange column using bounding conditions to establish the design safety basis. The modeling results demonstrate that the baseline design using one central and four outer cooling tubes provides a highly efficient cooling mechanism for reducing the maximum column temperature. In-tank modeling results revealed that an idealized hemispherical mound shape leads to the highest tank floor temperatures. In contrast, even large volumes of CST distributed in a flat layer with a cylindrical shape do not result in significant floor heating.« less

  4. Forming of complex-shaped composite tubes using optimized bladder-assisted resin transfer molding

    NASA Astrophysics Data System (ADS)

    Schillfahrt, Christian; Fauster, Ewald; Schledjewski, Ralf

    2018-05-01

    This work addresses the manufacturing of tubular composite structures by means of bladder-assisted resin transfer molding using elastomeric bladders. In order to achieve successful processing of such parts, knowledge of the compaction and impregnation behavior of the textile preform is vital. Hence, efficient analytical models that describe the influencing parameters of the preform compaction and filling stage were developed and verified through practical experiments. A process window describing optimal and critical operating conditions during the injection stage was created by evaluating the impact of the relevant process pressures on filling time. Finally, a cascaded injection procedure was investigated that particularly facilitates the manufacturing of long composite tubes.

  5. Effect of triggering angles on the crushing mechanisms of hybrid woven kenaf/aluminum hollow cylinders

    NASA Astrophysics Data System (ADS)

    Ismail, Al Emran; Mat Noor, Fazimah; Mohamad, Zaleha; Amran Madlan, Mohd; Zulafif Rahim, M.; Rasidi Ibrahim, M.; Ahmad, Sufizar; Nasrull Abdol Rahman, Mohd; Salleh, Salihatun Md; Sadikin, Azmahani; Mahzan, Shahruddin; Nor, Nik Hisyamudin Muhd

    2017-10-01

    This paper presents the effect of triggering angles constructed on the top of hybrid woven kenaf/aluminium hollow cylinders on the energy absorption performances. The crushing performances of aluminium tubes can be found widely in open literature. However, lack number of work on the hybridizing the aluminium tubes with woven kenaf fibre is found. Woven kenaf mats are produced and bathed with polymeric resin before they are wrapped around the aluminium tubes twice. Different fibre orientations, ±θ° are used where θ = 0, 15, 30 and 45. Once the hybrid composite hardened, one of their end are chamfered using different angles of 0°, 30°, 45° and 60°. The tubes are quasi-statically compressed in order to obtain their force-displacement responses and crashworthiness parameters are extracted and discussed with the relation of fibre orientations and chamfering angles. It is found that the chamfering angles are only affected the force-displacement curves during the first stage of elastic deformation whereas there is no obvious effect in the second stage. However, varying the fibre orientations are slightly increased the force-displacement curves especially when the fibre is orientated with 30°. Based on the fracture mechanism observations, most of composite experienced large fragmentation indicating that the composites absorbed the crushing energy ineffectively.

  6. Agglutinates as recorders of fossil soil compositions. [of Apollo 17 lunar probes

    NASA Technical Reports Server (NTRS)

    Taylor, G. J.; Wentworth, S.; Warner, R. D.; Keil, K.

    1978-01-01

    The composition of agglutinates in polished sections of the Apollo 17 drill core was studied in an attempt to deduce the nature of the Taurus-Littrow valley regolith prior to the formation of the Camelot and Central Cluster craters. The agglutinate compositions in the soils differed from the host soil compositions except for samples from the North Massif. Local materials from the valley floor and the massifs appear to form the pre-Central Cluster regolith. It is also shown that chemical mixing models for bulk soil compositions can be misleading unless the petrologic characteristics of each soil are taken into account.

  7. Stress analysis and failure of an internally pressurized composite-jacketed steel cylinder

    NASA Technical Reports Server (NTRS)

    Chen, Peter C. T.

    1992-01-01

    This paper presents a nonlinear stress analysis of a thick-walled compound tube subjected to internal pressure. The compound tube is constructed of a steel liner and a graphite-bismaleimide outer shell. Analytical expressions for the stresses, strains, and displacements are derived for all loading ranges up to failure. Numerical results for the stresses and the maximum value that the compound tube can contain without failure are presented.

  8. Investigating Mars: Arsia Mons

    NASA Image and Video Library

    2018-01-04

    The three large aligned Tharsis volcanoes are Arsia Mons, Pavonis Mons and Ascreaus Mons (from south to north). There are collapse features on all three volcanoes, on the southwestern and northeastern flanks. This alignment may indicate a large fracture/vent system was responsible for the eruptions that formed all three volcanoes. This VIS image shows part of the southern flank of Arsia Mons, along the center of the aligned fracture system. The scalloped depressions are most likely created by collapse of the roof of lava tubes. Lava tubes originate during eruption event, when the margins of a flow harden around a still flowing lava stream. When an eruption ends these can become hollow tubes within the flow. With time, the roof of the tube may collapse into the empty space below. The tubes are linear, so the collapse of the roof creates a linear depression. In this region, the complexity of the collapse and faulting has created a unique surface. This region has collapse depressions with floors at a variety of elevations, landslide deposits where material has continued to fall into the depression and depression sizes from small to large. Arsia Mons is the southernmost of the Tharsis volcanoes. It is 270 miles (450km) in diameter, almost 12 miles (20km) high, and the summit caldera is 72 miles (120km) wide. For comparison, the largest volcano on Earth is Mauna Loa. From its base on the sea floor, Mauna Loa measures only 6.3 miles high and 75 miles in diameter. A large volcanic crater known as a caldera is located at the summit of all of the Tharsis volcanoes. These calderas are produced by massive volcanic explosions and collapse. The Arsia Mons summit caldera is larger than many volcanoes on Earth. The Odyssey spacecraft has spent over 15 years in orbit around Mars, circling the planet more than 69000 times. It holds the record for longest working spacecraft at Mars. THEMIS, the IR/VIS camera system, has collected data for the entire mission and provides images covering all seasons and lighting conditions. Over the years many features of interest have received repeated imaging, building up a suite of images covering the entire feature. From the deepest chasma to the tallest volcano, individual dunes inside craters and dune fields that encircle the north pole, channels carved by water and lava, and a variety of other feature, THEMIS has imaged them all. For the next several months the image of the day will focus on the Tharsis volcanoes, the various chasmata of Valles Marineris, and the major dunes fields. We hope you enjoy these images! Orbit Number: 33925 Latitude: -10.6619 Longitude: 239.412 Instrument: VIS Captured: 2009-08-07 16:10 https://photojournal.jpl.nasa.gov/catalog/PIA22158

  9. Stresses and deformations in angle-ply composite tubes

    NASA Technical Reports Server (NTRS)

    Rousseau, Carl Q.; Hyer, Michael W.; Tompkins, Stephen S.

    1987-01-01

    The stress and deformations in angle-ply composite tubes subjected to axisymmetric thermal loading were investigated both experimentally and analytically. For the theoretical portion a generalized plane strain elasticity analysis was developed. The analysis included mechanical and thermal loading, and temperature-dependent material properties. The elasticity analysis was also used to study the effect of including a thin metallic coating on a graphite-epoxy tube. The stresses in the coatings were found to be quite high, exceeding the yield stress of aluminum. An important finding in the analytical studies was the fact that even tubes with a balanced-symmetric lamination sequence exhibit shear deformation, or twist. For the experimental portion an apparatus was developed to measure torsional and axial response in the temperature range of 140 to 360 K. Eighteen specimens were tested, combining three material systems, eight lamination sequences, and three off-axis ply orientation angles. For the twist response, agreement between analysis and experiment was found to be good. The axial response of the tubes tested was found to be greater than predicted by a factor of three. As a result, it is recommended that the thermally induced axial deformations be investigated, both experimentally and analytically.

  10. Stresses and deformations in cross-ply composite tubes subjected to a uniform temperature change

    NASA Technical Reports Server (NTRS)

    Hyer, M. W.; Cooper, D. E.; Cohen, D.

    1986-01-01

    This study investigates the effects of a uniform temperature change on the stresses and deformations of composite tubes and determines the accuracy of an approximate solution based on the principle of complementary virtual work. Interest centers on tube response away from the ends and so a planar elasticity approach is used. For the approximate solution a piecewise linear variation of stresses with the radial coordinate is assumed. The results from the approximate solution are compared with the elasticity solution. The stress predictions agree well, particularly peak interlaminar stresses. Surprisingly, the axial deformations also agree well, despite the fact that the deformations predicted by the approximate solution do not satisfy the interface displacement continuity conditions required by the elasticity solution. The study shows that the axial thermal expansion coefficient of tubes with a specific number of axial and circumferential layers depends on the stacking sequence. This is in contrast to classical lamination theory, which predicts that the expansion will be independent of the stacking arrangement. As expected, the sign and magnitude of the peak interlaminar stresses depend on stacking sequence. For tubes with a specific number of axial and circumferential layers, thermally induced interlaminar stresses can be controlled by altering stacking arrangement.

  11. Comparison of survivability of Staphylococcus aureus and spores of Aspergillus niger on commonly used floor materials.

    PubMed

    Gupta, Mridula; Bisesi, Michael; Lee, Jiyoung

    2017-07-01

    The survivability of Staphylococcus aureus and spores of Aspergillus niger was compared on 5 common floor materials. Floor materials were inoculated with a known concentration of S aureus and spores of A niger on day 0. Their survivability was measured on days, 2, 7, 14, and 28 by bulk rinsate method and enumerated using culture-based method. The difference in change of S aureus levels was statistically significant for all tested days (P < .001) for all floor materials. Vinyl composition tile (VCT) and porcelain tile (PT) had statistically similar survivability and differed statistically from carpets. On both VCT and PT, positive growth for S aureus occurred by day 2 (1-1.7 log 10 ), declined slightly (0.1 to -0.2 log 10 ) by day 7, and remained positive until day 28. However, S aureus was undetected by day 7 on both carpets. A niger spores were undetected on residential broadloom carpet and rubber-backed commercial carpet after day 2 but survived on VCT, PT, and wood until day 28. Floor materials with hard and smooth surfaces, such as VCT and PT, can allow survival of S aureus and A niger for up to 4 weeks. It may imply that floor materials can play a major role in preserving microbial contaminants in the built environment. Copyright © 2017 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

  12. The universal applications of microtubes and microtube composites

    NASA Technical Reports Server (NTRS)

    Hoffman, Wesley P.; Upadhya, Kamleshwar

    1994-01-01

    Microtubes are a basic component for a myriad of potential products. They are very small tubes (hundreds can fit in a human hair) that can be made from practically any material. Tubes larger than 1 micron diameter can be made with any cross-sectional shape desired. The significance of microtubes and microtube composites is that they provide the opportunity to miniaturize (even to the nanoscale) numerous products and devices that are currently in existence as well as allowing the fabrication of products that have to date been impossible to produce.

  13. Demonstration of Advanced C/SiC Cooled Ramp

    NASA Technical Reports Server (NTRS)

    Bouquet, Clement; Laithier, Frederic; Lawrence, Timothy; Eckel, Andrew; Munafo, Paul M. (Technical Monitor)

    2002-01-01

    Under a NASA contract, SPS is evaluating its C/SiC to metal brazing technique for the development of light, composite, actively cooled panels. The program first consisted of defining a system applicable to the X-33 nozzle ramp. SPS then performed evaluation tests for tube, composite, and braze material selection, and for the adaptation of braze process parameters to the parts geometry. SPS is presently manufacturing a 250x60 millimeter squared specimen, including 10 metallic tubes, which will be cycled in the NASA/GRC-CELL-22 test bed under engine representative conditions.

  14. Analogy for the effect of material and geometrical variables on energy-absorption capability of composite tubes

    NASA Technical Reports Server (NTRS)

    Farley, Gary L.; Jones, Robert M.

    1992-01-01

    Simplified procedures for determining the qualitative effect a variable has on structural response of a composite tube are very useful in both preliminary design as well as in providing insight into the general response. An analysis procedure is presented that can be used to determine the qualitative change in the sustained crushing load due to a change in specimen material properties or geometry. The analysis procedure is similar in form to the equation for the buckling load of a column on an elastic foundation.

  15. 93. View of transmitter building no. 102 view from second ...

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

    93. View of transmitter building no. 102 view from second floor at grid lines 102-J-L, looking down at capacitor vaults on left and Klystron tube vaults on right showing future square attachment blockouts for waveguide connections at top. RCA Services Company 27 October, 1960, official photograph BMEWS Project by unknown photograph, Photographic Services, Riverton, NJ, BMEWS, clear as negative no. A-1371. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

  16. Expressly fabricated molar tube bases: enhanced adhesion.

    PubMed

    Sharma, Tarun; Phull, Tarun Singh; Rana, Tarun; Kumar, Varun

    2014-06-01

    Clinicians, Orthodontists and their patients' parents often expect the best results in the shortest time span possible. Orthodontic bonding of molar tubes has been an acceptable risk in a modern era of refined biomaterials and instrumentation. Although many orthodontists still prefer banding to bonding, it is the failure rate of the tubes on molars which accounts to an impedance in molar bonding. One of the reasons for molar attachment failures is attributed to improper adaptation of the buccal tube base with or without increased thickness of composite. Merits of banding the second molars especially when these are the terminal teeth for anchorage have been overemphasized in the literature. The present article presents a simple and relatively less time consuming technique of preparing molar tubes to be bonded on tooth surfaces which may be quite difficult to isolate especially for bonding, for example, mandibular second molars. The increased surface area of the composite scaffold helps not only in enhanced bond strength but also serves to reduce the incidence of plaque accumulation given the dexterity of invitro preparation. The removal of the occlusal part of the molar tube scaffold helps in prevention of open / raised bite tendencies. The present innovation, therefore, is not merely serendipity but a structured technique to overcome a common dilemma for the clinical orthodontist. The present dictum of banding being superior to molar tube bonding may prove to be futile with trendsetting molar attachments. It is also an established fact that bonding proves to be a lesser expensive modality when compared to banding procedures.

  17. 16 CFR § 1500.51 - Test methods for simulating use and abuse of toys and other articles intended for use by children...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... (0.3-centimeter) nominal thickness of type IV vinyl-composition tile, composition 1—asbestos free, as... Specification entitled Tile, Floor: Asphalt, Rubber, Vinyl, Vinyl-Asbestos, SS-T-312B, dated October 10, 1974, 1... equivalent of, and will yield the same impact test results as, a surface covered with vinyl-asbestos tile...

  18. Mini-CORK observatories using the MeBo seafloor drill rig - a new development for long-term data acquisition and sampling in shallow boreholes

    NASA Astrophysics Data System (ADS)

    Kopf, A.; Freudenthal, T.; Ratmeyer, V.; Bergenthal, M.; Renken, J.; Zabel, M.; Wefer, G.

    2011-12-01

    State of the art technology for long-term monitoring of fluid migration within the sea floor is the sealing of a borehole with a Circulation Obviation Retrofit Kit (CORK) after sensor installation and/or fluid sampling devices within the drill string. However, the combined used of a drilling vessels and a remotely operated drilling (ROV) required for a CORK installation in the deep sea is a costly exercise that limits the number of monitoring stations installed. Robotic sea floor drill rigs are a cost effective alternative for shallow drillings down to 50-100 m below sea floor. Here we present a Mini-CORK system that is developed for installation with the sea floor drill rig MeBo. This rig was developed at MARUM Research Centre, University of Bremen in 2005 and can sample the sea floor in water depths up to 2000 m. The MeBo is deployed on the seabed and remotely controlled from the vessel. All required drill tools for wire-line core drilling down to 70 m below sea floor are stored on two rotating magazines and can be loaded below the top drive drill head for assembling the drill string. For one of the upcoming cruises with RV Sonne offshore Japan (Nankai Trough accretionary prism), MeBo will be used for the first time to place observatories. Two different designs have been developed. The first, relatively simple long-term device resembles a MeBo drill rod in its geometry, and contains a pressure and temperature transducer in the borehole plus an identical pair of transducers for seafloor reference. The device also contains a data logger, battery unit, and an acoustic modem so that data can be downloaded at any time from a ship of opportunity. The key element at the base of the observatory rod is a seal at the conical thread to separate the borehole hydraulically from the overlying water body. It is realized by an adapter, which also contains a hotstab hydraulic connection and an electrical connection. The second observatory device is a seafloor unit, which replaces part of the first unit and which is deployed by ROV. In essence, the upper portion of the former observatory is taken away by ROV, and an umbilical containing hydraulic lines and tubing to withdraw formation water from the borehole is plugged into the hotstab female adapter by ROV. At the far end, the umbilical is connected to a seafloor unit with battery power, data logger, P and T transducers, and the same acoustic modem as the former one. In addition, the latter contains osmo samplers and biological chambers (FLOCS) for in situ sampling and experiments. After the envisaged deployment period, the entire unit is replaced while an identical one is prepared on deck and lowered from the vessel. In theory, the MeBo hole infinitely serves as an access to depth since no electronic, but only tubing is lowered into the (open) hole. In summary, long-term borehole installations with MeBo offer an affordable way to measure key physical properties over time and sample the formation fluids for geochemistry and microbiology (in case of the second, ROV-deployed CORK).

  19. Nectar sugar composition of European Caryophylloideae (Caryophyllaceae) in relation to flower length, pollination biology and phylogeny.

    PubMed

    Witt, T; Jürgens, A; Gottsberger, G

    2013-10-01

    Floral nectar composition has been explained as an adaptation to factors that are either directly or indirectly related to pollinator attraction. However, it is often unclear whether the sugar composition is a direct adaptation to pollinator preferences. Firstly, the lower osmolality of sucrose solutions means that they evaporate more rapidly than hexose solutions, which might be one reason why sucrose-rich nectar is typically found in flowers with long tubes (adapted to long-tongued pollinators), where it is better protected from evaporation than in open or short-tubed flowers. Secondly, it can be assumed that temperature-dependent evaporation is generally lower during the night than during the day so that selection pressure to secrete nectar with high osmolality (i.e. hexose-rich solutions) is relaxed for night-active flowers pollinated at night. Thirdly, the breeding system may affect selection pressure on nectar traits; that is, for pollinator-independent, self-pollinated plants, a lower selective pressure on nectar traits can be assumed, leading to a higher variability of nectar sugar composition independent of pollinator preferences, nectar accessibility and nectar protection. To analyse the relations between flower tube length, day vs. night pollination and self-pollination, the nectar sugar composition was investigated in 78 European Caryophylloideae (Caryophyllaceae) with different pollination modes (diurnal, nocturnal, self-pollination) using high-performance liquid chromatography (HPLC). All Caryophylleae species (Dianthus and relatives) were found to have nectar with more than 50% sucrose, whereas the sugar composition of Sileneae species (Silene and relatives) ranged from 0% to 98.2%. In the genus Silene, a clear dichotomous distribution of sucrose- and hexose-dominant nectars is evident. We found a positive correlation between the flower tube length and sucrose content in Caryophylloideae, particularly in day-flowering species, using both conventional analyses and phylogenetically independent contrasts. © 2013 The Authors. Journal of Evolutionary Biology © 2013 European Society For Evolutionary Biology.

  20. Thermally induced stresses and deformations in angle-ply composite tubes

    NASA Technical Reports Server (NTRS)

    Hyer, M. W.; Rousseau, Carl Q.

    1987-01-01

    Cure-induced uniform temperature change effects on the stresses, axial expansion, and thermally-induced twist of four specific angle-ply tube designs are discussed with a view to the tubes' use as major space structure components. The stresses and deformations in the tubes are studied as a function of the four designs, the off-axis angle, and the single-material and hybrid reinforcing-material construction used. It is found that tube design has a minor influence on the stresses, axial stiffness, and axial thermal expansion characteristics, which are more directly a function of off-axis angle and material selection; tube design is, however, the primary influence in the definition of thermally-induced twist and torsional stiffness characteristics. None of the designs is free of thermally induced twist.

  1. Influence of Alumina Reaction Tube Impurities on the Oxidation of Chemically-Vapor-Deposited Silicon Carbide

    NASA Technical Reports Server (NTRS)

    Opila, Elizabeth

    1995-01-01

    Pure coupons of chemically vapor deposited (CVD) SiC were oxidized for 100 h in dry flowing oxygen at 1300 C. The oxidation kinetics were monitored using thermogravimetry (TGA). The experiments were first performed using high-purity alumina reaction tubes. The experiments were then repeated using fused quartz reaction tubes. Differences in oxidation kinetics, scale composition, and scale morphology were observed. These differences were attributed to impurities in the alumina tubes. Investigators interested in high-temperature oxidation of silica formers should be aware that high-purity alumina can have significant effects on experiment results.

  2. Composite materials: A compilation

    NASA Technical Reports Server (NTRS)

    1976-01-01

    Design, analysis and fabrication techniques for boron-aluminum composite-structure technology is presented and a new method of joining different laminated composites without mechanical fasteners is proposed. Also discussed is a low-cost procedure for rigidifying expanded honeycomb tubing and piping simulations. A brief note on patent information is added.

  3. Joining Tubes With Adhesive

    NASA Technical Reports Server (NTRS)

    Bateman, W. A.

    1984-01-01

    Cylindrical tubes joined together, end to end, by method employing adhesive, tapered ends, and spacing wires. Tapered joint between tubular structural elements provides pressure between bonding surfaces during adhesive curing. Spacing wires prevent adhesive from being scraped away when one element inserted in other. Method developed for assembling structural elements made of composite materials.

  4. Development of underwater cutting system by abrasive water-jet

    NASA Astrophysics Data System (ADS)

    Demura, Kenji; Yamaguchi, Hitoshi

    1993-09-01

    The technology to cut objects in the ocean's depths with abrasive water jets was examined for possible application in view of the greater water depths and sophistication involved in work on the ocean floor today. A test model was developed to study this technology's safety and practicability. The test model was designed for use at great water depths and has functions and a configuration that are unlike equipment used on land. A continuous, stable supply of abrasive is a distinctive design feature. In land applications, there had been problems with plugged tubes and an uneven supply. For this reason, the abrasive was converted to slurry form, and a continuous pressurized tube pump system was adopted for supply to the nozzle head. Also, a hydraulic motor that does not employ oil or electric power was used to provide an underwater drive that is environment-friendly. The report outlines the technology's general design concept including its distinctive functions and its configuration for use at great depths, and the report provides great detail on the equipment.

  5. Foundation Elements for Naval Low-Rise Buildings

    DTIC Science & Technology

    2009-10-01

    of < 2% by total mass (oven dry weight) using a steam tube dryer . Wood flour, polymer, and lubricants were then mixed in a low intensity blender...Allendale, NJ) was employed for HDPE blends. Specific formulations for each composite are outlined in Table 1. A steam tube dryer was utilized to reduce...materials were weighed and dry-blended in 350lb batches prior to profile extrusion. The wood flour was first dried with a steam tube dryer to a moisture

  6. Cork Composites: A Review

    PubMed Central

    Gil, Luís

    2009-01-01

    Cork is a material which has been used for mankind for the last 5,000 years and it is a strategic material used for multiple applications, from wine bottles to aeronautics. Many of current cork materials are composites, in particular cork materials for floor and wall coverings and several other building and industrial applications. Recent developments in cork research have shifted from the classical cork-wine relationship to quality and environmental issues, exploitation of cork industry residues and new cork based materials. In recent years a number of new cork based composite materials were developed.

  7. Finite-Element Vibration Analysis and Modal Testing of Graphite Epoxy Tubes and Correlation Between the Data

    NASA Technical Reports Server (NTRS)

    Taleghani, Barmac K.; Pappa, Richard S.

    1996-01-01

    Structural materials in the form of graphite epoxy composites with embedded rubber layers are being used to reduce vibrations in rocket motor tubes. Four filament-wound, graphite epoxy tubes were studied to evaluate the effects of the rubber layer on the modal parameters (natural vibration frequencies, damping, and mode shapes). Tube 1 contained six alternating layers of 30-degree helical wraps and 90-degree hoop wraps. Tube 2 was identical to tube 1 with the addition of an embedded 0.030-inch-thick rubber layer. Tubes 3 and 4 were identical to tubes 1 and 2, respectively, with the addition of a Textron Kelpoxy elastomer. This report compares experimental modal parameters obtained by impact testing with analytical modal parameters obtained by NASTRAN finite-element analysis. Four test modes of tube 1 and five test modes of tube 3 correlate highly with corresponding analytical predictions. Unsatisfactory correlation of test and analysis results occurred for tubes 2 and 4 and these comparisons are not shown. Work is underway to improve the analytical models of these tubes. Test results clearly show that the embedded rubber layers significantly increase structural modal damping as well as decrease natural vibration frequencies.

  8. Self-sensing concrete-filled FRP tubes using FBG strain sensors

    NASA Astrophysics Data System (ADS)

    Yan, Xin; Li, Hui

    2007-07-01

    Concrete-filled fiber-reinforced polymer (FRP) tube is a type of newly developed structural column. It behaves brittle failure at its peak strength, and so the health monitoring on the hoop strain of the FRP tube is essential for the life cycle safety of the structure. Herein, three types of FRP tubes including 5-ply tube, 2-ply tube with local reinforcement and FRP-steel composite tube were embedded with the optic fiber Bragg grating (FBG) strain sensors in the inter-ply of FRP or the interface between FRP and steel in the middle height and the hoop direction. The compressive behaviors of the concrete-filled FRP tubes were experimentally studied. The hoop strains of the FRP tubes were recorded in real time using the embedded FBG strain sensors as well as the embedded or surface electric resistance strain gauges. Results indicated that the FBG strain sensors can faithfully record the hoop strains of the FRP tubes in compression as compared with the embedded or surface electric resistance strain gauges, and the strains recorded can reach more than μɛ.

  9. Development and fabrication of an advanced liquid cooling garment

    NASA Technical Reports Server (NTRS)

    Leith, J. R.; Hixon, C. W.

    1976-01-01

    The elastomeric film fin/tube concept which was developed is a composite of polyurethane film, fine expanded silver mesh, a serpentine pattern polyurethane transport tubing and an integral comfort liner, all bonded via adhesive application and vacuum-bagged for final cure. As demonstrated by thermal analysis, the composite garment material is capable of removing a 293 watt (1000 BTU/hr) metabolic load through a head and torso cooling area of .46 sq m (5 sq ft) with tube spacing of slightly under one inch. A total of 60 test elements, each .15m x .15m (6 in. x 6 in.) were fabricated in support of the liquid cooling garment concept development. In parallel with the fabrication of these elements a continuing series of laboratory tests to support the fabrication techniques was carried out. The elements and supporting tests are described.

  10. Pistons and Cylinders Made of Carbon-Carbon Composite Materials

    NASA Technical Reports Server (NTRS)

    Rivers, H. Kevin (Inventor); Ransone, Philip O. (Inventor); Northam, G. Burton (Inventor); Schwind, Francis A. (Inventor)

    2000-01-01

    An improved reciprocating internal combustion engine has a plurality of engine pistons, which are fabricated from carbon-carbon composite materials, in operative association with an engine cylinder block, or an engine cylinder tube, or an engine cylinder jug, all of which are also fabricated from carbon-carbon composite materials.

  11. Properties of dissolved and total organic matter in throughfall, stemflow and forest floor leachate of central European forests

    NASA Astrophysics Data System (ADS)

    Bischoff, S.; Schwarz, M. T.; Siemens, J.; Thieme, L.; Wilcke, W.; Michalzik, B.

    2015-05-01

    We present the first investigation of the composition of dissolved organic matter (DOM) compared to total organic matter (TOM, consisting of DOM, < 0.45 μm and particulate organic matter 0.45 μm < POM < 500 μm) in throughfall, stemflow and forest floor leachate of common beech (Fagus sylvatica L.) and Norway spruce (Picea abies (L.) H. Karst.) forests using solid-state 13C nuclear magnetic resonance (NMR) spectroscopy. We hypothesized that the composition and properties of organic matter (OM) in forest ecosystem water samples differ between DOM and TOM and between the two tree species. The 13C NMR results, derived from 21 samples, point to pronounced differences in the composition of DOM and TOM in throughfall solution at the beech sites, with TOM exhibiting higher relative intensities for the alkyl C region, which represents aliphatic C from less decomposed organic material compared to DOM. Furthermore, TOM shows lower intensities for lignin-derived and aromatic C of the aryl C region resulting in lower aromaticity indices and a diminished degree of humification. Across the ecosystem compartments, differences in the structural composition of DOM and TOM under beech lessened in the following order: throughfall > stemflow ≈ forest floor leachate. In contrast to the broadleaved sites, differences between DOM and TOM in throughfall solution under spruce were less pronounced and spectra were, overall, dominated by the alkyl C region, representing aliphatic C. Explanations of the reported results might be substantiated in differences in tree species-specific structural effects, leaching characteristics or differences in the microbial community of the tree species' phyllosphere and cortisphere. However, the fact that throughfall DOM under beech showed the highest intensities of recalcitrant aromatic and phenolic C among all samples analysed likely points to a high allelopathic potential of beech trees negatively affecting other organisms and hence ecosystem processes and functions.

  12. Quasi-static axial crushes on woven jute/polyester AA6063T52 composite tubes

    NASA Astrophysics Data System (ADS)

    Othman, A.; Ismail, AE

    2018-04-01

    Quasi-static axial loading have been studied in this paper to determine the behaviour of jute/polyester wrapped on aluminium alloy 6063T52. The filler material also was include into crush box specimen, which is polyurethane (PU) and polystyrene (PE) rigid foam at ranging 40 and 45 kg/m3 densities. All specimen profile was fabricated using hand layup techniques and the length of each specimen were fixed at 100 mm as well as diameter and width of the tube at 50.8 mm. The two types of tubular cross-section were studied of round and square thin-walled profiles and the angle of fibre at 450 were analysed for four layers. Thin walled of aluminium was 1.9 mm and end frontal of each specimen of composite were chamfered at 450 to prevent catastrophic failure mode. The specific absorbed energy (SEA) and crush force efficiency (CFE) were analyses for each specimen to see the behaviour on jute/polyester wrapped on metallic structure can give influence the energy management for automotive application. Result show that the four layers’ jute/polyester with filler material show significant value in term of specific absorbed energy compared empty and polyurethane profiles higher 26.66% for empty and 15.19% compared to polyurethane profiles. It has been found that the thin walled square profile of the jute/polyester tubes with polystyrene foam-filled is found higher respectively 27.42% to 13.13% than empty and polyurethane (PU) foam tubes. An introduce filler material onto thin walled composite profiles gave major advantage increases the mean axial load of 31.87% from 32.94 kN to 48.35 kN from empty to polystyrene thin walled round jute/polyester profiles and 31.7% from 23.11 KN to 33.84 kN from empty to polystyrene thin walled square jute/polyester profiles. Failure mechanisms of the axially loaded composite tubes were also observed and discussed.

  13. Branchfall as a Demographic Filter for Epiphyte Communities: Lessons from Forest Floor-Based Sampling

    PubMed Central

    Sarmento Cabral, Juliano; Petter, Gunnar; Mendieta-Leiva, Glenda; Wagner, Katrin; Zotz, Gerhard; Kreft, Holger

    2015-01-01

    Local variation in the abundance and richness of vascular epiphytes is often attributed to environmental characteristics such as substrate and microclimate. Less is known, however, about the impacts of tree and branch turnover on epiphyte communities. To address this issue, we surveyed branches and epiphytes found on the forest floor in 96 transects in two forests (Atlantic rainforest in Brazil and Caribbean rainforest in Panama). In the Brazilian forest, we additionally distinguished between edge and core study sites. We quantified branch abundance, epiphyte abundance, richness and proportion of adults to investigate the trends of these variables over branch diameter. Branches <2 cm in diameter comprised >90% of all branches on the forest floor. Abundance and richness of fallen epiphytes per transect were highest in the Brazilian core transects and lowest in the Panamanian transects. The majority of epiphytes on the floor (c. 65%) were found attached to branches. At all three study sites, branch abundance and branch diameter were negatively correlated, whereas epiphyte abundance and richness per branch, as well as the proportion of adults were positively correlated with branch diameter. The relationship between branch diameter and absolute epiphyte abundance or richness differed between study sites, which might be explained by differences in forest structure and dynamics. In the Panamanian forest, epiphytes had been previously inventoried, allowing an evaluation of our surveying method by comparing canopy and forest floor samplings. Individuals found on the forest floor corresponded to 13% of all individuals on branches <10 cm in diameter (including crowns), with abundance, richness and composition trends on forest floor reflecting canopy trends. We argue that forest floor surveys provide useful floristic and, most notably, demographic information particularly on epiphytes occurring on the thinnest branches, which are least accessible. Here, branchfall acts as an important demographic filter structuring epiphyte communities. PMID:26083417

  14. Spectral analysis of coniferous foliage and possible links to soil chemistry: are spectral chlorophyll indices related to forest floor dissolved organic C and N?

    PubMed

    Albrechtova, Jana; Seidl, Zdenek; Aitkenhead-Peterson, Jacqueline; Lhotáková, Zuzana; Rock, Barrett N; Alexander, Jess E; Malenovský, Zbynek; McDowell, William H

    2008-10-15

    Dissolved organic matter in soils can be predicted from forest floor C:N ratio, which in turn is related to foliar chemistry. Little is known about the linkages between foliar constituents such as chlorophylls, lignin, and cellulose and the concentrations of water-extractable forest floor dissolved organic carbon and dissolved organic nitrogen. Lignin and cellulose are not mobile in foliage and thus may be indicative of growing conditions during prior years, while chlorophylls respond more rapidly to the current physiological status of a tree and reflect nutrient availability. The aim of this study was to examine potential links among spectral foliar data, and the organic C and N of forest soils. Two coniferous species (red spruce and balsam fir) were studied in the White Mountains of New Hampshire, USA. Six trees of each species were sampled at 5 watersheds (2 in the Hubbard Brook Experimental Forest, 3 in the Bartlett Experimental Forest). We hypothesized that in a coniferous forest, chemistry of old foliage would better predict the chemical composition of the forest floor litter layer than younger foliage, which is the more physiologically active and the most likely to be captured by remote sensing of the canopy. Contrary to our expectations, chlorophyll concentration of young needles proved to be most tightly linked to soil properties, in particular water-extractable dissolved organic carbon. Spectral indices related to the chlorophyll content of needles could be used to predict variation in forest floor dissolved organic carbon and dissolved organic nitrogen. Strong correlations were found between optical spectral indices based on chlorophyll absorption and forest floor dissolved organic carbon, with higher foliage chlorophyll content corresponding to lower forest floor dissolved organic carbon. The mechanisms behind these correlations are uncertain and need further investigation. However, the direction of the linkage from soil to tree via nutrient availability is hypothesized based on negative correlations found between foliar N and forest floor dissolved organic carbon.

  15. Mechanism of deposit formation on fuel-wetted metal surfaces

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Stavinoha, L.L.; Westbrook, S.R.; McInnis, L.A.

    1995-05-01

    Experiments were performed in a Single-Tube Heat Exchanger (STHE) apparatus and a Hot Liquid Process Simulator (HLPS) configured and operated to meet Jet Fuel Thermal Oxidation Tester (JFTOT) ASTM D 3241 requirements. The HLPS-JFTOT heater tubes used were 1018 mild steel, 316 stainless steel (SS), 304 stainless steel (SS), and 304 SS tubes coated with aluminum, magnesium, gold, and copper. A low-sulfur Jet A fuel with a breakpoint temperature of 254{degrees}C was used to create deposits on the heater tubes at temperatures of 300{degrees}C, 340{degrees}C, and 380{degrees}C. Deposit thickness was measured by dielectric breakdown voltage and Auger ion milling. Pronouncedmore » differences between the deposit thickness measuring techniques suggested that both the Auger milling rate and the dielectric strength of the deposit may be affected by deposit morphology/composition (such as metal ions that may have become included in the bulk of the deposit). Carbon burnoff data were obtained as a means of judging the validity of DMD-derived deposit evaluations. ESCA data suggest that the thinnest deposit was on the magnesium-coated test tube. The Scanning Electron Microscope (SEM) photographs showed marked variations in the deposit morphology and the results suggested that surface composition has a significant effect on the mechanism of deposition. The most dramatic effect observed was that the bulk of deposits moved to tube locations of lower temperature as the maximum temperature of the tube was increased from 300{degrees} to 380{degrees}C, also verified in a single-tube heat exchanger. The results indicate that the deposition rate and quantity at elevated temperatures is not completely temperature dependent, but is limited by the concentration of dissolved oxygen and/or reactive components in the fuel over a temperature range.« less

  16. In Vitro Evaluation of Eslicarbazepine Delivery via Enteral Feeding Tubes.

    PubMed

    Reindel, Kristin; Zhao, Fang; Hughes, Susan; Dave, Vivek S

    2017-12-01

    Purpose: The feasibility of preparing an eslicarbazepine acetate suspension using Aptiom tablets for administration via enteral feeding tubes was evaluated. Methods: Eslicarbazepine acetate suspension (40 mg/mL) was prepared using Aptiom tablets after optimizing the tablet crushing methods and the vehicle composition. A stability-indicating high-performance liquid chromatography (HPLC) method was developed to monitor the eslicarbazepine stability in the prepared suspension. Three enteric feeding tubes of various composition and dimensions were evaluated for the delivery of the suspensions. The suspension was evaluated for the physical and chemical stability for 48 hours. Results: The reproducibility and consistency of particle size reduction was found to be best with standard mortar/pestle. The viscosity analysis and physical stability studies showed that ORA-Plus:water (50:50 v/v) was optimal for suspending ability and flowability of suspension through the tubes. The developed HPLC method was found to be stability indicating and suitable for the assay of eslicarbazepine acetate in the prepared suspension. The eslicarbazepine concentrations in separately prepared suspensions were within acceptable range (±3%), indicating accuracy and reproducibility of the procedure. The eslicarbazepine concentrations in suspensions before and after delivery through the enteric feeding tubes were within acceptable range (±4%), indicating absence of any physical/chemical interactions of eslicarbazepine with the tubes and a successful delivery of eslicarbazepine dosage via enteric feeding tubes. The stability study results showed that eslicarbazepine concentration in the suspension remained unchanged when stored at room temperature for 48 hours. Conclusion: The study presents a convenient procedure for the preparation of a stable suspension of eslicarbazepine acetate (40 mg/mL) using Aptiom tablets, for administration via enteral feeding tubes.

  17. CELL SEGREGATION, MIXING, AND TISSUE PATTERN IN THE SPINAL CORD OF THE XENOPUS LAEVIS NEURULA

    PubMed Central

    Davidson, Lance A.; Keller, Raymond E.

    2014-01-01

    Background During Xenopus laevis neurulation, neural ectodermal cells of the spinal cord are patterned at the same time that they intercalate mediolaterally and radially, moving within and between two cell layers. Curious if these rearrangements disrupt early cell identities, we lineage-traced cells in each layer from neural plate stages to the closed neural tube, and used in situ hybridization to assay gene expression in the moving cells. Results Our biotin- and fluorescent labeling of deep and superficial cells reveals that mediolateral intercalation does not disrupt cell cohorts, in other words it is conservative. However, outside the midline notoplate, later radial intercalation does displace superficial cells dorsoventrally, radically disrupting cell cohorts. The tube roof is composed almost exclusively of superficial cells, including some displaced from ventral positions; gene expression in these displaced cells must now be surveyed further. Superficial cells also flank the tube’s floor, which is, itself, almost exclusively composed of deep cells. Conclusions Our data provide: 1) a fate map of superficial- and deep-cell positions within the Xenopus neural tube, 2) the paths taken to these positions, and 3) preliminary evidence of re-patterning in cells carried out of one environment and into another, during neural morphogenesis. PMID:23813905

  18. The propagation characteristics of the plate modes of acoustic emission waves in thin aluminum plates and thin graphite/epoxy composite plates and tubes. Ph.D. Thesis - Johns Hopkins Univ., 1991

    NASA Technical Reports Server (NTRS)

    Prosser, William H.

    1991-01-01

    Acoustic emission was interpreted as modes of vibration in plates. Classical plate theory was used to predict dispersion curves for the two fundamental modes and to calculate the shapes of flexural waveforms produced by vertical step function loading. There was good agreement between theoretical and experimental results for aluminum. Composite materials required the use of a higher order plate theory (Reissner-Mindlin) to get good agreement with the measured velocities. Four composite plates with different laminate stacking sequences were studied. The dispersion curves were determined from phase spectra of the time dependent waveforms. Plate modes were shown to be useful for determining the direction of source motion. Aluminum plates were loaded by breaking a pencil lead against their surface. By machining slots at angles to the plane of a plate, the direction in which the force acted was varied. Changing the source motion direction produced regular variations in the waveforms. To demonstrate applicability beyond simple plates, waveforms produced by lead breaks on a thin walled composite tube were also shown to be interpretable as plate modes. The tube design was based on the type of struts proposed for Space Station Freedom's trussed structures.

  19. Basalt depths in lunar basins using impact craters as stratigraphic probes: Evaluation of a method using orbital geochemical data

    NASA Technical Reports Server (NTRS)

    Andre, C. G.

    1986-01-01

    A rare look at the chemical composition of subsurface stratigraphy in lunar basins filled with mare basalt is possible at fresh impact craters. Mg/Al maps from orbital X-ray flourescence measurements of mare areas indicate chemical anomalies associated with materials ejected by large post-mare impacts. A method of constraining the wide-ranging estimates of mare basalt depths using the orbital MG/Al data is evaluated and the results are compared to those of investigators using different indirect methods. Chemical anomalies at impact craters within the maria indicate five locations where higher Mg/Al basalt compositions may have been excavated from beneath the surface layer. At eight other locations, low Mg/Al anomalies suggest that basin-floor material was ejected. In these two cases, the stratigraphic layers are interpreted to occur at depths less than the calculated maximum depth of excavation. In five other cases, there is no apparent chemical change between the crater and the surrounding mare surface. This suggests homogeneous basalt compositions that extend down to the depths sampled, i.e., no anorthositic material that might represent the basin floor was exposed.

  20. Simulation of an Impact Test of the All-Composite Lear Fan Aircraft

    NASA Technical Reports Server (NTRS)

    Stockwell, Alan E.; Jones, Lisa E. (Technical Monitor)

    2002-01-01

    An MSC.Dytran model of an all-composite Lear Fan aircraft fuselage was developed to simulate an impact test conducted at the NASA Langley Research Center Impact Dynamics Research Facility (IDRF). The test was the second of two Lear Fan impact tests. The purpose of the second test was to evaluate the performance of retrofitted composite energy-absorbing floor beams. A computerized photogrammetric survey was performed to provide airframe geometric coordinates, and over 5000 points were processed and imported into MSC.Patran via an IGES file. MSC.Patran was then used to develop the curves and surfaces and to mesh the finite element model. A model of the energy-absorbing floor beams was developed separately and then integrated into the Lear Fan model. Structural responses of components such as the wings were compared with experimental data or previously published analytical data wherever possible. Comparisons with experimental results were used to guide structural model modifications to improve the simulation performance. This process was based largely on qualitative (video and still camera images and post-test inspections) rather than quantitative results due to the relatively few accelerometers attached to the structure.

  1. Housing Systems Influence Gut Microbiota Composition of Sows but Not of Their Piglets.

    PubMed

    Kubasova, Tereza; Davidova-Gerzova, Lenka; Merlot, Elodie; Medvecky, Matej; Polansky, Ondrej; Gardan-Salmon, Delphine; Quesnel, Helene; Rychlik, Ivan

    2017-01-01

    Different housing systems can be used in pig production and little is known about their effect on gut microbiota composition. In this study we characterized fecal microbiota by sequencing the rRNA genes in sows kept during gestation in conventional pens with a slatted floor and in enriched pens with a floor covered with deep straw. After farrowing, microbiota of 1- and 4-day-old piglets were also monitored. Microbiota of sows from the enriched system contained significantly more Prevotella, Parabacteroides, CF231, Phascolarctobacterium, Fibrobacter, Anaerovibrio and YRC22 and significantly less Lactobacillus, Bulleidia, Lachnospira, Dorea, Ruminococcus and Oscillospira than microbiota of sows from the conventional system. The Firmicutes to Bacteroidetes ratio was 0.96 in the microbiota of sows kept in the enriched pens and this increased to 1.66 in the microbiota of sows kept in the conventional system. The production system therefore influenced microbiota composition, most likely due the ingestion of the straw. The microbiota of 1- and 4-day-old piglets differed from the microbiota of sows and sows therefore did not represent the most important source for their colonization in early days of life.

  2. Housing Systems Influence Gut Microbiota Composition of Sows but Not of Their Piglets

    PubMed Central

    Kubasova, Tereza; Davidova-Gerzova, Lenka; Merlot, Elodie; Medvecky, Matej; Polansky, Ondrej; Gardan-Salmon, Delphine; Quesnel, Helene; Rychlik, Ivan

    2017-01-01

    Different housing systems can be used in pig production and little is known about their effect on gut microbiota composition. In this study we characterized fecal microbiota by sequencing the rRNA genes in sows kept during gestation in conventional pens with a slatted floor and in enriched pens with a floor covered with deep straw. After farrowing, microbiota of 1- and 4-day-old piglets were also monitored. Microbiota of sows from the enriched system contained significantly more Prevotella, Parabacteroides, CF231, Phascolarctobacterium, Fibrobacter, Anaerovibrio and YRC22 and significantly less Lactobacillus, Bulleidia, Lachnospira, Dorea, Ruminococcus and Oscillospira than microbiota of sows from the conventional system. The Firmicutes to Bacteroidetes ratio was 0.96 in the microbiota of sows kept in the enriched pens and this increased to 1.66 in the microbiota of sows kept in the conventional system. The production system therefore influenced microbiota composition, most likely due the ingestion of the straw. The microbiota of 1- and 4-day-old piglets differed from the microbiota of sows and sows therefore did not represent the most important source for their colonization in early days of life. PMID:28085934

  3. The Loss Cone Imager (LCI)

    DTIC Science & Technology

    2006-07-24

    at this time that the PMO provided the current LCI configuration (integrated DPU/HST on the PM, the RSH units on a composite tube , later to become...approximated by parallel planes of 1000 A of aluminum on a 0.5 mil mylar foil in front of a 1000 tim (or 1500 tim) silicon detector, detector A...above manufacturers form these alloys in tube form. In order to produce a tube , a rod would be formed and then a hold bored through the center. Some of

  4. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hesse, Cedar N.; Mueller, Rebecca C.; Vuyisich, Momchilo

    Anthropogenic N deposition alters patterns of C and N cycling in temperate forests, where forest floor litter decomposition is a key process mediated by a diverse community of bacteria and fungi. To track forest floor decomposer activity we generated metatranscriptomes that simultaneously surveyed the actively expressed bacterial and eukaryote genes in the forest floor, to compare the impact of N deposition on the decomposers in two natural maple forests in Michigan, USA, where replicate field plots had been amended with N for 16 years. Site and N amendment responses were compared using about 74,000 carbohydrate active enzyme transcript sequences (CAZymes)more » in each metatranscriptome. Parallel ribosomal RNA (rRNA) surveys of bacterial and fungal biomass and taxonomic composition showed no significant differences in either biomass or OTU richness between the two sites or in response to N. Site and N amendment were not significant variables defining bacterial taxonomic composition, but they were significant for fungal community composition, explaining 17 and 14% of the variability, respectively. The relative abundance of expressed bacterial and fungal CAZymes changed significantly with N amendment in one of the forests, and N-response trends were also identified in the second forest. Although the two ambient forests were similar in community biomass, taxonomic structure and active CAZyme profile, the shifts in active CAZyme profiles in response to N-amendment differed between the sites. One site responded with an over-expression of bacterial CAZymes, and the other site responded with an over-expression of both fungal and different bacterial CAZymes. Both sites showed reduced representation of fungal lignocellulose degrading enzymes in N-amendment plots. The metatranscriptome approach provided a holistic assessment of eukaryote and bacterial gene expression and is applicable to other systems where eukaryotes and bacteria interact.« less

  5. Durable hydrophobic coating composition for metallic surfaces and method for the preparation of the composition

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Liu, Jiong

    A durable hydrophobic coating composition containing fluorinated silanes for metallic surfaces, such as stainless steel surfaces. The composition includes at least one fluorine-containing silane compound, at least one phosphorus-containing silane compound, and at least one hydrolysable compound. This coating is suitable for condenser tubes, among other applications, to promote dropwise condensation.

  6. Cooperative program for design, fabrication, and testing of graphite/epoxy composite helicopter shafting

    NASA Technical Reports Server (NTRS)

    Wright, C. C.; Baker, D. J.; Corvelli, N.; Thurston, L.; Clary, R.; Illg, W.

    1971-01-01

    The fabrication of UH-1 helicopter tail rotor drive shafts from graphite/epoxy composite materials is discussed. Procedures for eliminating wrinkles caused by lack of precure compaction are described. The development of the adhesive bond between aluminum end couplings and the composite tube is analyzed. Performance tests to validate the superiority of the composite materials are reported.

  7. Composite propulsion feedlines for cryogenic space vehicles, volume 1

    NASA Technical Reports Server (NTRS)

    Hall, C. A.; Laintz, D. J.; Phillips, J. M.

    1973-01-01

    Thin metallic liners that provide leak-free service in cryogenic propulsion systems are overwrapped with a glass-fiber composite that provides strength and protection from handling damage. The resultant tube is lightweight, strong and has a very low thermal flux. Several styles of tubing ranging from 5 to 38 cm in diameter and up to 305 cm long were fabricated and tested at operating temperatures from 294 to 21 K and operating pressures up to 259 N/sq cm. The primary objective for the smaller sizes was thermal performance optimization of the propulsion system while the primary objective of the larger sizes was weight optimization and to prove fabricability. All major program objectives were met resulting in a design concept that is adaptable to a wide range of aerospace vehicle requirements. Major items of development included: bonding large diameter aluminum end fittings to the thin Inconel liner; fabrication of a 38 cm diameter tube from 0.008 cm thick Inconel; and evaluation of tubing which provides essentially zero quality propellant in a very short period of time resulting in a lower mass of propellant expended in chilldown.

  8. Stresses and deformations in cross-ply composite tubes subjected to a uniform temperature change: Elasticity and Approximate Solutions

    NASA Technical Reports Server (NTRS)

    Hyer, M. W.; Cooper, D. E.; Cohen, D.

    1985-01-01

    The effects of a uniform temperature change on the stresses and deformations of composite tubes are investigated. The accuracy of an approximate solution based on the principle of complementary virtual work is determined. Interest centers on tube response away from the ends and so a planar elasticity approach is used. For the approximate solution a piecewise linear variation of stresses with the radial coordinate is assumed. The results from the approximate solution are compared with the elasticity solution. The stress predictions agree well, particularly peak interlaminar stresses. Surprisingly, the axial deformations also agree well. This, despite the fact that the deformations predicted by the approximate solution do not satisfy the interface displacement continuity conditions required by the elasticity solution. The study shows that the axial thermal expansion coefficient of tubes with a specific number of axial and circumferential layers depends on the stacking sequence. This is in contrast to classical lamination theory which predicts the expansion to be independent of the stacking arrangement. As expected, the sign and magnitude of the peak interlaminar stresses depends on stacking sequence.

  9. Specific Adaptation of Gas Atomization Processing for Al-Based Alloy Powder for Additive Manufacturing

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Anderson, Iver; Siemon, John

    The initial three atomization attempts resulted in “freeze-outs” within the pour tubes in the pilot-scale system and yielded no powder. Re-evaluation of the alloy liquidus temperatures and melting characteristics, in collaboration with Alcoa, showed further superheat to be necessary to allow the liquid metal to flow through the pour tube to the atomization nozzle. A subsequent smaller run on the experimental atomization system verified these parameters and was successful, as were all successive runs on the larger pilot scale system. One alloy composition froze-out part way through the atomization on both pilot scale runs. SEM images showed needle formation andmore » phase segregations within the microstructure. Analysis of the pour tube freeze-out microstructures showed that large needles formed within the pour tube during the atomization experiment, which eventually blocked the melt stream. Alcoa verified the needle formation in this alloy using theoretical modeling of phase solidification. Sufficient powder of this composition was still generated to allow powder characterization and additive manufacturing trials at Alcoa.« less

  10. Micro-tube biotemplate synthesis of Fe3O4/C composite as anode material for lithium-ion batteries

    NASA Astrophysics Data System (ADS)

    Du, Jun; Ding, Yu; Guo, Liangui; Wang, Li; Fu, Zhengbing; Qin, Caiqin; Wang, Feng; Tao, Xinyong

    2017-12-01

    Kapok fibres were used as micro-tube biotemplate and bio-carbon source to synthesise Fe3O4/C composites, which were then utilised as anode materials. Fe3O4 nanoparticles were grown uniformly onto the external surface and internal channel of kapok carbon fibres. The flexibility, high specific surface area and electronic conduction of kapok fibres can buffer the volume expansion as well as inhibit the aggregation of Fe3O4 nanoparticles. Thus, the electrical integrity and structural of the Fe3O4/C composites electrode during lithiation/delithiation processes. The Fe3O4/C composites electrode delivers a high reversible capacity of 596 mA h g-1 after 100 cycles and an ultra-high coulombic efficiency approaching 100%. The high electrochemical performance of the Fe3O4/C composites can be caused by the synergistic effect of the Fe3O4 nanoparticles and the structure of kapok carbon fibres.

  11. Investigation of CNTD Silicon Nitride on Complex Shapes.

    DTIC Science & Technology

    1980-02-06

    tubing) ! NH 3 + H 2 + N 2 SiCl4 + N2 Chamber Pressure, 4 2 To Manometer (copper tubing) t8 2 A: 2" DIA or 0 0 " To Pumping System _____________Pt/Pt-l3Rh...Total Gas Flow Rate: 47,350 cm3/min Gas Composition: N2 = 25,000 ml/min H2 = 20,600 ml/min Ar = 700 ml/min NH3 = 650 ml/min SiCl4 = 400 ml/min The...Values for SiCl4 were not available. In addition, the fractions of these two gases are extremely small in the overall gas composition. Individual

  12. Thermal stresses in composite tubes using complementary virtual work

    NASA Technical Reports Server (NTRS)

    Hyer, M. W.; Cooper, D. E.

    1988-01-01

    This paper addresses the computation of thermally induced stresses in layered, fiber-reinforced composite tubes subjected to a circumferential gradient. The paper focuses on using the principle of complementary virtual work, in conjunction with a Ritz approximation to the stress field, to study the influence on the predicted stresses of including temperature-dependent material properties. Results indicate that the computed values of stress are sensitive to the temperature dependence of the matrix-direction compliance and matrix-direction thermal expansion in the plane of the lamina. There is less sensitivity to the temperature dependence of the other material properties.

  13. Sea-Floor geology and character of Eastern Rhode Island Sound West of Gay Head, Massachusetts

    USGS Publications Warehouse

    Poppe, L.J.; McMullen, K.Y.; Ackerman, S.D.; Blackwood, D.S.; Irwin, B.J.; Schaer, J.D.; Forrest, M.R.

    2011-01-01

    Gridded multibeam bathymetry covers approximately 102 square kilometers of sea floor in eastern Rhode Island Sound west of Gay Head, Massachusetts. Although originally collected for charting purposes during National Oceanic and Atmospheric Administration hydrographic survey H11922, these acoustic data and the sea-floor stations subsequently occupied to verify them (1) show the composition and terrain of the seabed, (2) provide information on sediment transport and benthic habitat, and (3) are part of an expanding series of studies that provide a fundamental framework for research and management activities (for example, windfarms and fisheries) along the Massachusetts inner continental shelf. Most of the sea floor in the study area has an undulating to faintly rippled appearance and is composed of bioturbated muddy sand, reflecting processes associated with sediment sorting and reworking. Shallower areas are composed of rippled sand and, where small fields of megaripples are present, indicate sedimentary environments characterized by processes associated with coarse bedload transport. Boulders and gravel were found on the floors of scour depressions and on top of an isolated bathymetric high where erosion has removed the Holocene marine sediments and exposed the underlying relict lag deposits of Pleistocene drift. The numerous scour depressions, which formed during storm-driven events, result in the juxtaposition of sea-floor areas with contrasting sedimentary environments and distinct gravel, sand, and muddy sand textures. This textural heterogeneity in turn creates a complex patchwork of habitats. Our observations of local variations in community structure suggest that this small-scale textural heterogeneity adds dramatically to the sound-wide benthic biological diversity.

  14. Graphite Fiber Textile Preform/Cooper Matrix Composites

    NASA Technical Reports Server (NTRS)

    Filatovs, George J.

    1998-01-01

    The purpose of this research was to produce a finned tube constructed of a highly conductive braided graphite fiber preform infiltrated with a copper matrix. In addition, the tube was to be fabricated with an integral geometry. The preform was integral in the sense that the tube and the fin could be braided to yield one continuous part. This composite component is a candidate for situations with high heat transmitting and radiation requirements. A proof-of-concept finned tube was braided and infiltrated with a copper matrix proving that a viable process was developed to fabricate the desired component. Braiding of high conductivity carbon fibers required much trial-and-error and development of special procedures. There are many tradeoffs between braidability and fiber conductivity. To understand the properties and structure of the braided finned tube, an geometric model of the braid structure was derived. This derivation set the basis for the research because knowing the tow orientations helped decipher the thermal as well as the mechanical and conduction tendencies. Infiltration of the fibers into a copper matrix was a complex procedure, and was performed by TRA, of Salt Lake City, Utah, using a proprietary process. Several batches were fabricated with a final, high quality batch serving as a confirming proof-of-concept.

  15. Platinum atomic wire encapsulated in gold nanotubes: A first principle study

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Nigam, Sandeep, E-mail: snigam@barc.gov.in; Majumder, Chiranjib; Sahoo, Suman K.

    2014-04-24

    The nanotubes of gold incorporated with platinum atomic wire have been investigated by means of firstprinciples density functional theory with plane wave pseudopotential approximation. The structure with zig-zag chain of Pt atoms in side gold is found to be 0.73 eV lower in energy in comparison to straight chain of platinum atoms. The Fermi level of the composite tube was consisting of d-orbitals of Pt atoms. Further interaction of oxygen with these tubes reveals that while tube with zig-zag Pt prefers dissociative adsorption of oxygen molecule, the gold tube with linear Pt wire favors molecular adsorption.

  16. Lightweight composites for modular panelized construction

    NASA Astrophysics Data System (ADS)

    Vaidya, Amol S.

    Rapid advances in construction materials technology have enabled civil engineers to achieve impressive gains in the safety, economy, and functionality of structures built to serve the common needs of society. Modular building systems is a fast-growing modern, form of construction gaining recognition for its increased efficiency and ability to apply modern technology to the needs of the market place. In the modular construction technique, a single structural panel can perform a number of functions such as providing thermal insulation, vibration damping, and structural strength. These multifunctional panels can be prefabricated in a manufacturing facility and then transferred to the construction site. A system that uses prefabricated panels for construction is called a "panelized construction system". This study focuses on the development of pre-cast, lightweight, multifunctional sandwich composite panels to be used for panelized construction. Two thermoplastic composite panels are proposed in this study, namely Composite Structural Insulated Panels (CSIPs) for exterior walls, floors and roofs, and Open Core Sandwich composite for multifunctional interior walls of a structure. Special manufacturing techniques are developed for manufacturing these panels. The structural behavior of these panels is analyzed based on various building design codes. Detailed descriptions of the design, cost analysis, manufacturing, finite element modeling and structural testing of these proposed panels are included in this study in the of form five peer-reviewed journal articles. The structural testing of the proposed panels involved in this study included flexural testing, axial compression testing, and low and high velocity impact testing. Based on the current study, the proposed CSIP wall and floor panels were found satisfactory, based on building design codes ASCE-7-05 and ACI-318-05. Joining techniques are proposed in this study for connecting the precast panels on the construction site. Keywords: Modular panelized construction, sandwich composites, composite structural insulated panels (CSIPs).

  17. Hard Facts.

    ERIC Educational Resources Information Center

    Shaw, Richard

    1998-01-01

    Discusses the selection of floor-care equipment so that the equipment's features and performance attributes can match their intended purposes. Offers tips such as buying only composite-material buckets and wringers, choosing cleaning machines with good maintenance track records, and buying automatic scrubbers that can operate in both large and…

  18. Shielding Design for the South Pole nToF Diagnostic at the NIF

    NASA Astrophysics Data System (ADS)

    Khater, Hesham; Sitaraman, Shiva; Hall, James; Hatarik, Robert; Caggiano, Joseph; Waltz, Cory

    2017-09-01

    Neutron time of flight (nToF) detectors are fielded at the National Ignition Facility (NIF) to measure neutron yield, ion temperature, and downscattering in the cold fuel for D-T implosions. Anisotropically assembled cold fuel may generate different nToF data when measured by detectors located at the Target Chamber equator and poles. A collimated nToF line of sight has been fielded near the Target Chamber South Pole (SP) to examine any possible anisotropy in the cold fuel. The SP nToF detector is located in the lowest floor level of the NIF's Target Bay and at a distance of 18 m from the Target Chamber Center. The detector utilizes a solid bibenzyl scintillator and four photomultiplier tubes. The line of sight includes a port collimator that is attached to the Target Chamber and a bore hole collimator in the concrete floor above the detector. In addition, a beam line get lost hole is constructed in the Target Bay floor to minimize the backscattered radiation at the detector location. Initial measurements indicated the need for installation of additional shielding to eliminate gamma background during the period before arrival of the 14.1 MeV neutrons to the detector. A set of MCNP Monte Carlo simulations with the full Target Bay model were conducted to provide an estimate of the expected neutron and gamma backgrounds during D-T shots. A new shielding scheme is designed to reduce the gamma background by an order of magnitude.

  19. A spinal cord fate map in the avian embryo: while regressing, Hensen's node lays down the notochord and floor plate thus joining the spinal cord lateral walls.

    PubMed

    Catala, M; Teillet, M A; De Robertis, E M; Le Douarin, M L

    1996-09-01

    The spinal cord of thoracic, lumbar and caudal levels is derived from a region designated as the sinus rhomboidalis in the 6-somite-stage embryo. Using quail/chick grafts performed in ovo, we show the following. (1) The floor plate and notochord derive from a common population of cells, located in Hensen's node, which is equivalent to the chordoneural hinge (CNH) as it was defined at the tail bud stage. (2) The lateral walls and the roof of the neural tube originate caudally and laterally to Hensen's node, during the regression of which the basal plate anlage is bisected by floor plate tissue. (3) Primary and secondary neurulations involve similar morphogenetic movements but, in contrast to primary neurulation, extensive bilateral cell mixing is observed on the dorsal side of the region of secondary neurulation. (4) The posterior midline of the sinus rhomboidalis gives rise to somitic mesoderm and not to spinal cord. Moreover, mesodermal progenitors are spatially arranged along the rest of the primitive streak, more caudal cells giving rise to more lateral embryonic structures. Together with the results reported in our study of tail bud development (Catala, M., Teillet, M.-A. and Le Douarin, N.M. (1995). Mech. Dev. 51, 51-65), these results show that the mechanisms that preside at axial elongation from the 6-somite stage onwards are fundamentally similar during the complete process of neurulation.

  20. Monitoring of Bio-signal of People on Flooring, Tatami and in Bathtub, Toilet

    NASA Astrophysics Data System (ADS)

    Kurihara, Yosuke; Kawanishi, Yoshihiro; Watanabe, Kajiro; Kobayashi, Kazuyuki; Tanaka, Hiroshi

    In the graying Japanese society, monitoring health-related human data with sensors embedded in the living environment is quite meaningful in terms of emergency response and of long-term health management. In using the body data monitoring system daily at home, the lack of invasiveness during the monitoring and the maintenance of the system are of great importance. We have proposed the method to surmise the sleep stages of sleeping subjects by measuring the heartbeats and the respirations without invasiveness using the pneumatic method with an air mattress. This method, however, has a problem in the maintenance, since it requires periodic refilling of the air into the mattress. In this paper, another pneumatic method, which applies silicon tubes instead of the air mattress, is proposed. The change of S/N ratio in heartbeat and respiration signals, while having the environmental noises increased, are compared among a room with wooden flooring, another with tatami mats, a bath tub, and a toilet room. The result shows that both the pulse waves and the breaths can be measured with the accuracy of around 30dB, and the identification of each pulse from among the pulse waves is also feasible, under the condition that the environmental noises in the room with wooden flooring, that with tatami mats, the bath tub, and the rest room are 0.01G, 0.09G, 100ml, and 0.01G respectively.

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