Sample records for contract types sealed

  1. 48 CFR 14.101 - Elements of sealed bidding.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 1 2013-10-01 2013-10-01 false Elements of sealed bidding. 14.101 Section 14.101 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Use of Sealed Bidding 14.101 Elements of sealed bidding...

  2. 48 CFR 14.101 - Elements of sealed bidding.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 1 2014-10-01 2014-10-01 false Elements of sealed bidding. 14.101 Section 14.101 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Use of Sealed Bidding 14.101 Elements of sealed bidding...

  3. 48 CFR 14.101 - Elements of sealed bidding.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 1 2011-10-01 2011-10-01 false Elements of sealed bidding. 14.101 Section 14.101 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Use of Sealed Bidding 14.101 Elements of sealed bidding...

  4. 48 CFR 14.101 - Elements of sealed bidding.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Elements of sealed bidding. 14.101 Section 14.101 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Use of Sealed Bidding 14.101 Elements of sealed bidding...

  5. 48 CFR 14.101 - Elements of sealed bidding.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 1 2012-10-01 2012-10-01 false Elements of sealed bidding. 14.101 Section 14.101 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Use of Sealed Bidding 14.101 Elements of sealed bidding...

  6. 48 CFR 16.102 - Policies.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Policies. 16.102 Section... CONTRACT TYPES TYPES OF CONTRACTS Selecting Contract Types 16.102 Policies. (a) Contracts resulting from sealed bidding shall be firm-fixed-price contracts or fixed-price contracts with economic price...

  7. 48 CFR 14.103 - Policy.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 1 2013-10-01 2013-10-01 false Policy. 14.103 Section 14.103 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Use of Sealed Bidding 14.103 Policy. ...

  8. 48 CFR 14.401 - Receipt and safeguarding of bids.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Opening of Bids and Award of Contract 14.401 Receipt and... identification, and then only by an official designated for this purpose. If a sealed bid is opened by mistake (e.g., because it is not marked as being a bid), the envelope shall be signed by the opener, whose...

  9. 48 CFR 314.103 - Policy.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... CONTRACT TYPES SEALED BIDDING Use of Sealed Bidding 314.103 Policy. EIT products and services, including EIT deliverables such as electronic documents and reports, acquired using sealed-bid procedures shall... determinations for EIT products and services that do not meet some or all of the applicable Section 508...

  10. 48 CFR 14.407-2 - Apparent clerical mistakes.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Opening of Bids and Award of Contract 14.407-2 Apparent... contracting officer before award. The contracting officer first shall obtain from the bidder a verification of the bid intended. Examples of apparent mistakes are— (1) Obvious misplacement of a decimal point; (2...

  11. 48 CFR 14.407-2 - Apparent clerical mistakes.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Opening of Bids and Award of Contract 14.407-2 Apparent... contracting officer before award. The contracting officer first shall obtain from the bidder a verification of the bid intended. Examples of apparent mistakes are— (1) Obvious misplacement of a decimal point; (2...

  12. 48 CFR 14.407-4 - Mistakes after award.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Opening of Bids and Award of Contract 14.407-4 Mistakes...) To rescind a contract; (2) To reform a contract (i) to delete the items involved in the mistake or.... (vi) A written request by the contractor to reform or rescind the contract, and copies of all other...

  13. 48 CFR 14.407-4 - Mistakes after award.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Opening of Bids and Award of Contract 14.407-4 Mistakes...) To rescind a contract; (2) To reform a contract (i) to delete the items involved in the mistake or.... (vi) A written request by the contractor to reform or rescind the contract, and copies of all other...

  14. 48 CFR 14.407-4 - Mistakes after award.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Opening of Bids and Award of Contract 14.407-4 Mistakes...) To rescind a contract; (2) To reform a contract (i) to delete the items involved in the mistake or.... (vi) A written request by the contractor to reform or rescind the contract, and copies of all other...

  15. 48 CFR 14.407-4 - Mistakes after award.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Opening of Bids and Award of Contract 14.407-4 Mistakes...) To rescind a contract; (2) To reform a contract (i) to delete the items involved in the mistake or.... (vi) A written request by the contractor to reform or rescind the contract, and copies of all other...

  16. 48 CFR 14.407-4 - Mistakes after award.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Opening of Bids and Award of Contract 14.407-4 Mistakes...) To rescind a contract; (2) To reform a contract (i) to delete the items involved in the mistake or.... (vi) A written request by the contractor to reform or rescind the contract, and copies of all other...

  17. 48 CFR 14.503-2 - Step two.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Step two. 14.503-2 Section... AND CONTRACT TYPES SEALED BIDDING Two-Step Sealed Bidding 14.503-2 Step two. (a) Sealed bidding... submitting acceptable technical proposals in step one; (2) Include the provision prescribed in 14.201-6(t...

  18. 48 CFR 14.212 - Economic purchase quantities (supplies).

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Economic purchase... REGULATION CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Solicitation of Bids 14.212 Economic purchase quantities (supplies). Contracting officers shall comply with the economic purchase quantity...

  19. 48 CFR 14.212 - Economic purchase quantities (supplies).

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 1 2012-10-01 2012-10-01 false Economic purchase... REGULATION CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Solicitation of Bids 14.212 Economic purchase quantities (supplies). Contracting officers shall comply with the economic purchase quantity...

  20. 48 CFR 14.212 - Economic purchase quantities (supplies).

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 1 2013-10-01 2013-10-01 false Economic purchase... REGULATION CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Solicitation of Bids 14.212 Economic purchase quantities (supplies). Contracting officers shall comply with the economic purchase quantity...

  1. 48 CFR 14.212 - Economic purchase quantities (supplies).

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 1 2014-10-01 2014-10-01 false Economic purchase... REGULATION CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Solicitation of Bids 14.212 Economic purchase quantities (supplies). Contracting officers shall comply with the economic purchase quantity...

  2. 48 CFR 14.212 - Economic purchase quantities (supplies).

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 1 2011-10-01 2011-10-01 false Economic purchase... REGULATION CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Solicitation of Bids 14.212 Economic purchase quantities (supplies). Contracting officers shall comply with the economic purchase quantity...

  3. 48 CFR 14.203-1 - Transmittal to prospective bidders.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Solicitation of Bids 14.203-1 Transmittal to prospective... outside the United States shall be sent by electronic data interchange or air mail if security...

  4. 48 CFR 214.407-3 - Other mistakes disclosed before award.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...) Missile Defense Agency: General Counsel, MDA. (ix) Defense Contract Management Agency: General Counsel... before award. 214.407-3 Section 214.407-3 Federal Acquisition Regulations System DEFENSE ACQUISITION REGULATIONS SYSTEM, DEPARTMENT OF DEFENSE CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Opening of...

  5. 48 CFR 1314.409 - Information to bidders.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Information to bidders. 1314.409 Section 1314.409 Federal Acquisition Regulations System DEPARTMENT OF COMMERCE CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Opening of Bids and Awards of Contracts 1314.409 Information to...

  6. 48 CFR 414.409 - Information to bidders.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 4 2010-10-01 2010-10-01 false Information to bidders. 414.409 Section 414.409 Federal Acquisition Regulations System DEPARTMENT OF AGRICULTURE CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Opening of Bids and Award of Contract 414.409 Information to...

  7. 48 CFR 14.409 - Information to bidders.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Information to bidders. 14.409 Section 14.409 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Opening of Bids and Award of Contract 14.409 Information to...

  8. 48 CFR 14.202-5 - Descriptive literature.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 1 2014-10-01 2014-10-01 false Descriptive literature. 14... CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Solicitation of Bids 14.202-5 Descriptive literature. (a) Policy. Contracting officers must not require bidders to furnish descriptive literature unless it is...

  9. 48 CFR 14.202-5 - Descriptive literature.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 1 2013-10-01 2013-10-01 false Descriptive literature. 14... CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Solicitation of Bids 14.202-5 Descriptive literature. (a) Policy. Contracting officers must not require bidders to furnish descriptive literature unless it is...

  10. 48 CFR 14.202-5 - Descriptive literature.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 1 2012-10-01 2012-10-01 false Descriptive literature. 14... CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Solicitation of Bids 14.202-5 Descriptive literature. (a) Policy. Contracting officers must not require bidders to furnish descriptive literature unless it is...

  11. 48 CFR 14.202-5 - Descriptive literature.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 1 2011-10-01 2011-10-01 false Descriptive literature. 14... CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Solicitation of Bids 14.202-5 Descriptive literature. (a) Policy. Contracting officers must not require bidders to furnish descriptive literature unless it is...

  12. 48 CFR 14.202-5 - Descriptive literature.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Descriptive literature. 14... CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Solicitation of Bids 14.202-5 Descriptive literature. (a) Policy. Contracting officers must not require bidders to furnish descriptive literature unless it is...

  13. 48 CFR 214.407-3 - Other mistakes disclosed before award.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...) Missile Defense Agency: General Counsel, MDA. (ix) Defense Contract Management Agency: General Counsel... before award. 214.407-3 Section 214.407-3 Federal Acquisition Regulations System DEFENSE ACQUISITION REGULATIONS SYSTEM, DEPARTMENT OF DEFENSE CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Opening of...

  14. 48 CFR 214.407-3 - Other mistakes disclosed before award.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...) Missile Defense Agency: General Counsel, MDA. (ix) Defense Contract Management Agency: General Counsel... before award. 214.407-3 Section 214.407-3 Federal Acquisition Regulations System DEFENSE ACQUISITION REGULATIONS SYSTEM, DEPARTMENT OF DEFENSE CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Opening of...

  15. 48 CFR 214.407-3 - Other mistakes disclosed before award.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...) Missile Defense Agency: General Counsel, MDA. (ix) Defense Contract Management Agency: General Counsel... before award. 214.407-3 Section 214.407-3 Federal Acquisition Regulations System DEFENSE ACQUISITION REGULATIONS SYSTEM, DEPARTMENT OF DEFENSE CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Opening of...

  16. 48 CFR 214.407-3 - Other mistakes disclosed before award.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...) Missile Defense Agency: General Counsel, MDA. (ix) Defense Contract Management Agency: General Counsel... before award. 214.407-3 Section 214.407-3 Federal Acquisition Regulations System DEFENSE ACQUISITION REGULATIONS SYSTEM, DEPARTMENT OF DEFENSE CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Opening of...

  17. Contracting/expanding self-sealing cryogenic tube seals

    NASA Technical Reports Server (NTRS)

    Jia, Lin X. (Inventor)

    1997-01-01

    Contracting/expanding self-sealing cryogenic tube seals are disclosed which use the different properties of thermal contraction and expansion of selected dissimilar materials in accord with certain design criteria to yield self-tightening seals via sloped-surface sealing. The seals of the subject invention are reusable, simple to assemble, and adaptable to a wide variety of cryogenic applications.

  18. Contracting/expanding self-sealing cryogenic tube seals

    NASA Technical Reports Server (NTRS)

    Jia, Lin X. (Inventor)

    1997-01-01

    Contracting/expanding self-sealing cryogenic tube seals are disclosed which use the different properties of thermal contraction and expansion of selected dissimilar materials in accord with certain design criteria to yield self-tightening seals via sloped-surface sealing. The seals of the subject invention are reusable, simple to assemble, adaptable to a wide variety of cryogenic applications.

  19. 48 CFR 2014.407 - Mistakes in bids.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 6 2010-10-01 2010-10-01 true Mistakes in bids. 2014.407 Section 2014.407 Federal Acquisition Regulations System NUCLEAR REGULATORY COMMISSION CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Opening of Bids and Award of Contract 2014.407 Mistakes in bids. ...

  20. 48 CFR 3414.406 - Mistakes in bids.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 7 2010-10-01 2010-10-01 false Mistakes in bids. 3414.406 Section 3414.406 Federal Acquisition Regulations System DEPARTMENT OF EDUCATION ACQUISITION REGULATION CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Opening of Bids and Award of Contract 3414.406 Mistakes...

  1. 48 CFR 14.408-4 - Economic price adjustment.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Economic price adjustment... CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Opening of Bids and Award of Contract 14.408-4 Economic price adjustment. (a) Bidder proposes economic price adjustment. (1) When a solicitation does not...

  2. 48 CFR 14.408-4 - Economic price adjustment.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 1 2011-10-01 2011-10-01 false Economic price adjustment... CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Opening of Bids and Award of Contract 14.408-4 Economic price adjustment. (a) Bidder proposes economic price adjustment. (1) When a solicitation does not...

  3. 48 CFR 14.408-4 - Economic price adjustment.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 1 2013-10-01 2013-10-01 false Economic price adjustment... CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Opening of Bids and Award of Contract 14.408-4 Economic price adjustment. (a) Bidder proposes economic price adjustment. (1) When a solicitation does not...

  4. 48 CFR 14.408-4 - Economic price adjustment.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 1 2014-10-01 2014-10-01 false Economic price adjustment... CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Opening of Bids and Award of Contract 14.408-4 Economic price adjustment. (a) Bidder proposes economic price adjustment. (1) When a solicitation does not...

  5. 48 CFR 14.408-4 - Economic price adjustment.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 1 2012-10-01 2012-10-01 false Economic price adjustment... CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Opening of Bids and Award of Contract 14.408-4 Economic price adjustment. (a) Bidder proposes economic price adjustment. (1) When a solicitation does not...

  6. 48 CFR 714.406-4 - Disclosure of mistakes after award.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Disclosure of mistakes after award. 714.406-4 Section 714.406-4 Federal Acquisition Regulations System AGENCY FOR INTERNATIONAL DEVELOPMENT CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Opening of Bids and Award of Contract 714...

  7. 48 CFR 714.406-3 - Other mistakes disclosed before award.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Other mistakes disclosed before award. 714.406-3 Section 714.406-3 Federal Acquisition Regulations System AGENCY FOR INTERNATIONAL DEVELOPMENT CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Opening of Bids and Award of Contract 714...

  8. 48 CFR 714.406-3 - Other mistakes disclosed before award.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 5 2011-10-01 2011-10-01 false Other mistakes disclosed before award. 714.406-3 Section 714.406-3 Federal Acquisition Regulations System AGENCY FOR INTERNATIONAL DEVELOPMENT CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Opening of Bids and Award of Contract 714...

  9. 48 CFR 714.406-4 - Disclosure of mistakes after award.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 5 2011-10-01 2011-10-01 false Disclosure of mistakes after award. 714.406-4 Section 714.406-4 Federal Acquisition Regulations System AGENCY FOR INTERNATIONAL DEVELOPMENT CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Opening of Bids and Award of Contract 714...

  10. 48 CFR 1614.000 - Applicability.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 6 2014-10-01 2014-10-01 false Applicability. 1614.000 Section 1614.000 Federal Acquisition Regulations System OFFICE OF PERSONNEL MANAGEMENT FEDERAL EMPLOYEES HEALTH BENEFITS ACQUISITION REGULATION CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING 1614.000...

  11. 48 CFR 1614.000 - Applicability.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 6 2013-10-01 2013-10-01 false Applicability. 1614.000 Section 1614.000 Federal Acquisition Regulations System OFFICE OF PERSONNEL MANAGEMENT FEDERAL EMPLOYEES HEALTH BENEFITS ACQUISITION REGULATION CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING 1614.000...

  12. 48 CFR 1614.000 - Applicability.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 6 2010-10-01 2010-10-01 true Applicability. 1614.000 Section 1614.000 Federal Acquisition Regulations System OFFICE OF PERSONNEL MANAGEMENT FEDERAL EMPLOYEES HEALTH BENEFITS ACQUISITION REGULATION CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING 1614.000...

  13. 48 CFR 1614.000 - Applicability.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 6 2011-10-01 2011-10-01 false Applicability. 1614.000 Section 1614.000 Federal Acquisition Regulations System OFFICE OF PERSONNEL MANAGEMENT FEDERAL EMPLOYEES HEALTH BENEFITS ACQUISITION REGULATION CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING 1614.000...

  14. 48 CFR 1614.000 - Applicability.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 6 2012-10-01 2012-10-01 false Applicability. 1614.000 Section 1614.000 Federal Acquisition Regulations System OFFICE OF PERSONNEL MANAGEMENT FEDERAL EMPLOYEES HEALTH BENEFITS ACQUISITION REGULATION CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING 1614.000...

  15. 48 CFR 14.503-1 - Step one.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Step one. 14.503-1 Section... AND CONTRACT TYPES SEALED BIDDING Two-Step Sealed Bidding 14.503-1 Step one. (a) Requests for... use the two step method. (3) The requirements of the technical proposal. (4) The evaluation criteria...

  16. 48 CFR 2014.201-670 - Solicitation provisions.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 6 2010-10-01 2010-10-01 true Solicitation provisions. 2014.201-670 Section 2014.201-670 Federal Acquisition Regulations System NUCLEAR REGULATORY COMMISSION CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Solicitation of Bids 2014.201-670 Solicitation...

  17. 48 CFR 14.210 - Qualified products.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Qualified products. 14.210 Section 14.210 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Solicitation of Bids 14.210 Qualified products. See subpart 9.2. ...

  18. 48 CFR 42.1205 - Agreement to recognize contractor's change of name.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... each the contract number and type, and name and address of the contracting office. The contracting... executed this Agreement as of the day and year first above written. UNITED STATES OF AMERICA, By Title ABC... governing body and within the scope of its corporate powers. Witness my hand and the seal of this...

  19. 48 CFR 14.408-6 - Equal low bids.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Equal low bids. 14.408-6... AND CONTRACT TYPES SEALED BIDDING Opening of Bids and Award of Contract 14.408-6 Equal low bids. (a) Contracts shall be awarded in the following order of priority when two or more low bids are equal in all...

  20. 48 CFR 14.203 - Methods of soliciting bids.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 1 2014-10-01 2014-10-01 false Methods of soliciting bids. 14.203 Section 14.203 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Solicitation of Bids 14.203 Methods of soliciting bids. ...

  1. 48 CFR 14.203 - Methods of soliciting bids.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Methods of soliciting bids. 14.203 Section 14.203 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Solicitation of Bids 14.203 Methods of soliciting bids. ...

  2. 48 CFR 2014.201 - Preparation of invitation for bids.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 6 2010-10-01 2010-10-01 true Preparation of invitation for bids. 2014.201 Section 2014.201 Federal Acquisition Regulations System NUCLEAR REGULATORY COMMISSION CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Solicitation of Bids 2014.201 Preparation of...

  3. 48 CFR 514.202-5 - Descriptive literature.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 4 2011-10-01 2011-10-01 false Descriptive literature... CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Solicitation of Bids 514.202-5 Descriptive literature... FAR 52.211-6 satisfies the requirement for descriptive literature. [74 FR 47739, Sept. 17, 2009] ...

  4. 48 CFR 514.202-5 - Descriptive literature.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 4 2014-10-01 2014-10-01 false Descriptive literature... CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Solicitation of Bids 514.202-5 Descriptive literature... FAR 52.211-6 satisfies the requirement for descriptive literature. [74 FR 47739, Sept. 17, 2009] ...

  5. 48 CFR 514.202-5 - Descriptive literature.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 4 2013-10-01 2013-10-01 false Descriptive literature... CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Solicitation of Bids 514.202-5 Descriptive literature... FAR 52.211-6 satisfies the requirement for descriptive literature. [74 FR 47739, Sept. 17, 2009] ...

  6. 48 CFR 514.202-5 - Descriptive literature.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 4 2012-10-01 2012-10-01 false Descriptive literature... CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Solicitation of Bids 514.202-5 Descriptive literature... FAR 52.211-6 satisfies the requirement for descriptive literature. [74 FR 47739, Sept. 17, 2009] ...

  7. 48 CFR 514.202-5 - Descriptive literature.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 4 2010-10-01 2010-10-01 false Descriptive literature... CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Solicitation of Bids 514.202-5 Descriptive literature... FAR 52.211-6 satisfies the requirement for descriptive literature. [74 FR 47739, Sept. 17, 2009] ...

  8. 48 CFR 14.203-3 - Master solicitation.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 1 2012-10-01 2012-10-01 false Master solicitation. 14... CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Solicitation of Bids 14.203-3 Master solicitation. The master solicitation is provided to potential sources who are requested to retain it for continued and...

  9. 48 CFR 14.203-3 - Master solicitation.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 1 2011-10-01 2011-10-01 false Master solicitation. 14... CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Solicitation of Bids 14.203-3 Master solicitation. The master solicitation is provided to potential sources who are requested to retain it for continued and...

  10. 48 CFR 14.203-3 - Master solicitation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Master solicitation. 14... CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Solicitation of Bids 14.203-3 Master solicitation. The master solicitation is provided to potential sources who are requested to retain it for continued and...

  11. 48 CFR 14.203-3 - Master solicitation.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 1 2014-10-01 2014-10-01 false Master solicitation. 14... CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Solicitation of Bids 14.203-3 Master solicitation. The master solicitation is provided to potential sources who are requested to retain it for continued and...

  12. 48 CFR 14.203-3 - Master solicitation.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 1 2013-10-01 2013-10-01 false Master solicitation. 14... CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Solicitation of Bids 14.203-3 Master solicitation. The master solicitation is provided to potential sources who are requested to retain it for continued and...

  13. 48 CFR 514.270-2 - Guidelines for use.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 4 2010-10-01 2010-10-01 false Guidelines for use. 514.270-2 Section 514.270-2 Federal Acquisition Regulations System GENERAL SERVICES ADMINISTRATION CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Solicitation of Bids 514.270-2 Guidelines for use. (a...

  14. 48 CFR 814.304 - Submission, modification, and withdrawal of bids.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Submission, modification, and withdrawal of bids. 814.304 Section 814.304 Federal Acquisition Regulations System DEPARTMENT OF VETERANS AFFAIRS CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Submission of Bids 814.304...

  15. 48 CFR 3414.406-3 - Other mistakes disclosed before award.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 7 2010-10-01 2010-10-01 false Other mistakes disclosed before award. 3414.406-3 Section 3414.406-3 Federal Acquisition Regulations System DEPARTMENT OF EDUCATION ACQUISITION REGULATION CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Opening of Bids and...

  16. 48 CFR 614.201-70 - Use of English language.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 4 2010-10-01 2010-10-01 false Use of English language. 614.201-70 Section 614.201-70 Federal Acquisition Regulations System DEPARTMENT OF STATE CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Solicitation of Bids 614.201-70 Use of English language. Use of...

  17. 48 CFR 614.201-70 - Use of English language.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 4 2012-10-01 2012-10-01 false Use of English language. 614.201-70 Section 614.201-70 Federal Acquisition Regulations System DEPARTMENT OF STATE CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Solicitation of Bids 614.201-70 Use of English language. Use of...

  18. 48 CFR 614.201-70 - Use of English language.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 4 2014-10-01 2014-10-01 false Use of English language. 614.201-70 Section 614.201-70 Federal Acquisition Regulations System DEPARTMENT OF STATE CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Solicitation of Bids 614.201-70 Use of English language. Use of...

  19. 48 CFR 614.201-70 - Use of English language.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 4 2013-10-01 2013-10-01 false Use of English language. 614.201-70 Section 614.201-70 Federal Acquisition Regulations System DEPARTMENT OF STATE CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Solicitation of Bids 614.201-70 Use of English language. Use of...

  20. 48 CFR 614.201-70 - Use of English language.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 4 2011-10-01 2011-10-01 false Use of English language... METHODS AND CONTRACT TYPES SEALED BIDDING Solicitation of Bids 614.201-70 Use of English language. Use of English language solicitations and contracts is mandatory unless a deviation has been approved by the...

  1. 48 CFR 14.202-8 - Electronic bids.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 1 2013-10-01 2013-10-01 false Electronic bids. 14.202-8... AND CONTRACT TYPES SEALED BIDDING Solicitation of Bids 14.202-8 Electronic bids. In accordance with subpart 4.5, contracting officers may authorize use of electronic commerce for submission of bids. If...

  2. 48 CFR 14.202-8 - Electronic bids.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 1 2014-10-01 2014-10-01 false Electronic bids. 14.202-8... AND CONTRACT TYPES SEALED BIDDING Solicitation of Bids 14.202-8 Electronic bids. In accordance with subpart 4.5, contracting officers may authorize use of electronic commerce for submission of bids. If...

  3. 48 CFR 14.202-8 - Electronic bids.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 1 2011-10-01 2011-10-01 false Electronic bids. 14.202-8... AND CONTRACT TYPES SEALED BIDDING Solicitation of Bids 14.202-8 Electronic bids. In accordance with subpart 4.5, contracting officers may authorize use of electronic commerce for submission of bids. If...

  4. 48 CFR 14.202-8 - Electronic bids.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 1 2012-10-01 2012-10-01 false Electronic bids. 14.202-8... AND CONTRACT TYPES SEALED BIDDING Solicitation of Bids 14.202-8 Electronic bids. In accordance with subpart 4.5, contracting officers may authorize use of electronic commerce for submission of bids. If...

  5. 48 CFR 14.202-8 - Electronic bids.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Electronic bids. 14.202-8... AND CONTRACT TYPES SEALED BIDDING Solicitation of Bids 14.202-8 Electronic bids. In accordance with subpart 4.5, contracting officers may authorize use of electronic commerce for submission of bids. If...

  6. 48 CFR 32.405 - Applying Pub. L. 85-804 to advance payments under sealed bid contracts.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... advance payments under sealed bid contracts. 32.405 Section 32.405 Federal Acquisition Regulations System... Non-Commercial Items 32.405 Applying Pub. L. 85-804 to advance payments under sealed bid contracts. (a... provisions of law relating to contracts, as explained in 50.101-1(a), also include making advance payments...

  7. 48 CFR 6101.34 - Seal of the Board [Rule 34].

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 7 2010-10-01 2010-10-01 false Seal of the Board [Rule 34..., GENERAL SERVICES ADMINISTRATION CONTRACT DISPUTE CASES 6101.34 Seal of the Board [Rule 34]. The Seal of... Contract Appeals.” The Seal shall be the means of authentication of all records, notices, orders...

  8. 48 CFR 6101.34 - Seal of the Board [Rule 34].

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 7 2011-10-01 2011-10-01 false Seal of the Board [Rule 34..., GENERAL SERVICES ADMINISTRATION CONTRACT DISPUTE CASES 6101.34 Seal of the Board [Rule 34]. The Seal of... Contract Appeals.” The Seal shall be the means of authentication of all records, notices, orders...

  9. Analog Video Authentication and Seal Verification Equipment Development

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

    Gregory Lancaster

    Under contract to the US Department of Energy in support of arms control treaty verification activities, the Savannah River National Laboratory in conjunction with the Pacific Northwest National Laboratory, the Idaho National Laboratory and Milagro Consulting, LLC developed equipment for use within a chain of custody regime. This paper discussed two specific devices, the Authentication Through the Lens (ATL) analog video authentication system and a photographic multi-seal reader. Both of these devices have been demonstrated in a field trial, and the experience gained throughout will also be discussed. Typically, cryptographic methods are used to prove the authenticity of digital imagesmore » and video used in arms control chain of custody applications. However, in some applications analog cameras are used. Since cryptographic authentication methods will not work on analog video streams, a simple method of authenticating analog video was developed and tested. A photographic multi-seal reader was developed to image different types of visual unique identifiers for use in chain of custody and authentication activities. This seal reader is unique in its ability to image various types of seals including the Cobra Seal, Reflective Particle Tags, and adhesive seals. Flicker comparison is used to compare before and after images collected with the seal reader in order to detect tampering and verify the integrity of the seal.« less

  10. Seal Technology for Liquid Oxygen (LOX) Turbopumps

    NASA Technical Reports Server (NTRS)

    Shapiro, Wilbur; Hamm, Robert

    1985-01-01

    Two types of advanced seals for liquid oxygen (LOX) turbopumps were investigated. One was a spiral-groove face seal whose function is to seal high-pressure LOX at the impeller end of the turbopump. The other was a floating-ring, Rayleigh-step, helium buffered seal used to prevent LOX ingress to the turbine side of the unit. For each seal type, two sizes were investigated (50 and 20 mm). A turbine-driven test rig was designed and manufactured, and a test program was completed on the 50 mm floating-ring, Rayleigh-step, helium buffered seal. Significant results were: vaporization in the flow path could cause failure by overheating; therefore, the spiral-groove pumping portion of the seal that provides the fluid film must circulate fluid without disruption if vaporization occurs in the sealing dam. This is successfully accomplished by a pressure-balanced spiral-groove concept that is described. The spiral-groove configuration is affected by turbulence in the fluid film and pressure drops due to fluid inertia at sudden contractions. The net results of these effects are deep grooves, large operating films, and high power loss when compared against seals operating with laminar films. Turbulence and inertia are induced by the high-density and low-viscosity characteristics of LOX. The program clearly pointed out the need to consider system environmental factors such as thermal and centrifugal distortions and rotor vibrations in the seal design.

  11. Measurement and evaluation of swirl-type flow in labyrinth seals of conventional turbine stages

    NASA Technical Reports Server (NTRS)

    Hauck, L.

    1982-01-01

    The effects of load factor and rotor eccentricity were determined on flow conditions in test series for two stages. The results indicate that swirl-type entry flow follows the rules of potential swirl. Within the labyrinth cavities two spatial separated flow areas are considered. A dominating flow in periphera direction nearly fills the space between the sealing strips and the ceiling of the cavity. Below this flow, an area of axial mass transport is situated, with a slight peripheral component, limited on the nearest surroundings of the seals gap and the rotor surface. Between both flows, an exchange of energy takes place. Within the gaps, flow direction depends on axial velocity and therefore on variable flow contraction. A balance of energy within the seal and the cavities interprets the results of lateral force measurements as an influence of friction at the sealing strips surface and the rotating shaft surface. Stages with their blades put together in buckets by means of shrouding segments are particularly influenced by the rotating speed of the shrouding.

  12. Leaf seal for inner and outer casings of a turbine

    DOEpatents

    Schroder, Mark Stewart; Leach, David

    2002-01-01

    A plurality of arcuate, circumferentially extending leaf seal segments form an annular seal spanning between annular sealing surfaces of inner and outer casings of a turbine. The ends of the adjoining seal segments have circumferential gaps to enable circumferential expansion and contraction of the segments. The end of a first segment includes a tab projecting into a recess of a second end of a second segment. Edges of the tab seal against the sealing surfaces of the inner and outer casings have a narrow clearance with opposed edges of the recess. An overlying cover plate spans the joint. Leakage flow is maintained at a minimum because of the reduced gap between the radially spaced edges of the tab and recess, while the seal segments retain the capacity to expand and contract circumferentially.

  13. 19 CFR 115.2 - Application.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... is used for the first time for transport under Customs seal. The TIR Convention, 1975, generally... that country is a contracting party to the Convention, may approve a series of road vehicles or containers presented for design type approval. The procedures for applying for certification are contained in...

  14. 19 CFR 115.2 - Application.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... is used for the first time for transport under Customs seal. The TIR Convention, 1975, generally... that country is a contracting party to the Convention, may approve a series of road vehicles or containers presented for design type approval. The procedures for applying for certification are contained in...

  15. 19 CFR 115.2 - Application.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... is used for the first time for transport under Customs seal. The TIR Convention, 1975, generally... that country is a contracting party to the Convention, may approve a series of road vehicles or containers presented for design type approval. The procedures for applying for certification are contained in...

  16. 19 CFR 115.2 - Application.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... is used for the first time for transport under Customs seal. The TIR Convention, 1975, generally... that country is a contracting party to the Convention, may approve a series of road vehicles or containers presented for design type approval. The procedures for applying for certification are contained in...

  17. Seal Apparatus and Methods to Manufacture Thereof

    NASA Technical Reports Server (NTRS)

    Richard, James A. (Inventor)

    2013-01-01

    In some implementations, apparatus and methods are provided through which a dynamic cryogenic seal is manufactured. In some implementations, the seal includes a retainer and a spring-seal assembly, the assembly being comprised of a main spring housing and fluorine-containing polymer seals. In some implementations, either a radial seal, or an axial (or "piston seal") is provided. In some implementations, methods of manufacturing the dynamic cryogenic seal are also provided. In some implementations, the methods include assembling the components while either heated or cooled, taking advantage of thermal expansion and contraction, such that there is a strong interference fit between the components at room temperature. In some implementations, this process ensures that the weaker fluorine-containing polymer seal is forced to expand and contract with the stronger retainer and spring and is under constant preload. In some implementations, the fluorine-containing polymer is therefore fluidized and retained, and can not lift off.

  18. The 1992 Seals Flow Code Development Workshop

    NASA Technical Reports Server (NTRS)

    Liang, Anita D.; Hendricks, Robert C.

    1993-01-01

    A two-day meeting was conducted at the NASA Lewis Research Center on August 5 and 6, 1992, to inform the technical community of the progress of NASA Contract NAS3-26544. This contract was established in 1990 to develop industrial and CFD codes for the design and analysis of seals. Codes were demonstrated and disseminated to the user community for evaluation. The peer review panel which was formed in 1991 provided recommendations on this effort. The technical community presented results of their activities in the area of seals, with particular emphasis on brush seal systems.

  19. 48 CFR 14.202-1 - Bidding time.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Bidding time. 14.202-1... AND CONTRACT TYPES SEALED BIDDING Solicitation of Bids 14.202-1 Bidding time. (a) Policy. A reasonable time for prospective bidders to prepare and submit bids shall be allowed in all invitations, consistent...

  20. 48 CFR 14.202-1 - Bidding time.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 1 2012-10-01 2012-10-01 false Bidding time. 14.202-1... AND CONTRACT TYPES SEALED BIDDING Solicitation of Bids 14.202-1 Bidding time. (a) Policy. A reasonable time for prospective bidders to prepare and submit bids shall be allowed in all invitations, consistent...

  1. 48 CFR 14.202-1 - Bidding time.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 1 2011-10-01 2011-10-01 false Bidding time. 14.202-1... AND CONTRACT TYPES SEALED BIDDING Solicitation of Bids 14.202-1 Bidding time. (a) Policy. A reasonable time for prospective bidders to prepare and submit bids shall be allowed in all invitations, consistent...

  2. 48 CFR 14.202-1 - Bidding time.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 1 2014-10-01 2014-10-01 false Bidding time. 14.202-1... AND CONTRACT TYPES SEALED BIDDING Solicitation of Bids 14.202-1 Bidding time. (a) Policy. A reasonable time for prospective bidders to prepare and submit bids shall be allowed in all invitations, consistent...

  3. 48 CFR 14.202-1 - Bidding time.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 1 2013-10-01 2013-10-01 false Bidding time. 14.202-1... AND CONTRACT TYPES SEALED BIDDING Solicitation of Bids 14.202-1 Bidding time. (a) Policy. A reasonable time for prospective bidders to prepare and submit bids shall be allowed in all invitations, consistent...

  4. 78 FR 70600 - International Mail Contract

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-26

    ... States Postal Service of Type 2 Rate Adjustment, and Notice of Filing Functionally Equivalent Agreement... requirements. In addition to the Notice, the Postal Service filed an application for non-public treatment of... documentation under seal. Id. On November 18, 2013, the Postal Service filed with the Commission the non-public...

  5. 41 CFR 128-1.5007 - Reproduction of departmental and bureau seals.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... departmental and bureau seals. 128-1.5007 Section 128-1.5007 Public Contracts and Property Management Federal... bureau seals. (a) Requests for permission to reproduce the Departmental seal for commercial, educational... seals of the Federal Bureau of Investigation, the Bureau of Prisons, the Federal Prison Industries, the...

  6. 41 CFR 128-1.5007 - Reproduction of departmental and bureau seals.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... departmental and bureau seals. 128-1.5007 Section 128-1.5007 Public Contracts and Property Management Federal... bureau seals. (a) Requests for permission to reproduce the Departmental seal for commercial, educational... seals of the Federal Bureau of Investigation, the Bureau of Prisons, the Federal Prison Industries, the...

  7. 41 CFR 102-38.85 - What is a sealed bid sale?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 41 Public Contracts and Property Management 3 2011-01-01 2011-01-01 false What is a sealed bid sale? 102-38.85 Section 102-38.85 Public Contracts and Property Management Federal Property Management Regulations System (Continued) FEDERAL MANAGEMENT REGULATION PERSONAL PROPERTY 38-SALE OF PERSONAL PROPERTY...

  8. 41 CFR 102-38.85 - What is a sealed bid sale?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false What is a sealed bid sale? 102-38.85 Section 102-38.85 Public Contracts and Property Management Federal Property Management Regulations System (Continued) FEDERAL MANAGEMENT REGULATION PERSONAL PROPERTY 38-SALE OF PERSONAL PROPERTY...

  9. 41 CFR 102-38.85 - What is a sealed bid sale?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 41 Public Contracts and Property Management 3 2013-07-01 2013-07-01 false What is a sealed bid sale? 102-38.85 Section 102-38.85 Public Contracts and Property Management Federal Property Management Regulations System (Continued) FEDERAL MANAGEMENT REGULATION PERSONAL PROPERTY 38-SALE OF PERSONAL PROPERTY...

  10. 41 CFR 102-38.85 - What is a sealed bid sale?

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 41 Public Contracts and Property Management 3 2012-01-01 2012-01-01 false What is a sealed bid sale? 102-38.85 Section 102-38.85 Public Contracts and Property Management Federal Property Management Regulations System (Continued) FEDERAL MANAGEMENT REGULATION PERSONAL PROPERTY 38-SALE OF PERSONAL PROPERTY...

  11. 41 CFR 102-38.85 - What is a sealed bid sale?

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 41 Public Contracts and Property Management 3 2014-01-01 2014-01-01 false What is a sealed bid sale? 102-38.85 Section 102-38.85 Public Contracts and Property Management Federal Property Management Regulations System (Continued) FEDERAL MANAGEMENT REGULATION PERSONAL PROPERTY 38-SALE OF PERSONAL PROPERTY...

  12. 78 FR 4478 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-22

    ... Equivalent Global Plus 2C Contract Negotiated Service Agreement and Application for Non-Public Treatment of... Equivalent Global Plus 2C Agreements, January 13, 2012. Customers for Global Plus 2C contracts are Postal... application for non-public treatment of material filed under seal. The material filed under seal consists of...

  13. Develop Efficient Leak Proof M1 Abrams Plenum Seal

    DTIC Science & Technology

    2014-05-07

    burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching...ADDRESS. 1 . REPORT DATE (DD-MM-YYYY) 2. REPORT TYPE 3. DATES COVERED (From - To) 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c... 1 Background ................................................................................................................. 6 1.1 Problem

  14. Improved cryogenic shaft seals

    NASA Technical Reports Server (NTRS)

    Gillon, W. A., Jr.; Tellier, G. F.

    1976-01-01

    Seals are designed for use with liquid propellant ball valves at temperatures ranging from -400 F to 130 F and 8,000 psig. Seals are capable of sustaining 90 degree rotation, with substantial amount of lateral and axial play, caused by large pressure loads and differential thermal contraction.

  15. 48 CFR 225.870-3 - Submission of offers.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... sealed bids in terms of U.S. currency. Do not adjust contracts awarded under sealed bidding for losses or gains from fluctuation in exchange rates. (d) Except for sealed bids, the Canadian Commercial Corporation normally will submit offers and quotations in terms of Canadian currency. The Corporation may, at...

  16. 48 CFR 52.214-28 - Subcontractor Certified Cost or Pricing Data-Modifications-Sealed Bidding.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Cost or Pricing Data-Modifications-Sealed Bidding. 52.214-28 Section 52.214-28 Federal Acquisition... CONTRACT CLAUSES Text of Provisions and Clauses 52.214-28 Subcontractor Certified Cost or Pricing Data... Cost or Pricing Data—Modifications—Sealed Bidding (OCT 2010) (a) The requirements of paragraphs (b) and...

  17. Signed, Sealed and Delivered.

    ERIC Educational Resources Information Center

    Jackson, Lisa M.

    1997-01-01

    Describes one Massachusetts school district's solution to rising energy costs by using contract services to head off capital costs and guarantee savings. Highlights keys to successful management of this contracting system and the elements that make up a successful contract services candidate. (GR)

  18. O-Ring sealing arrangements for ultra-high vacuum systems

    DOEpatents

    Kim, Chang-Kyo; Flaherty, Robert

    1981-01-01

    An all metal reusable O-ring sealing arrangement for sealing two concentric tubes in an ultra-high vacuum system. An O-ring of a heat recoverable alloy such as Nitinol is concentrically positioned between protruding sealing rings of the concentric tubes. The O-ring is installed between the tubes while in a stressed martensitic state and is made to undergo a thermally induced transformation to an austenitic state. During the transformation the O-ring expands outwardly and contracts inwardly toward a previously sized austenitic configuration, thereby sealing against the protruding sealing rings of the concentric tubes.

  19. 77 FR 143 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-03

    ... information under seal. In the Statement of Supporting Justification, Dennis R. Nicoski, Manager, Field Sales Strategy and Contracts, asserts that the contract will cover its attributable costs, make a positive...

  20. Design guide for helicopter transmission seals

    NASA Technical Reports Server (NTRS)

    Hayden, T. S.; Keller, C. H., Jr.

    1974-01-01

    A detailed approach for the selection and design of seals for helicopter transmissions is presented. There are two major types of seals presently being used and they are lip type seals and mechanical type seals. Lip type seals can be divided in conventional lip seals and hydrodynamic lip seals. Conventional lip seals can be used for slow-speed, low-pressure, low-temperature sealing. Hydrodynamic lip seals although they are as pressure and temperature limited as conventional lip seals, can operate at a higher speed. Mechanical types seals are comprised of face seals and circumferential seals. Face seals are capable of high speed, high pressure, and high temperature. Circumferential seals can be used in high-speed and high-temperature applications, but will leak excessively at moderate pressures. The performance goals of transmission seals are a life that is at least equal to the scheduled overhaul interval of the gearbox component and a leakage rate of near zero.

  1. 48 CFR 18.121 - Advance payments.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Law 85-804 (see Subpart 50.1, Extraordinary Contractual Actions). These advance payments may be made at or after award of sealed bid contracts, as well as negotiated contracts. (See 32.405.) [71 FR...

  2. 36 CFR 223.231 - Bidding methods.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 36 Parks, Forests, and Public Property 2 2010-07-01 2010-07-01 false Bidding methods. 223.231... methods. The Contracting Officer or designated forest officer shall offer advertised sales of special forest products through sealed bid or sealed bid followed by oral auction. The method selected shall: (a...

  3. 77 FR 1957 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-12

    ... Notice of Filing Two Functionally Equivalent Global Plus 2C Contracts Negotiated Service Agreements and Application for Non-Public Treatment of Materials Filed Under Seal, December 30, 2011 (Notice). See also... documents, under seal. Attachment 1 to the Notice is an application for non-public treatment of this...

  4. 77 FR 2098 - New Postal Product

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-13

    ... Competitive Products List and Notice of Filing Two Functionally Equivalent Global Plus 1C Contracts Negotiated Service Agreements and Application for Non-Public Treatment of Materials Filed Under Seal, December 30... under seal. Attachment 1 to the Notice is an application for non-public treatment of that material...

  5. Low thermal expansion seal ring support

    DOEpatents

    Dewis, David W.; Glezer, Boris

    2000-01-01

    Today, the trend is to increase the temperature of operation of gas turbine engines. To cool the components with compressor discharge air, robs air which could otherwise be used for combustion and creates a less efficient gas turbine engine. The present low thermal expansion sealing ring support system reduces the quantity of cooling air required while maintaining life and longevity of the components. Additionally, the low thermal expansion sealing ring reduces the clearance "C","C'" demanded between the interface between the sealing surface and the tip of the plurality of turbine blades. The sealing ring is supported by a plurality of support members in a manner in which the sealing ring and the plurality of support members independently expand and contract relative to each other and to other gas turbine engine components.

  6. 48 CFR 52.214-27 - Price Reduction for Defective Certified Cost or Pricing Data-Modifications-Sealed Bidding.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 2 2011-10-01 2011-10-01 false Price Reduction for... PROVISIONS AND CONTRACT CLAUSES Text of Provisions and Clauses 52.214-27 Price Reduction for Defective... following clause: Price Reduction for Defective Certified Cost or Pricing Data—Modifications—Sealed Bidding...

  7. 48 CFR 16.203-2 - Application.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... contract with economic price adjustment may be used when (i) there is serious doubt concerning the stability of market or labor conditions that will exist during an extended period of contract performance... limited to contingencies beyond the contractor's control. For use of economic price adjustment in sealed...

  8. Lifetime prediction of materials exposed to the natural space environment

    NASA Technical Reports Server (NTRS)

    Zee, Ralph

    1993-01-01

    The goal of this study is to model the lifetime of different types of seal materials based on results obtained from accelerated experiments. A semi-mechanistic approach was taken. Thermal aging data were taken from the literature whereas experiments were conducted at Auburn under this contract for selected environments. The seal materials of interest are Silicone 383, Silicone 650, Viton 835, and Viton 747. The relevant conditions include thermal, oxygen, inert gas, vacuum, and gamma radiation. Compression set data available from NASA were used to examine the thermal effect. Experiments were conducted at Auburn University and at NASA to isolate the role of thermal, oxygen, inert gas, vacuum, gamma irradiation, and proton irradiation. A simple discrete stress relaxation method was developed to determine the relaxation response of the elastomers. Dynamic mechanical thermal analysis was also used to characterize the mechanical response of the specimens. These provide a more meaningful correlation between mechanisms and degradation.

  9. 48 CFR 16.203-2 - Application.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... contract with economic price adjustment may be used when (i) there is serious doubt concerning the... limited to contingencies beyond the contractor's control. For use of economic price adjustment in sealed bid contracts, see 14.408-4. (a) In establishing the base level from which adjustment will be made...

  10. 48 CFR 22.404-8 - Notification of improper wage determination before award.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... FEDERAL ACQUISITION REGULATION SOCIOECONOMIC PROGRAMS APPLICATION OF LABOR LAWS TO GOVERNMENT ACQUISITIONS... determination is withdrawn by the Administrative Review Board. (b) In sealed bidding, the contracting officer... determination for the primary site of the work reaches the contracting officer before bid opening, the...

  11. Performance of the coned-face end seal with regard to energy conservation

    NASA Technical Reports Server (NTRS)

    Sehnal, J.; Sedy, J.; Zobens, A.; Etsion, I.

    1982-01-01

    The effects of face coning on seal performance are evaluated with particular regard to the energy saving potential of convex conedface end seals as indicated by torque reduction. Experiments were conducted using a conventional carbon flat-face pusher-type seal, a coned-face pusher-type seal, coned-face bellows-type seal, and a modified coned-face pusher-type seal intended for dynamically unstable operation, with shaft rotation at up to 8000 rpm, pressures of up to 2758 kPa, and a petroleum-based turbine oil as lubricant. Torque at the seal interface is found to be reduced by 42% when the standard flat-face seal is replaced by a coned seal, although the leakage of the cone-face seal was 11 times greater. Reduction of seal balance from 76.1 to 51.3% resulted in an additional 44% reduction in torque, although at the expense of excessive leakage, but did not produce unstable operation. Face temperatures were reduced by 33-56 C and wear was also reduced greatly on the cone face seals. Seal performance is noted to be in agreement with analytical calculations.

  12. 7 CFR 1753.8 - Contract construction procedures.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... of all bids including “Buy American” evaluations, if any, and all other evaluations required by law... Contract construction procedures. (a) Sealed, competitive bidding—(1) Bid opening date. The borrower is responsible for scheduling the bid opening date. If RUS review of P&S is required by § 1753.7, the borrower...

  13. Aeropropulsion Technology (APT). Task 23 - Stator Seal Cavity Flow Investigation

    NASA Technical Reports Server (NTRS)

    Heidegger, N. J.; Hall, E. J.; Delaney, R. A.

    1996-01-01

    The focus of NASA Contract NAS3-25950 Task 23 was to numerically investigate the flow through an axial compressor inner-banded stator seal cavity. The Allison/NASA developed ADPAC code was used to obtain all flow predictions. Flow through a labyrinth stator seal cavity of a high-speed compressor was modeled by coupling the cavity flow path and the main flow path of the compressor. A grid resolution study was performed to guarantee adequate grid spacing was used. Both unsteady rotor-stator-rotor interactions and steady-state isolated blade calculations were performed with and without the seal cavity present. A parameterized seal cavity study of the high-speed stator seal cavity collected a series of solutions for geometric variations. The parameter list included seal tooth gap, cavity depth, wheel speed, radial mismatch of hub flowpath, axial trench gap, hub corner treatments, and land edge treatments. Solution data presented includes radial and pitchwise distributions of flow variables and particle traces describing the flow character.

  14. Fuel cell cassette with compliant seal

    DOEpatents

    Karl, Haltiner, Jr. J.; Anthony, Derose J.; Klotzbach, Darasack C.; Schneider, Jonathan R.

    2017-11-07

    A fuel cell cassette for forming a fuel cell stack along a fuel cell axis includes a cell retainer, a plate positioned axially to the cell retainer and defining a space axially with the cell retainer, and a fuel cell having an anode layer and a cathode layer separated by an electrolyte layer. The outer perimeter of the fuel cell is positioned in the space between the plate and the cell retainer, thereby retaining the fuel cell and defining a cavity between the cell retainer, the fuel cell, and the plate. The fuel cell cassette also includes a seal disposed within the cavity for sealing the edge of the fuel cell. The seal is compliant at operational temperatures of the fuel cell, thereby allowing lateral expansion and contraction of the fuel cell within the cavity while maintaining sealing at the edge of the fuel cell.

  15. Electrically insulating and sealing frame

    DOEpatents

    Guthrie, Robin J.

    1983-11-08

    A combination gas seal and electrical insulator having a closed frame shape interconnects a fuel cell stack and a reactant gas plenum of a fuel cell generator. The frame can be of rectangular shape including at least one slidable spline connection in each side to permit expansion or contraction consistent with that of the walls of the gas plenum and fuel cell stack. The slidable spline connections in the frame sides minimizes lateral movement between the frame side members and sealing material interposed between the frame and the fuel cell stack or between the frame and the reactant gas plenum.

  16. Feasibility study of negative lift circumferential type seal for helicopter transmissions

    NASA Technical Reports Server (NTRS)

    Goldring, E. N.

    1977-01-01

    A new seal concept, the negative lift circumferential type seal, was evaluated under simulated helicopter transmission conditions. The bore of the circumferential seal contains step type geometry which produces a negative lift that urges the sealing segments towards the shaft surface. The seal size was a 2.5 inch bore and the test speeds were 7000 and 14,250 rpm. During the 300 hour test at typical transmission seal pressure (to 2 psig) the leakage was within acceptable limits and generally less than 0.1 cc/hour during the last 150 hours of testing. The wear to the carbon segments during the 300 hours was negligible.

  17. The Effects of Creatine Supplementation on Short-Term Exercise Performance of U.S. Navy Seals

    DTIC Science & Technology

    1999-12-01

    among the heart, central nervous system, and testes (46). During intense muscle contraction , PCr has been shown to rapidly decline. The decline in...muscular levels of PCr have been associated with muscle contraction and fatigue, an elevated PCr level prior to exercise could be postulated to... muscle contraction . Ex. Sports Sei. Rev. 26: 1-30, 1998. 21. Greenhaff, P. L., K. Bodin, K. Soderlund, and E. Hultman. Effect of oral creatine

  18. Sample Containerization and Sealing Techniques for Contamination Prevention and Preservation of Science Value for Mars Sample Return

    NASA Astrophysics Data System (ADS)

    Younse, Paulo

    Four sealing methods for encapsulating samples in 1 cm diameter thin-walled sample tubes were designed, along with a set of tests for characterization and evaluation of contamination prevention and sample preservation capability for the proposed Mars Sample Return (MSR) campaign. The sealing methods include a finned shape memory alloy (SMA) plug, expanding torque plug, contracting SMA ring cap, and expanding SMA ring plug. Mechanical strength and hermeticity of the seal were measured using a helium leak detector. Robustness of the seal to Mars simulant dust, surface abrasion, and pressure differentials were tested. Survivability tests were run to simulate thermal cycles on Mars, vibration from a Mars Ascent Vehicle (MAV), and shock from Earth Entry Vehicle (EEV) landing. Material compatibility with potential sample minerals and organic molecules were studied to select proper tube and seal materials that would not lead to adverse reactions nor contaminate the sample. Cleaning and sterilization techniques were executed on coupons made from the seal materials to assess compliance with planetary protection and contamination control. Finally, a method to cut a sealed tube for sample removal was designed and tested.

  19. Socio-metrics: Identifying Invisible Deviant Adversaries

    DTIC Science & Technology

    2015-12-07

    ELEMENT NUMBER 5b. GRANT NUMBER 5a. CONTRACT NUMBER Form Approved OMB NO. 0704-0188 3 . DATES COVERED (From - To) - UU UU UU UU 07-12-2015 1-Oct-2013 30...collaborate each other in conducting cyber-attacks at an unprecedented scale [ 3 ]. Monitoring OSNs and Internet forums is thus imperative to understand and...Socia/SEAL and in Section 3 , we present the results of using Socia/SEAL on data collected from real-world OSNs. Section 4 concludes this report

  20. Evaluation of new plastic compression (Ziegler) type of seals for long life planetary batteries

    NASA Technical Reports Server (NTRS)

    Frank, H. A.

    1973-01-01

    A program was initiated to develop improved types of terminal seals for aerospace Ni-Cd batteries. The approach used has not involved attempts, such as employed elsewhere, to improve the ceramic-to-metal seal that is now extensively employed for this application. Rather the approach has been directed toward the development and evaluation of new types of seals. Of prime interest in this initial investigation has been the Ziegler type of compression seal and in particular the injection molded version developed by the Bell Telephone Laboratories (BTL). A number of these units were designed, fabricated, and evaluated on an accelerated life test under a simulated battery environment. Results have shown that there are no major problems involved in scaling up the BTL small-size (5-amp) seal to a larger size (up to 50-amp) seal suitable for most JPL flight batteries. Five out of five such seals successfully completed over 10 months of continuous thermal cycling without developing any leaks greater than 1.8 x to 10 to the minus 9th power atm-cc-He/s.

  1. 75 FR 13415 - Federal Acquisition Regulation; FAR Case 2008-040, Use of Standard Form 26 - Award/Contract

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-19

    ... at FAR 53.215-1(a) to read ``Block 18 may not be used for negotiated procurements.'' This change does... U.S.C. chapter 35, et seq. List of Subjects in 48 CFR Parts 15 and 53 Government procurement. [[Page... negotiated procurement and emphasize that block 18 should only be checked when awarding a sealed bid contract...

  2. Fine-Scale Variability in Harbor Seal Foraging Behavior

    PubMed Central

    Wilson, Kenady; Lance, Monique; Jeffries, Steven; Acevedo-Gutiérrez, Alejandro

    2014-01-01

    Understanding the variability of foraging behavior within a population of predators is important for determining their role in the ecosystem and how they may respond to future ecosystem changes. However, such variability has seldom been studied in harbor seals on a fine spatial scale (<30 km). We used a combination of standard and Bayesian generalized linear mixed models to explore how environmental variables influenced the dive behavior of harbor seals. Time-depth recorders were deployed on harbor seals from two haul-out sites in the Salish Sea in 2007 (n = 18) and 2008 (n = 11). Three behavioral bout types were classified from six dive types within each bout; however, one of these bout types was related to haul-out activity and was excluded from analyses. Deep foraging bouts (Type I) were the predominant type used throughout the study; however, variation in the use of bout types was observed relative to haul-out site, season, sex, and light (day/night). The proportional use of Type I and Type II (shallow foraging/traveling) bouts differed dramatically between haul-out sites, seasons, sexes, and whether it was day or night; individual variability between seals also contributed to the observed differences. We hypothesize that this variation in dive behavior was related to habitat or prey specialization by seals from different haul-out sites, or individual variability between seals in the study area. The results highlight the potential influence of habitat and specialization on the foraging behavior of harbor seals, and may help explain the variability in diet that is observed between different haul-out site groups in this population. PMID:24717815

  3. SealSim Version 1.1

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

    SealSim 1.1 is a state-of-the-art, Microsoft Windows based computer program developed for the U.S. Department of Energy by Aspen Research Corporation with Contracted support from TNO TPD. It is intended to be used by manufacturers, engineers, educators, students, architects, and others to help determine the relative durability of Insulating Glass Units (IGU). As a function of time, SealSim 1.1 simulates the behaviour of an Insulating Glass Unit, exposed to realistic or user-defined weather climates. Stresses and strains in the IGU are calculated as a function of time, together with temperature distributions, gas permeation effects (gas loss, desiccant loading), dew pointmore » temperature, U-factor, etc. The current version of SealSim 1.1 supports double-glazing Units. where the spacer system is either a Thermo Plastic Spacer (TPS) or Box type spacer. For the determination of solar properties of glazing systems, SealSim 1.1 uses the Tntemational Glazing Database of LBNL, which is also used by OPTICS and WINDOW. The goal of the SealSim 1.1 simulations is to predict the IGU's average lifetime, expressed in terms of the "Durability Index", together with the associated failure mechanisms. The Durability Index of a particular IGU and its most probable failure mechanism can be compared with other IGU's. How the predicted Durability Index relates to the actual durability of an IGU is not known, simply because sufficient experimental data is lacking for describing the behaviour of IG Units over extended periods of time together with a lack of knowledge of the conditions it is subjected to and initial state of the CU at the time of manufacturing. In order to simulate the IGU behaviour in time, the conditions of the IGU must be defined; together with the weather and or climate that the IGU is subjected to. Using physical models of the IGU, SealSim 1.1 calculates tte response of the CU in time. These physical models are described in more detail in separate documents provided with the SealSim 1.1 program. Though much care was taken to test the correct implementation of physical sub models in SealSim 1.1, make the graphical user interface intuitive, making it robust, and to check all options that are available in SealSim 1.1, it will certainly suffer from the deficiencies of a first release. Aspen Research Corporation 1700 Buerkle Road St Paul, Minnesota 55110« less

  4. Mid-Term Progress Report on the Development of Army Closed Cycle Circulator (CCC) System.

    DTIC Science & Technology

    1979-09-20

    installation of the rotor assembly. The compressor shaft is sealed with a Crane Type 28 Kinetic Wedge gas seal for positive static sealing. A unitized...Pressure ratio 1.91 Horsepower 134 R (Molecular weight 18.67) 82.76 The compressor is fitted with a Crane Packing Company Type 28 gas seal. This seal...simply reading a digital voltmeter which is hooked up to the anemometer. The only preparation that the anemometer requires is that the operating

  5. 76 FR 21743 - General Services Administration Acquisition Regulation; Information Collection; Sealed Bidding

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-18

    ... comments on or before: June 17, 2011. FOR FURTHER INFORMATION CONTACT: Michael O. Jackson, Procurement Analyst, Contract Policy Branch, at telephone (202) 208-4949 or michaelo.jackson@gsa.gov . ADDRESSES...

  6. COMPARTMENTED REACTOR FUEL ELEMENT

    DOEpatents

    Cain, F.M. Jr.

    1962-09-11

    A method of making a nuclear reactor fuel element of the elongated red type is given wherein the fissionable fuel material is enclosed within a tubular metal cladding. The method comprises coating the metal cladding tube on its inside wall with a brazing alloy, inserting groups of cylindrical pellets of fissionable fuel material into the tube with spacing members between adjacent groups of pellets, sealing the ends of the tubes to leave a void space therewithin, heating the tube and its contents to an elevated temperature to melt the brazing alloy and to expand the pellets to their maximum dimensions under predetermined operating conditions thereby automatically positioning the spacing members along the tube, and finally cooling the tube to room temperature whereby the spacing disks become permanently fixed at their edges in the brazing alloy and define a hermetically sealed compartment for each fl group of fuel pellets. Upon cooling, the pellets contract thus leaving a space to accommodate thermal expansion of the pellets when in use in a reactor. The spacing members also provide lateral support for the tubular cladding to prevent collapse thereof when subjected to a reactor environment. (AEC)

  7. Investigation of low cost, high reliability sealing techniques for hybrid microcircuits, phase 1

    NASA Technical Reports Server (NTRS)

    Perkins, K. L.; Licari, J. J.

    1976-01-01

    A preliminary investigation was made to determine the feasibility of using adhesive package sealing for hybrid microcircuits. Major effort consisted of: (1) surveying representative hybrid manufacturers to assess the current use of adhesives for package sealing; (2) making a cost comparison of metallurgical versus adhesive package sealing; (3) determining the seal integrity of gold plated flatpack type packages sealed with selected adhesives, thermal shock, temperature cycling, mechanical shock, and constant acceleration test environments; and (4) defining a more comprehensive study to continue the evaluation of adhesives for package sealing. Results showed that 1.27 cm square gold plated flatpack type packages sealed with the film adhesives and the paste adhesive retained their seal integrity after all tests, and that similarly prepared 2.54 cm square packages retained their seal integrity after all tests except the 10,000 g's constant acceleration test. It is concluded that these results are encouraging, but by no means sufficient to establish the suitability of adhesives for sealing high reliability hybrid microcircuits.

  8. 76 FR 46808 - General Services Administration Acquisition Regulation; Submission for OMB Review; Sealed Bidding

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-03

    ... comments on or before: September 2, 2011. FOR FURTHER INFORMATION CONTACT: Michael O. Jackson, Procurement Analyst, Contract Policy Branch, at telephone (202) 208-4949 or michaelo.jackson@gsa.gov . ADDRESSES...

  9. Ceramic high pressure gas path seal

    NASA Technical Reports Server (NTRS)

    Liotta, G. C.

    1987-01-01

    Stage 1 ceramic shrouds (high pressure turbine gas path seal) were developed for the GE T700 turbine helicopter engine under the Army/NASA Contract NAS3-23174. This contract successfully proved the viability and benefits of a Stage 1 ceramic shroud for production application. Stage 1 ceramic shrouds were proven by extensive component and engine testing. This Stage 1 ceramic shroud, plasma sprayed ceramic (ZrOs-BY2O3) and bond coating (NiCrAlY) onto a cast metal backing, offers significant engine performance improvement. Due to the ceramic coating, the amount of cooling air required is reduced 20% resulting in a 0.5% increase in horsepower and a 0.3% decrease in specific fuel consumption. This is accomplished with a component which is lower in cost than the current production shroud. Stage 1 ceramic shrouds will be introduced into field service in late 1987.

  10. NAVAIR Progress in Assessing, Validating and Implementing Non-Chromate Primers (Briefing charts)

    DTIC Science & Technology

    2011-02-09

    logistics for any new coating or coating system NAVAIR Application Areas for Hexavalent Chromium Alternatives: Status Components/ Structure... Hexavalent chromium alternatives Sacrificial Coating Post Treatment MIL-A-8625 Anodize Avionics/ Electronics Magnesium/Titanium Conversion Aluminum Anodizing...Aluminum Pretreatment Type IC Seal Type IIB Seal Type II Seal Phosphating Rinse (Aluminum)Rinse (Steel) Cadmium Zinc-Nickel Aluminum Bonding Chrome

  11. Development of braided fiber seals for engine applications

    NASA Technical Reports Server (NTRS)

    Cai, Zhong; Mutharasan, Rajakkannu; Ko, Frank K.; Du, Guang-Wu; Steinetz, Bruce M.

    1993-01-01

    A new type of braided fiber seal was developed for high temperature engine applications. Development work performed includes seal design, fabrication, leakage flow testing, and flow resistance modeling. This new type of seal utilizes the high flow resistance of tightly packed fibers and the conformability of textile structures. The seal contains a core part with aligned fibers, and a sheath with braided fiber layers. Seal samples are made by using the conventional braiding process. Leakage flow measurements are then performed. Mass flow rate versus the simulated engine pressure and preload pressure is recorded. The flow resistance of the seal is analyzed using the Ergun equation for flow through porous media, including both laminar and turbulent effects. The two constants in the Ergun equation are evaluated for the seal structures. Leakage flow of the seal under the test condition is found to be in the transition flow region. The analysis is used to predict the leakage flow performance of the seal with the determined design parameters.

  12. Wear of seal materials used in aircraft propulsion systems

    NASA Technical Reports Server (NTRS)

    Bill, R. C.; Ludwig, L. P.

    1978-01-01

    The various types of seal locations in a gas turbine engine are described, and the significance of wear to each type is reviewed. Starting with positive contact shaft seals, existing material selection guidelines are reviewed, and the existing PV (contact pressure X sliding velocity) criteria for selecting seal materials are discussed, along with the theoretical background for these criteria. Examples of wear mechanisms observed to operate in positive contact seals are shown. Design features that can extend the operating capabilities of positive contact seals, including pressure balancing and incorporation of hydrodynamic lift are briefly discussed. It is concluded that, despite the benefits arising from these design features, improved positive contact seal materials from the standpoint of wear, erosion and oxidation resistance will be necessary for further improvements in seal performance and durability, and to meet stringent future challenges.

  13. A Study on Rotordynamic Characteristics of Swirl Brakes for Three Types of Seals

    NASA Astrophysics Data System (ADS)

    Xu, Wanjun; Yang, Jiangang

    2017-03-01

    In order to understand swirl brakes mechanisms and their influence on rotordynamic characteristics for different types of seals, a three-dimensional flow numerical simulation was presented. Three typical seals including labyrinth seal, fully partitioned damper seal and hole-pattern seal were compared under three inlet conditions of no preswirl, preswirl and preswirl with swirl brakes. FAN boundary condition was used to provide inlet preswirl. A modified identification method of effective damping was proposed. Feasibility of the swirl brakes on improving performance of damper seals was discussed. The results show that the swirl brakes influence the seal stability characteristics with whirl frequency. For the labyrinth seal the swirl brakes reverse the sign of effective damping at low frequency and improve the seal stability performance in a wide frequency range. The swirl brakes also improve the damper seals’ stability performance by increasing the low frequency effective damping and reducing their crossover frequency. Further results indicate the swirl brakes affect the rotational direction of the maximum (minimum) pressure positions and enhance the stability of the seals by reducing tangential force in each cavity.

  14. Ohio Route 50 joint sealant experiment : research implementation plan.

    DOT National Transportation Integrated Search

    2005-05-01

    Research in the state of Wisconsin over the past forty years has found no noticeable difference in : performance between jointed concrete pavement (JCP) constructed with a sealed contraction joint and : JCP constructed with a single, narrow, unsealed...

  15. A Comparison of Candidate Seal Designs for Future Docking Systems

    NASA Technical Reports Server (NTRS)

    Dunlap, Patrick, H., Jr.; Steinetz, Bruce, M.

    2012-01-01

    NASA is developing a new docking system to support future space exploration missions to low Earth orbit, the Moon, and other destinations. A key component of this system is the seal at the main docking interface which inhibits the loss of cabin air once docking is complete. Depending on the mission, the seal must be able to dock in either a seal-on-flange or seal-on-seal configuration. Seal-on-flange mating would occur when a docking system equipped with a seal docks to a system with a flat metal flange. This would occur when a vehicle docks to a node on the International Space Station. Seal-on-seal mating would occur when two docking systems equipped with seals dock to each other. Two types of seal designs were identified for this application: Gask-O-seals and multi-piece seals. Both types of seals had a pair of seal bulbs to satisfy the redundancy requirement. A series of performance assessments and comparisons were made between the candidate seal designs indicating that they meet the requirements for leak rate and compression and adhesion loads under a range of operating conditions. Other design factors such as part count, integration into the docking system tunnel, seal-on-seal mating, and cost were also considered leading to the selection of the multi-piece seal design for the new docking system. The results of this study can be used by designers of future docking systems and other habitable volumes to select the seal design best-suited for their particular application.

  16. 75 FR 29466 - Airworthiness Directives; Gulfstream Aerospace LP (Type Certificate Previously Held by Israel...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-26

    ... baggage compartment rubber seals, and replacing the baggage compartment rubber seals manufactured by Gumiyan with seals manufactured by Rubbercraft. Since the proposed AD was issued, we have received new... manufacturer of the baggage compartment rubber seals, and replacing the baggage compartment rubber seals...

  17. 40 CFR Table 26 to Subpart G of... - Seal Related Factors for Internal Floating Roof Vessels

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 9 2011-07-01 2011-07-01 false Seal Related Factors for Internal..., and Wastewater Pt. 63, Subpt. G, Table 26 Table 26 to Subpart G of Part 63—Seal Related Factors for Internal Floating Roof Vessels Seal type KS n Liquid mounted resilient seal: Primary seal only 3.0 0 With...

  18. 40 CFR Table 26 to Subpart G of... - Seal Related Factors for Internal Floating Roof Vessels

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 9 2010-07-01 2010-07-01 false Seal Related Factors for Internal..., and Wastewater Pt. 63, Subpt. G, Table 26 Table 26 to Subpart G of Part 63—Seal Related Factors for Internal Floating Roof Vessels Seal type KS n Liquid mounted resilient seal: Primary seal only 3.0 0 With...

  19. Fluorocarbon seal replaces metal piston ring in low density gas environment

    NASA Technical Reports Server (NTRS)

    Morath, W. D.; Morgan, N. E.

    1967-01-01

    Reinforced fluorocarbon cupseal, which provides an integral lip-type seal, replaces the metal piston rings in piston-cylinder configurations used in the compression of low density gases. The fluorocarbon seal may be used as cryogenic compressor piston seals.

  20. Performance oriented guidance for Mississippi chip seals - volume I.

    DOT National Transportation Integrated Search

    2013-12-01

    A five year laboratory study was conducted to investigate near surface properties of flexible pavements in relation to : how they are affected by bituminous surface treatments. Chip seals and scrub seals (a specialized type of chip seal) : were the f...

  1. 78 FR 70601 - International Mail Contract

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-26

    ... Notice of Filing Functionally Equivalent Agreement, November 15, 2013 (collectively, Notice). II. The... Service filed an application for non-public treatment of materials filed under seal (Attachment 1); a... agreement to one previously found to be functionally equivalent to the Inbound Market-Dominant Multi-Service...

  2. Presentation of computer code SPIRALI for incompressible, turbulent, plane and spiral grooved cylindrical and face seals

    NASA Technical Reports Server (NTRS)

    Walowit, Jed A.

    1994-01-01

    A viewgraph presentation is made showing the capabilities of the computer code SPIRALI. Overall capabilities of SPIRALI include: computes rotor dynamic coefficients, flow, and power loss for cylindrical and face seals; treats turbulent, laminar, Couette, and Poiseuille dominated flows; fluid inertia effects are included; rotor dynamic coefficients in three (face) or four (cylindrical) degrees of freedom; includes effects of spiral grooves; user definable transverse film geometry including circular steps and grooves; independent user definable friction factor models for rotor and stator; and user definable loss coefficients for sudden expansions and contractions.

  3. Selection of labyrinth seals in steam turbines

    NASA Astrophysics Data System (ADS)

    Kostyuk, A. G.

    2015-01-01

    The efficiency, vibration stability, operational durability, and cost of the main types of peripheral seals used in steam turbines are considered. A comparison between the conventional and honeycomb seals is given. Conditions subject to which replacement of conventional seals by honeycomb ones can be justified are pointed out. The use of variable-pitch multicomb seals as the most promising ones is recommended.

  4. 40 CFR Table 29 to Subpart G of... - Seal Related Factors for External Floating Roof Vessels

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 9 2011-07-01 2011-07-01 false Seal Related Factors for External..., and Wastewater Pt. 63, Subpt. G, Table 29 Table 29 to Subpart G of Part 63—Seal Related Factors for External Floating Roof Vessels Seal type Welded vessels KS N Riveted vessels KS N Metallic shoe seal...

  5. 40 CFR Table 29 to Subpart G of... - Seal Related Factors for External Floating Roof Vessels

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 9 2010-07-01 2010-07-01 false Seal Related Factors for External..., and Wastewater Pt. 63, Subpt. G, Table 29 Table 29 to Subpart G of Part 63—Seal Related Factors for External Floating Roof Vessels Seal type Welded vessels KS N Riveted vessels KS N Metallic shoe seal...

  6. 48 CFR 4.1202 - Solicitation provision and contract clause.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... REGULATION GENERAL ADMINISTRATIVE MATTERS Representations and Certifications 4.1202 Solicitation provision... Responsibility Matters. (g) 52.214-14, Place of Performance—Sealed Bidding. (h) 52.215-6, Place of Performance... Iran—Representation and Certification. (z) 52.226-2, Historically Black College or University and...

  7. 48 CFR 4.1202 - Solicitation provision and contract clause.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... REGULATION GENERAL ADMINISTRATIVE MATTERS Representations and Certifications 4.1202 Solicitation provision... Responsibility Matters. (g) 52.214-14, Place of Performance—Sealed Bidding. (h) 52.215-6, Place of Performance... Transactions Relating to Iran—Representation and Certifications. (z) 52.226-2, Historically Black College or...

  8. 48 CFR 4.1202 - Solicitation provision and contract clause.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... REGULATION GENERAL ADMINISTRATIVE MATTERS Representations and Certifications 4.1202 Solicitation provision... Responsibility Matters. (g) 52.214-14, Place of Performance—Sealed Bidding. (h) 52.215-6, Place of Performance..., Historically Black College or University and Minority Institution Representation. (aa) 52.227-6, Royalty...

  9. 46 CFR Sec. 3 - Terminal operating contract.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... _________, 19__, between the United States of America (herein called the “United States”), acting by and through...'s work under the provisions of this agreement the following: (1) For terminal services, an amount... first above written. (Seal) Attest: united states of america, department of transportation, maritime...

  10. 46 CFR Sec. 3 - Terminal operating contract.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... _________, 19__, between the United States of America (herein called the “United States”), acting by and through...'s work under the provisions of this agreement the following: (1) For terminal services, an amount... first above written. (Seal) Attest: united states of america, department of transportation, maritime...

  11. Actuator device utilizing a conductive polymer gel

    DOEpatents

    Chinn, Douglas A.; Irvin, David J.

    2004-02-03

    A valve actuator based on a conductive polymer gel is disclosed. A nonconductive housing is provided having two separate chambers separated by a porous frit. The conductive polymer is held in one chamber and an electrolyte solution, used as a source of charged ions, is held in the second chamber. The ends of the housing a sealed with a flexible elastomer. The polymer gel is further provide with electrodes with which to apply an electrical potential across the gel in order to initiate an oxidation reaction which in turn drives anions across the porous frit and into the polymer gel, swelling the volume of the gel and simultaneously contracting the volume of the electrolyte solution. Because the two end chambers are sealed the flexible elastomer expands or contracts with the chamber volume change. By manipulating the potential across the gel the motion of the elastomer can be controlled to act as a "gate" to open or close a fluid channel and thereby control flow through that channel.

  12. Viscoelastic analysis of seals for extended service life

    NASA Technical Reports Server (NTRS)

    Bower, Mark V.

    1993-01-01

    The space station is being developed for a service life of up to thirty years. As a consequence, the design requirements for the seals to be used are unprecedented. Full scale testing to assure the selected seals can satisfy the design requirements are not feasible. As an alternative, a sub-scale test program (2) has been developed by MSFC to calibrate the analysis tools to be used to certify the proposed design. This research has been conducted in support of the MSFC Integrated Seal Test Program. The ultimate objective of this research is to correlate analysis and test results to qualify the analytical tools which in turn, are to be used to qualify the flight hardware. Seals are simple devices, in wide spread use. The most common type of seal is the O-ring. O-ring seals are typically rings of rubber with a circular cross section. The rings are placed between the surfaces to be sealed, usually in a groove of some design. The particular design may differ based on a number of different factors. This research is focused on O-rings that are staticly compressed by perpendicular clamping forces, commonly referred to as face seals. In this type of seal the O-ring is clamped between the sealing surfaces by loads perpendicular to the circular cross section.

  13. Lithofacies and Diagenetic Controls on Formation-scale Mechanical, Transport, and Sealing Behavior of Caprocks: A Case Study of the Morrow shale and Thirteen Finger Limestone, Farnsworth Unit, Texas

    NASA Astrophysics Data System (ADS)

    Trujillo, N. A.; Heath, J. E.; Mozley, P.; Dewers, T. A.; Cather, M.

    2016-12-01

    Assessment of caprock sealing behavior for secure CO2 storage is a multiscale endeavor. Sealing behavior arises from the nano-scale capillarity of pore throats, but sealing lithologies alone do not guarantee an effective seal since bypass systems, such as connected, conductive fractures can compromise the integrity of the seal. We apply pore-to-formation-scale data to characterize the multiscale caprock sealing behavior of the Morrow shale and Thirteen Finger Limestone. This work is part of the Southwest Regional Partnership on Carbon Sequestration's Phase III project at the Farnsworth Unit, Texas. The caprock formations overlie the Morrow sandstone, the target for enhanced oil recovery and injection of over one million metric tons of anthropogenically-sourced CO2. Methods include: focused ion beam-scanning electron microscopy; laser scanning confocal microscopy; electron and optical petrography; multi-stress path mechanical testing and constitutive modeling; core examinations of sedimentary structures and fractures; and a noble gas profile for formation-scale transport of the sealing lihologies and the reservoir. We develop relationships between diagenetic characteristics of lithofacies to mechanical and petrophysical measurements of the caprocks. The results are applied as part of a caprock sealing behavior performance assessment. Funding for this project is provided by the U.S. Department of Energy's National Energy Technology Laboratory through the Southwest Regional Partnership on Carbon Sequestration (SWP) under Award No. DE-FC26-05NT42591. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

  14. The Way Ahead For Maritime UAVS

    DTIC Science & Technology

    2006-10-23

    of possible contract winners including Scan Eagle, Silver Fox, Wasp, Coyote and the USMC Tier I winner Dragon Eye. Technical data for these UAVs are...Neptune’s engine and avionics are placed above the waterline and the airframe is sealed for flotation as well as providing corrosion/water intrusion

  15. Mechanical seal having a single-piece, perforated mating ring

    DOEpatents

    Khonsari, Michael M [Baton Rouge, LA; Somanchi, Anoop K [Fremont, CA

    2007-08-07

    A mechanical seal (e.g., single mechanical seals, double mechanical seals, tandem mechanical seals, bellows, pusher mechanical seals, and all types of rotating and reciprocating machines) with reduced contact surface temperature, reduced contact surface wear, or increased life span. The mechanical seal comprises a rotating ring and a single-piece, perforated mating ring, which improves heat transfer by controllably channeling coolant flow through the single-piece mating ring such that the coolant is in substantially uniform thermal contact with a substantial portion of the interior surface area of the seal face, while maintaining the structural integrity of the mechanical seal and minimizing the potential for coolant flow interruptions to the seal face caused by debris or contaminants (e.g., small solids and trash) in the coolant.

  16. Some Numerical Simulations and an Experimental Investigation of Finger Seals

    NASA Technical Reports Server (NTRS)

    Braun, Minel J.; Smith, Ian; Marie, Hazel

    2007-01-01

    All seal types have been shown to lift effectively, and experience only minor wear during startup. .. The double pad design outperforms previous seals, providing lower operating temperatures, and less leakage at higher pressures. .. Future experimentation at higher pressures, temperatures, and operating speeds will show the full potential of finger sealing technology.

  17. Repair of through thickness corrosion/leaking defects in corroded pipelines using Fiber Reinforced Polymer overwrap

    NASA Astrophysics Data System (ADS)

    Nitheesh Kumar, P.; Khan, Vishwas Chandra; Balaganesan, G.; Pradhan, A. K.; Sivakumar, M. S.

    2018-04-01

    The present study is concerned with the repair of through thickness corrosion or leaking defects in metallic pipelines using a commercially available metallic seal and glass/epoxy composite. Pipe specimens are made with three different types of most commonly occurring through thickness corrosion/leaking defects. The metallic seal is applied over the through thickness corrosion/leaking defect and it is reinforced with glass/epoxy composite overwrap. The main objective of the metallic seal is to arrest the leak at live pressure. After reinforcing the metallic seal with glass/epoxy composite overwrap, the repaired composite wrap is able to sustain high pressures. Burst test is performed for different configurations of metallic seal and optimum configuration of metallic seal is determined. The optimum configurations of metallic seal for three different types of through thickness corrosion/leaking defects are further reinforced with glass/epoxy composite wrap and experimental failure pressure is determined by performing the burst test. An analytical model as per ISO 24817 has been developed to validate experimental results.

  18. Skew resisting hydrodynamic seal

    DOEpatents

    Conroy, William T.; Dietle, Lannie L.; Gobeli, Jeffrey D.; Kalsi, Manmohan S.

    2001-01-01

    A novel hydrodynamically lubricated compression type rotary seal that is suitable for lubricant retention and environmental exclusion. Particularly, the seal geometry ensures constraint of a hydrodynamic seal in a manner preventing skew-induced wear and provides adequate room within the seal gland to accommodate thermal expansion. The seal accommodates large as-manufactured variations in the coefficient of thermal expansion of the sealing material, provides a relatively stiff integral spring effect to minimize pressure-induced shuttling of the seal within the gland, and also maintains interfacial contact pressure within the dynamic sealing interface in an optimum range for efficient hydrodynamic lubrication and environment exclusion. The seal geometry also provides for complete support about the circumference of the seal to receive environmental pressure, as compared the interrupted character of seal support set forth in U.S. Pat. Nos. 5,873,576 and 6,036,192 and provides a hydrodynamic seal which is suitable for use with non-Newtonian lubricants.

  19. Multiscale Multiphysics Caprock Seal Analysis: A Case Study of the Farnsworth Unit, Texas, USA

    NASA Astrophysics Data System (ADS)

    Heath, J. E.; Dewers, T. A.; Mozley, P.

    2015-12-01

    Caprock sealing behavior depends on coupled processes that operate over a variety of length and time scales. Capillary sealing behavior depends on nanoscale pore throats and interfacial fluid properties. Larger-scale sedimentary architecture, fractures, and faults may govern properties of potential "seal-bypass" systems. We present the multiscale multiphysics investigation of sealing integrity of the caprock system that overlies the Morrow Sandstone reservoir, Farnsworth Unit, Texas. The Morrow Sandstone is the target injection unit for an on-going combined enhanced oil recovery-CO2 storage project by the Southwest Regional Partnership on Carbon Sequestration (SWP). Methods include small-to-large scale measurement techniques, including: focused ion beam-scanning electron microscopy; laser scanning confocal microscopy; electron and optical petrography; core examinations of sedimentary architecture and fractures; geomechanical testing; and a noble gas profile through sealing lithologies into the reservoir, as preserved from fresh core. The combined data set is used as part of a performance assessment methodology. The authors gratefully acknowledge the U.S. Department of Energy's (DOE) National Energy Technology Laboratory for sponsoring this project through the SWP under Award No. DE-FC26-05NT42591. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

  20. Experimental Evaluation of Cement Replacement Fillers on the Performance of Slurry Seal

    NASA Astrophysics Data System (ADS)

    Fakhri, Mansour; Alrezaei, Hossein Ali; Naji Almasi, Soroush

    2016-10-01

    Reducing the level of roads service is a process that starts from the first day of the operation of road and the slope of deterioration curve of road sustainability becomes faster with the passage of time. After building the road, adopting an economic approach in order to maintain the road is very important. Slurry seal as one type of protective asphalts that works by sealing inactive cracks of the road and increasing skid resistance is the most effective types of restoration with environmentally friendly behaviour. Fillers are responsible for adjusting set time in slurry seal. Cement is the most common filler used in slurry seal. Cements having suitable properties as a filler, has a very energy demanding manufacturing process and a notable amount of energy is used for manufacturing cement in the country annually. On the other hand, manufacturing process and application of cement have increased levels of pollutant gases, followed by significant environmental pollution. So in this study other options as a filler such as hydrated lime, stone powder and the slag from iron melting furnace were compared with two common types of cement (Portland and type-v cement) in the mixtures of slurry seal by wet abrasion and cohesion tests. Results indicated that, in both tests, lime and slag fillers had behaviours close to the cement filler.

  1. Tracking sources of Clostridium botulinum type E contamination in seal meat.

    PubMed

    Leclair, Daniel; Farber, Jeffrey M; Pagotto, Franco; Suppa, Sandy; Doidge, Bill; Austin, John W

    2017-01-01

    Botulism in Nunavik, Quebec is associated with the consumption of aged marine mammal meat and fat. The objective was to identify meat handling practices presenting a risk of contamination of seal meat with C. botulinum. Potential sources of contamination were assessed through interviews with igunaq producers from five communities of Nunavik. These sources were verified by detection and isolation of C. botulinum from igunaq prepared in the field from seal carcasses. Interviews indicated practices presenting a risk for contamination included: placing meat or fat on coastal rocks, using seawater for rinsing, and ageing meat in inverted seal skin pouches. Although the presence of C. botulinum type E spores was detected in only two of 32 (6.3%) meat or fat samples collected during the butchering process, two of four igunaq preparations from these samples contained type E botulinum toxin. Analysis of C. botulinum type E isolates recovered from these preparations indicated that shoreline soil may be a source of contamination. Seal meat and fat may be contaminated with C. botulinum type E during the butchering process. Measures can be adopted to reduce the risks of contamination in the field and possibly decrease the incidence of type E botulism in Nunavik.

  2. 36 CFR 223.88 - Bidding methods.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 36 Parks, Forests, and Public Property 2 2013-07-01 2013-07-01 false Bidding methods. 223.88... Sale Contracts Advertisement and Bids § 223.88 Bidding methods. (a) Competitive sales of National Forest timber shall be offered through either sealed or oral auction bidding. The method chosen for each...

  3. 36 CFR 223.88 - Bidding methods.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 36 Parks, Forests, and Public Property 2 2012-07-01 2012-07-01 false Bidding methods. 223.88... Sale Contracts Advertisement and Bids § 223.88 Bidding methods. (a) Competitive sales of National Forest timber shall be offered through either sealed or oral auction bidding. The method chosen for each...

  4. 36 CFR 223.88 - Bidding methods.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 36 Parks, Forests, and Public Property 2 2014-07-01 2014-07-01 false Bidding methods. 223.88... Sale Contracts Advertisement and Bids § 223.88 Bidding methods. (a) Competitive sales of National Forest timber shall be offered through either sealed or oral auction bidding. The method chosen for each...

  5. 36 CFR 223.88 - Bidding methods.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 36 Parks, Forests, and Public Property 2 2011-07-01 2011-07-01 false Bidding methods. 223.88... Sale Contracts Advertisement and Bids § 223.88 Bidding methods. (a) Competitive sales of National Forest timber shall be offered through either sealed or oral auction bidding. The method chosen for each...

  6. 48 CFR 52.214-10 - Contract Award-Sealed Bidding.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... the solicitation, will be most advantageous to the Government considering only price and the price... quantities less than those specified. The Government reserves the right to make an award on any item for a quantity less than the quantity offered, at the unit prices offered, unless the bidder specifies otherwise...

  7. 48 CFR 4.502 - Policy.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... MATTERS Electronic Commerce in Contracting 4.502 Policy. (a) The Federal Government shall use electronic commerce whenever practicable or cost-effective. The use of terms commonly associated with paper transactions (e.g., “copy,” “document,” “page,” “printed,” “sealed envelope,” and “stamped”) shall not be...

  8. Feasibility Assessment of Thermal Barrier Seals for Extreme Transient Temperatures

    NASA Technical Reports Server (NTRS)

    Steinetz, Bruce M.; Dunlap, Patrick H., Jr.

    1998-01-01

    The assembly joints of modem solid rocket motor cases are generally sealed using conventional O-ring type seals. The 5500+ F combustion gases produced by rocket motors are kept a safe distance away from the seals by thick layers of phenolic insulation. Special compounds are used to fill insulation gaps leading up to the seals to prevent a direct flowpath to them. Design criteria require that the seals should not experience torching or charring during operation, or their sealing ability would be compromised. On limited occasions, NASA has observed charring of the primary O-rings of the Space Shuttle solid rocket nozzle assembly joints due to parasitic leakage paths opening up in the gap-fill compounds during rocket operation. NASA is investigating different approaches for preventing torching or charring of the primary O-rings. One approach is to implement a braided rope seal upstream of the primary O-ring to serve as a thermal barrier that prevents the hot gases from impinging on the O-ring seals. This paper presents flow, resiliency, and thermal resistance for several types of NASA rope seals braided out of carbon fibers. Burn tests were performed to determine the time to burn through each of the seals when exposed to the flame of an oxyacetylene torch (5500 F), representative of the 5500 F solid rocket motor combustion temperatures. Rope seals braided out of carbon fibers endured the flame for over six minutes, three times longer than solid rocket motor burn time. Room and high temperature flow tests are presented for the carbon seals for different amounts of linear compression. Room temperature compression tests were performed to assess seal resiliency and unit preloads as a function of compression. The thermal barrier seal was tested in a subscale "char" motor test in which the seal sealed an intentional defect in the gap insulation. Temperature measurements indicated that the seal blocked 2500 F combustion gases on the upstream side with very little temperature rise on the downstream side.

  9. LEAKAGE CHARACTERISTICS OF MULTI-CONDUCTOR CABLES AND CONDUIT SEALS

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

    Nelson, C.; Becker, S.

    1962-12-12

    Pipe threads in conduit seal-offs can be made air tight by use of a two- part thiokol-epoxy sealant such as Sika.'' This material bonds to metal but does not harden; thus, threaded parts can be separated. Gas seals in conduit sealoffs can be made by use of Chico, Type A'' sealant. This material is hard and can withstand high pressure differentials. However, there is a detectable leakage through Chico, Type A.'' Sika'' can be used to make a suitable gas- tight seal. However, this material is flexible and will not support long cable lengths. A dual pour method is suggestedmore » of first casting Chico'' around the connectors to obtain strength in the seal and then using either Sika'' or Micro-Preg'' to produce a tight seal. Leakage through the cable, between strands of conductor, can be reduced by either soldering the ends or dipping the ends in conductive epoxy paint. (auth)« less

  10. Turbomachinery Clearance Control

    NASA Technical Reports Server (NTRS)

    Chupp, Raymond E.; Hendricks, Robert C.; Lattime, Scott B.; Steinetz, Bruce M.; Aksit, Mahmut F.

    2007-01-01

    Controlling interface clearances is the most cost effective method of enhancing turbomachinery performance. Seals control turbomachinery leakages, coolant flows and contribute to overall system rotordynamic stability. In many instances, sealing interfaces and coatings are sacrificial, like lubricants, giving up their integrity for the benefit of the component. They are subjected to abrasion, erosion, oxidation, incursive rubs, foreign object damage (FOD) and deposits as well as extremes in thermal, mechanical, aerodynamic and impact loadings. Tribological pairing of materials control how well and how long these interfaces will be effective in controlling flow. A variety of seal types and materials are required to satisfy turbomachinery sealing demands. These seals must be properly designed to maintain the interface clearances. In some cases, this will mean machining adjacent surfaces, yet in many other applications, coatings are employed for optimum performance. Many seals are coating composites fabricated on superstructures or substrates that are coated with sacrificial materials which can be refurbished either in situ or by removal, stripping, recoating and replacing until substrate life is exceeded. For blade and knife tip sealing an important class of materials known as abradables permit blade or knife rubbing without significant damage or wear to the rotating element while maintaining an effective sealing interface. Most such tip interfaces are passive, yet some, as for the high-pressure turbine (HPT) case or shroud, are actively controlled. This work presents an overview of turbomachinery sealing. Areas covered include: characteristics of gas and steam turbine sealing applications and environments, benefits of sealing, types of standard static and dynamics seals, advanced seal designs, as well as life and limitations issues.

  11. Measurement of behavior of secondary sealing areas of rotary engine apex seals - Two-piece nonsplit and three-piece slanted horizontal split types

    NASA Astrophysics Data System (ADS)

    Matsuura, Kenji; Terasaki, Kazuo; Yamane, Katsuki

    1992-12-01

    Behavior measurements have been made with two displacement sensors and an underseal pressure sensor, using an overhanging eccentric shaft-type single-rotor research engine equipped with a packaged multichannel slip ring. The two-piece seal was tilted to the leading and trailing sides of a seal slot during its travel along the rotor housing surface and vibrated on the top end of the leading side of the slot as a fulcrum after the shift from the trailing to the leading side of the slot after the minor axis on the spark plug side. As for the three-piece seal, its top part was also tilted in all operating conditions, although its bottom part made effective area contact with the side of the slot under light load conditions up to medium engine speeds. The working chamber pressure was induced in the underseal in the same manner as with the two-piece type.

  12. Small High-Speed Self-Acting Shaft Seals for Liquid Rocket Engines

    NASA Technical Reports Server (NTRS)

    Burcham, R. E.; Boynton, J. L.

    1977-01-01

    Design analysis, fabrication, and experimental evaluation were performed on three self-acting facetype LOX seal designs and one circumferential-type helium deal design. The LOX seals featured Rayleigh step lift pad and spiral groove geometry for lift augmentation. Machined metal bellows and piston ring secondary seal designs were tested. The helium purge seal featured floating rings with Rayleigh step lift pads. The Rayleigh step pad piston ring and the spiral groove LOX seals were successfully tested for approximately 10 hours in liquid oxygen. The helium seal was successfully tested for 24 hours. The shrouded Rayleigh step hydrodynamic lift pad LOX seal is feasible for advanced, small, high-speed oxygen turbopumps.

  13. The cool seal system: a practical solution to the shaft seal problem and heat related complications with implantable rotary blood pumps.

    PubMed

    Yamazaki, K; Mori, T; Tomioka, J; Litwak, P; Antaki, J F; Tagusari, O; Koyanagi, H; Griffith, B P; Kormos, R L

    1997-01-01

    A critical issue facing the development of an implantable, rotary blood pump is the maintenance of an effective seal at the rotating shaft. Mechanical seals are the most versatile type of seal in wide industrial applications. However, in a rotary blood pump, typical seal life is much shorter than required for chronic support. Seal failure is related to adhesion and aggregation of heat denatured blood proteins that diffuse into the lubricating film between seal faces. Among the blood proteins, fibrinogen plays an important role due to its strong propensity for adhesion and low transition temperature (approximately 50 degrees C). Once exposed to temperature exceeding 50 degrees C, fibrinogen molecules fuse together by multi-attachment between heat denatured D-domains. This quasi-polymerized fibrin increases the frictional heat, which proliferates the process into seal failure. If the temperature of the seal faces is maintained well below 50 degrees C, a mechanical seal would not fail in blood. Based on this "Cool-Seal" concept, we developed a miniature mechanical seal made of highly thermally conductive material (SiC), combined with a recirculating purge system. A large supply of purge fluid is recirculated behind the seal face to augment convective heat transfer to maintain the seal temperature below 40 degrees C. It also cools all heat generating pump parts (motor coil, bearing, seal). The purge consumption has been optimized to virtually nil (< 0.5 cc/day). An ultrafiltration unit integrated in the recirculating purge system continuously purifies and sterilizes the purge fluid for more than 5 months without filter change. The seal system has now been incorporated into our intraventricular axial flow blood pump (IVAP) and newly designed centrifugal pump. Ongoing in vivo evaluation of these systems has demonstrated good seal integrity for more than 160 days. The Cool-Seal system can be applied to any type of rotary blood pump (axial, diagonal, centrifugal, etc.) and offers a practical solution to the shaft seal problem and heat related complications, which currently limit the use of implantable rotary blood pumps.

  14. Influence of moisture on the apical seal of root canal fillings with five different types of sealer.

    PubMed

    Roggendorf, Matthias Johannes; Ebert, Johannes; Petschelt, Anselm; Frankenberger, Roland

    2007-01-01

    The aim of this study was to evaluate the influence of moisture on apical leakage using five different types of sealer. There were 120 single-rooted teeth instrumented to .02/#60 and randomly assigned to 10 experimental groups, one control group (AH Plus, lateral condensation) (n = 10) or positive/negative controls (n = 5). Before obturation teeth were dried thoroughly, followed by recontamination with moisture in a wet chamber (moist groups; 37 degrees C for 7 days). The teeth of the experimental groups (a, dry; b, moist) were obturated with sealer (groups 1, AH Plus; 2, Apexit; 3, Ketac-Endo; 4, RoekoSeal; 5, Tubli-Seal) and a single gutta-percha cone .02/#55. Teeth were centrifuged (30 x g for 3 minutes) in 5% methylene blue. Linear dye penetration was measured under a stereomicroscope. Moisture led to less microleakage for Apexit, RoekoSeal, and Tubli-Seal and higher values for AH Plus and Ketac-Endo. Multifactorial ANOVA displayed a significant dependence of leakage on sealer (p < 0.001) and the combination sealer or moisture (p < 0.01). It depends on the sealer type in which way moisture affects the apical seal.

  15. Sealing Penetrating Eye Injuries with Photoactivated Bonding

    DTIC Science & Technology

    2012-09-01

    light treatment parameters for sealing a variety of penetrating eye wounds and have demonstrated that these repair procedures are safe to ocular...AWARD NUMBER: W81XWH-09-2-0050 TITLE: Sealing Penetrating Eye Injuries with Photoactivated...TYPE Final 3. DATES COVERED (From - To) 1 Sep 2009-31 Aug 2012 4. TITLE AND SUBTITLE Sealing Penetrating Eye Injuries with Photoactivated Bonding

  16. Mechanical seal having a double-tier mating ring

    DOEpatents

    Khonsari, Michael M.; Somanchi, Anoop K.

    2005-09-13

    An apparatus and method to enhance the overall performance of mechanical seals in one of the following ways: by reducing seal face wear, by reducing the contact surface temperature, or by increasing the life span of mechanical seals. The apparatus is a mechanical seal (e.g., single mechanical seals, double mechanical seals, tandem mechanical seals, bellows, pusher mechanical seals, and all types of rotating and reciprocating machines) comprising a rotating ring and a double-tier mating ring. In a preferred embodiment, the double-tier mating ring comprises a first and a second stationary ring that together form an agitation-inducing, guided flow channel to allow for the removal of heat generated at the seal face of the mating ring by channeling a coolant entering the mating ring to a position adjacent to and in close proximity with the interior surface area of the seal face of the mating ring.

  17. Toward an Improved Hypersonic Engine Seal

    NASA Technical Reports Server (NTRS)

    Dunlap, Patrick H., Jr.; Steinetz, Bruce M.; DeMange,Jeffrey J.; Taylor, Shawn C.

    2003-01-01

    High temperature, dynamic seals are required in advanced engines to seal the perimeters of movable engine ramps for efficient, safe operation in high heat flux environments at temperatures from 2000 to 2500 F. Current seal designs do not meet the demanding requirements for future engines, so NASA s Glenn Research Center (GRC) is developing advanced seals to overcome these shortfalls. Two seal designs and two types of seal preloading devices were evaluated in a series of compression tests at room temperature and 2000 F and flow tests at room temperature. Both seals lost resiliency with repeated load cycling at room temperature and 2000 F, but seals with braided cores were significantly more flexible than those with cores composed of uniaxial ceramic fibers. Flow rates for the seals with cores of uniaxial fibers were lower than those for the seals with braided cores. Canted coil springs and silicon nitride compression springs showed promise conceptually as potential seal preloading devices to help maintain seal resiliency.

  18. Design criteria monograph on transmission seals

    NASA Technical Reports Server (NTRS)

    Hayden, T. S.; Keller, C. H., Jr.

    1975-01-01

    Guide is based on experience obtained in wide variety of applications using lip, circumferential, and face seals. Particular attention is given to capabilities and lubrication of various seal types. Special limitations as a result of storage requirements, quality control, installation, operation, and removal are discussed.

  19. 75 FR 47650 - International Product Change-Global Expedited Package Services-Non-Published Rates

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-06

    ... POSTAL SERVICE International Product Change--Global Expedited Package Services-- Non-Published...-Published Rates to the Competitive Products List pursuant to 39 U.S.C. 3642. DATES: August 6, 2010. FOR...-Published Rates to the Competitive Products List, and Notice of Filing (Under Seal) of Contract and Enabling...

  20. 48 CFR 4.502 - Policy.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... transactions (e.g., “copy,” “document,” “page,” “printed,” “sealed envelope,” and “stamped”) shall not be... transactions by using other media to meet the requirements of any contract action governed by the FAR (e.g..., shall ensure that systems, technologies, procedures, and processes used by the agency to conduct...

  1. 48 CFR 52.203-2 - Certificate of Independent Price Determination.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... offeror or competitor before bid opening (in the case of a sealed bid solicitation) or contract award (in the case of a negotiated solicitation) unless otherwise required by law; and (3) No attempt has been... for determining the prices being offered in this bid or proposal, and that the signatory has not...

  2. INFINITY construction contract signed

    NASA Image and Video Library

    2010-04-06

    Key state and community leaders celebrated April 6 with the signing of a construction contract for the state-of-the-art INFINITY Science Center planned near John C. Stennis Space Center in south Mississippi. Gulfport Mayor George Schloegel (l to r), chair of non-profit INFINITY Science Center Inc., was joined for the signing ceremony at the Hancock Bank in Gulfport by Virginia Wagner, sister of late Hancock Bank President Leo Seal Jr.; and Roy Anderson III, president and CEO of Roy Anderson Corp. Seal was the first chair of INFINITY Science Center Inc., which has led in development of the project. Roy Anderson Corp. plans to begin construction on the 72,000-square-foot, $28 million science and education center in May. The Mississippi Department of Transportation (MDOT) also is set to begin construction of a $2 million access road to the new center. The April 6 ceremony was attended by numerous officials, including former Stennis Space Center Directors Jerry Hlass and Roy Estess; Mississippi Senate President Pro Tempore Billy Hewes, R-Gulfport; Mississippi Rep. Diane Peranich, D-Pass Christian; and MDOT Southern District Commissioner Wayne Brown.

  3. INFINITY construction contract signed

    NASA Technical Reports Server (NTRS)

    2010-01-01

    Key state and community leaders celebrated April 6 with the signing of a construction contract for the state-of-the-art INFINITY Science Center planned near John C. Stennis Space Center in south Mississippi. Gulfport Mayor George Schloegel (l to r), chair of non-profit INFINITY Science Center Inc., was joined for the signing ceremony at the Hancock Bank in Gulfport by Virginia Wagner, sister of late Hancock Bank President Leo Seal Jr.; and Roy Anderson III, president and CEO of Roy Anderson Corp. Seal was the first chair of INFINITY Science Center Inc., which has led in development of the project. Roy Anderson Corp. plans to begin construction on the 72,000-square-foot, $28 million science and education center in May. The Mississippi Department of Transportation (MDOT) also is set to begin construction of a $2 million access road to the new center. The April 6 ceremony was attended by numerous officials, including former Stennis Space Center Directors Jerry Hlass and Roy Estess; Mississippi Senate President Pro Tempore Billy Hewes, R-Gulfport; Mississippi Rep. Diane Peranich, D-Pass Christian; and MDOT Southern District Commissioner Wayne Brown.

  4. Alternate seal configuration for lithium primary cells

    NASA Technical Reports Server (NTRS)

    Kelley, J. A.

    1982-01-01

    The problem of glass degradation in the glass-to-metal seals in lithium/sulfur dioxide cells is discussed. The glass degradation mechanism is attributed to lithium reacting with glass which is a result of deposition of lithium at the glass/metal/electrolyte interface. The worst degradation was observed when cells were stored in the inverted position. Alternate sealing methods were examined and a modified Ziegler seal is considered to be one of the best possible methods. The seal consists of a crimp type soft seal using a plastic annulus and a metal tube. Results of degradation tests are presented.

  5. Forming a Turbomachinery Seals Working Group - An Overview and Discussion

    NASA Technical Reports Server (NTRS)

    Proctor, Margaret P.

    2007-01-01

    A proposal to form a Turbomachinery Seals Working Group is discussed. Survey responses regarding the purpose, membership, and meeting frequency are presented as well as the areas of expertise and experience of the respondents. The types of seals used, designed, or sold, current work, and technical challenges of turbomachinery seals, their materials, analysis, geometry, manufacturing, maintenance, testing, and incorporation into engine systems are also presented.

  6. USAF Inorganic Coating Successes

    DTIC Science & Technology

    2012-08-01

    Sodium dichromate solution, 50 parts per million Benchmark Permanganate Seal Candidate 1 Low Nickel Seal (with a hot water seal) Candidate 2A Low...requested by OO-ALC • Continue assisting OO-ALC with implementing permanganate sealer – Received approval from Engineering Review Board (ERB...to use the permanganate seal for Type II anodizing operations • Position OO-ALC for a completely Cr-free surface finishing operation – Anodizing

  7. Engineering report. Part 1: NASA wheel air seal development for space shuttle type environmental requirements

    NASA Technical Reports Server (NTRS)

    1973-01-01

    The sealing techniques are studied for existing aircraft wheel-tire designs to meet the hard vacuum .00001 torr and cold temperature -65 F requirements of space travel. The investigation covers the use of existing wheel seal designs.

  8. Optical characterization of a light guide for the polymerization of root canal fillers: preliminary results

    NASA Astrophysics Data System (ADS)

    Munin, Egberto; Lupato Conrado, Luis A.; Alves, Leandro P.; Zangaro, Renato A.

    2004-05-01

    The sealing cements used in endodontics are commonly of the type activated by chemical reactions. During polymerization, mechanical contractions are not uncommon, leading to non-perfect sealing or treatment failure. Photopolymerizable cements usually presents superior performance as compared to those chemically activated. However, difficulties in carrying-up the light to difficult-to-reach regions like the dental apex preclude those material of being accepted in the dental office routine. Recently, a novel technique for the light curing of photopolymerizable cements in endodontic applications has been proposed. Such a technique makes use of a polymeric light guide to deliver the curing light to the apex region, for a single step polymerization of the canal filler. For this work, a 28 mm long polymer light-guide, has been produced. The polymer surface was roughened to produce light scattering and allow the light to escape from the guide. The light scattering profile along the body of the guide is an important property for the proposed application. We used an integrating sphere to measure the irradiation profile for the proposed endodontic device. It was found that the experimental data for the amount of light coupled into the integrating sphere as a function of the length of the cone inside the sphere fits to a double exponential model.

  9. A magnetic fluid seal for rotary blood pumps: effects of seal structure on long-term performance in liquid.

    PubMed

    Mitamura, Yoshinori; Takahashi, Sayaka; Amari, Shuichi; Okamoto, Eiji; Murabayashi, Shun; Nishimura, Ikuya

    2011-03-01

    A magnetic fluid (MF) seal enables mechanical contact-free rotation of the shaft and hence has excellent durability. The performance of an MF seal, however, has been reported to decrease in liquids. We developed an MF seal that has a "shield" mechanism, and a new MF with a higher magnetization of 47.9 kA/m. The sealing performance of the MF seal installed in a rotary blood pump was studied. Three types of MF seals were used. Seal A was a conventional seal without a shield. Seal B had the same structure as that of Seal A, but the seal was installed at 1 mm below liquid level. Seal C was a seal with a shield and the MF was set at 1 mm below liquid level. Seal A failed after 6 and 11 days. Seal B showed better results (20 and 73 days). Seal C showed long-term durability (217 and 275 days). The reason for different results in different seal structures was considered to be different flow conditions near the magnetic fluid. Fluid dynamics near the MF in the pump were analyzed using computational fluid dynamics (CFD) software. We have developed an MF seal with a shield that works in liquid for >275 days. The MF seal is promising as a shaft seal for rotary blood pumps.

  10. High speed, self-acting shaft seal. [for use in turbine engines

    NASA Technical Reports Server (NTRS)

    Ludwig, L. P.; Hady, W. F. (Inventor)

    1975-01-01

    A high-speed, self-acting circumferential type shaft seal for use in turbine engines is disclosed. One or more conventional circumferential ring seals having a central aperture are mounted in a housing. In three of the four embodiments of the invention, a helical groove and one or more dam seals are cut in the inner cylindrical surface of the one or more ring seals. In a fourth embodiment, two or more lift pads are disposed in surface contact with the inner cylindrical surface of the seal rings. To the outside of the lift pads, two dam seals are cut in the inner cylindrical surface of two of the ring seals. In each of the embodiments, a net outward radial force was produced during rotation of the turbine causing the ring seals to lift out of contact with the turbine shaft to minimize wear of the ring seals.

  11. Brush seal numerical simulation: Concepts and advances

    NASA Technical Reports Server (NTRS)

    Braun, M. J.; Kudriavtsev, V. V.

    1994-01-01

    The development of the brush seal is considered to be most promising among the advanced type seals that are presently in use in the high speed turbomachinery. The brush is usually mounted on the stationary portions of the engine and has direct contact with the rotating element, in the process of limiting the 'unwanted' leakage flows between stages, or various engine cavities. This type of sealing technology is providing high (in comparison with conventional seals) pressure drops due mainly to the high packing density (around 100 bristles/sq mm), and brush compliance with the rotor motions. In the design of modern aerospace turbomachinery leakage flows between the stages must be minimal, thus contributing to the higher efficiency of the engine. Use of the brush seal instead of the labyrinth seal reduces the leakage flow by one order of magnitude. Brush seals also have been found to enhance dynamic performance, cost less, and are lighter than labyrinth seals. Even though industrial brush seals have been successfully developed through extensive experimentation, there is no comprehensive numerical methodology for the design or prediction of their performance. The existing analytical/numerical approaches are based on bulk flow models and do not allow the investigation of the effects of brush morphology (bristle arrangement), or brushes arrangement (number of brushes, spacing between them), on the pressure drops and flow leakage. An increase in the brush seal efficiency is clearly a complex problem that is closely related to the brush geometry and arrangement, and can be solved most likely only by means of a numerically distributed model.

  12. High-temperature, long-life polyimide seals for hydraulic actuator rods

    NASA Technical Reports Server (NTRS)

    Johnson, R. L.; Lee, J.; Loomis, W. R.

    1971-01-01

    Two types of polyimide seals are developed for hydraulic actuator rod in low pressure second stage of two-stage configuration. Each seal melts test objectives of twenty million cycles of operation at 534 K. Analytical and experimental study results are discussed. Potential applications are given.

  13. Chemical laser exhaust pipe design research

    NASA Astrophysics Data System (ADS)

    Sun, Yunqiang; Huang, Zhilong; Chen, Zhiqiang; Ren, Zebin; Guo, Longde

    2016-10-01

    In order to weaken the chemical laser exhaust gas influence of the optical transmission, a vent pipe is advised to emissions gas to the outside of the optical transmission area. Based on a variety of exhaust pipe design, a flow field characteristic of the pipe is carried out by numerical simulation and analysis in detail. The research results show that for uniform deflating exhaust pipe, although the pipeline structure is cyclical and convenient for engineering implementation, but there is a phenomenon of air reflows at the pipeline entrance slit which can be deduced from the numerical simulation results. So, this type of pipeline structure does not guarantee seal. For the design scheme of putting the pipeline contract part at the end of the exhaust pipe, or using the method of local area or tail contraction, numerical simulation results show that backflow phenomenon still exists at the pipeline entrance slit. Preliminary analysis indicates that the contraction of pipe would result in higher static pressure near the wall for the low speed flow field, so as to produce counter pressure gradient at the entrance slit. In order to eliminate backflow phenomenon at the pipe entrance slit, concerned with the pipeline type of radial size increase gradually along the flow, flow field property in the pipe is analyzed in detail by numerical simulation methods. Numerical simulation results indicate that there is not reflow phenomenon at entrance slit of the dilated duct. However the cold air inhaled in the slit which makes the temperature of the channel wall is lower than the center temperature. Therefore, this kind of pipeline structure can not only prevent the leak of the gas, but also reduce the wall temperature. In addition, compared with the straight pipe connection way, dilated pipe structure also has periodic structure, which can facilitate system integration installation.

  14. Nozzle and shroud assembly mounting structure

    DOEpatents

    Faulder, Leslie J.; Frey, deceased, Gary A.; Nielsen, Engward W.; Ridler, Kenneth J.

    1997-01-01

    The present nozzle and shroud assembly mounting structure configuration increases component life and reduces maintenance by reducing internal stress between the mounting structure having a preestablished rate of thermal expansion and the nozzle and shroud assembly having a preestablished rate of thermal expansion being less than that of the mounting structure. The mounting structure includes an outer sealing portion forming a cradling member in which an annular ring member is slidably positioned. The mounting structure further includes an inner mounting portion to which a hooked end of the nozzle and shroud assembly is attached. As the inner mounting portion expands and contracts, the nozzle and shroud assembly slidably moves within the outer sealing portion.

  15. Nozzle and shroud assembly mounting structure

    DOEpatents

    Faulder, L.J.; Frey, G.A.; Nielsen, E.W.; Ridler, K.J.

    1997-08-05

    The present nozzle and shroud assembly mounting structure configuration increases component life and reduces maintenance by reducing internal stress between the mounting structure having a preestablished rate of thermal expansion and the nozzle and shroud assembly having a preestablished rate of thermal expansion being less than that of the mounting structure. The mounting structure includes an outer sealing portion forming a cradling member in which an annular ring member is slidably positioned. The mounting structure further includes an inner mounting portion to which a hooked end of the nozzle and shroud assembly is attached. As the inner mounting portion expands and contracts, the nozzle and shroud assembly slidably moves within the outer sealing portion. 3 figs.

  16. Experiences with welding multi-assembly sealed baskets at Palisades

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

    Agace, S.; Worrell, S.; Stewart, L.

    1995-12-01

    Four utilities were using operational canister-based dry storage facilities at year-end, and seven more have contracts to establish similar facilities. Consumers Power`s Palisades Nuclear Power Plant has successfully completed loading its eighth dry storage canister with the Ventilated Storage Cask (VSC) system, under license to Sierra Nuclear Corporation. The VSC has a Multi-Assembly Sealed Basket (MSB) containing 24 specially-selected and aged spent fuel assemblies. MSB closure occurs when two independent lids are welded at the utility. The canister wall and lids are SA-516 Grade 70 carbon steel. This paper discusses the welding system design, closure operations and MSB closure operationsmore » at Palisades.« less

  17. Solid state switch panel. [determination of optimum transducer type for required switches

    NASA Technical Reports Server (NTRS)

    Beenfeldt, E.

    1973-01-01

    An intensive study of various forms of transducers was conducted with application towards hermetically sealing the transducer and all electronics. The results of the study indicated that the Hall effect devices and a LED/phototransistor combination were the most practical for this type of application. Therefore, hardware was developed utilizing a magnet/Hall effect transducer for single action switches and LED/phototransistor transducers for rotary multiposition or potentiometer applications. All electronics could be housed in a hermetically sealed compartment. A number of switches were built and models were hermetically sealed to prove the feasibility of this type of fabrication. One of each type of switch was subjected to temperature cycling, vibration, and EMI tests. The results of these tests are presented.

  18. Seals. Grades 3-6.

    ERIC Educational Resources Information Center

    New England Aquarium, Boston, MA.

    Explanations of a marine mammal rescue program and information on seals and sea lions are presented in this curriculum package for intermediate grade teachers. Activities are highlighted which focus on the natural history of harbor seals. This unit contains: (1) pre-trip activities (including fact sheets and worksheets on the different types of…

  19. Cf-252 Characterization Documents

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

    Feldman, Alexander

    2014-03-14

    Six documents were written by Vance and Associates under contract to the Off-Site Source Recovery Project of Los Alamos National Laboratory. These Six documents provided the basis for characterization of Californium-252 sealed sources and for the packaging and manifesting of this material for disposal at the Waste Isolation Pilot Project. The Six documents are: 1. VA-OSR-10, Development of radionuclide distributions for Cf-252 sealed sources. 2. VA-OSR-11, Uncertainty analysis for Cf-252 sealed sources. 3. VA-OSR-12, To determine the radionuclides in the waste drums containing Cf-252 sealed source waste that are required to be reported under the requirements of the WIPP WACmore » and the TRAMPAC. 4. VA-OSR-13, Development of the spreadsheet for the radiological calculations for the characterization of Cf-252 sources. 5. VA-OSR-14, Relative importance of neutron-induced fission in Cf-252 sources. 6. VA-OSR-15, Determine upper bound of decay product inventories from a drum of Cf-252 sources. These six documents provide the technical basis for the characterization of Cf-252 sources and will be part of the AK documentation required for submittal to the Central Characterization Project (CCP) of WIPP.« less

  20. Polymer nanocomposites for sealing microannulus cracks in wellbores cement-steel interface

    NASA Astrophysics Data System (ADS)

    Genedy, M.; Fernandez, S. G.; Stormont, J.; Matteo, E. N.; Dewers, T. A.; Reda Taha, M.

    2017-12-01

    Seal integrity of production and storage wellbores has become a critical challenge with the increasing oil and gas leakage incidents. The general consensus is that one of the potential leakage pathways is micro-annuli at the cement-steel interface. In this paper, we examine the efficiency of proposed polymer nanocomposite to seal microannulus cracks at the cement-steel interface. The repair material efficiency is defined as the ability of the repair material to reduce or eliminate the gas permeability of the cement-steel interface. The flow rate of an inert gas (Nitrogen) at the cement-steel interface was investigated for three cases: 1) repaired test samples with traditional repair material (microfine cement), 2) polymer nanocomposites, and 3) unrepaired test samples. Flow rates were measured and compared for all three cases. The experimental results show up to 99.5% seal efficiency achieved by using polymer nanocomposites compared to 20% efficiency achieved in the case of microfine cement. Sandia National Laboratories is a multimission laboratory managed and operated by National Technology and Engineering Solutions of Sandia, LLC., a wholly owned subsidiary of Honeywell International, Inc., for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-NA-0003525. SAND2017-8094 A.

  1. Quick-sealing design for radiological containment

    DOEpatents

    Rampolia, Donald S.; Speer, Elmer

    1990-01-01

    A quick-sealing assembly and method for forming an adhesive seal on opposite sides of a mechanical seal for a flexible containment bag of the type used for working with radioactively contaminated objects. The assembly includes an elongated mechanical fastener having opposing engaging members affixed at a predetermined distance from each of the elongated edges, with an adhesive layer formed between the mechanical fastener and the elongated edge such that upon engagement of the mechanical fastener and adhesive layers to opposing containment fabric, a neat triple hermetic seal is formed.

  2. Quick-sealing design for radiological containment

    DOEpatents

    Rampolla, Donald S.; Speer, Elmer

    1991-01-01

    A quick-sealing assembly and method for forming an adhesive seal on opposite sides of a mechanical seal for a flexible containment bag of the type used for working with radioactively contaminated objects. The assembly includes an elongated mechanical fastener having opposing engaging members affixed at a predetermined distance from each of the elongated edges, with an adhesive layer formed between the mechanical fastener and the elongated edge such that upon engagement of the mechanical fastener and adhesive layers to opposing containment fabric, a neat triple hermetic seal is formed.

  3. Continued Investigation of Leakage and Power Loss Test Results for Competing Turbine Engine Seals

    DTIC Science & Technology

    2006-09-01

    Pressure-balanced design Figure 3.—Annular seal made of Inconel 625 . Note, each grid square is 6.35 mm. Figure 4.—Four-knife labyrinth...seal made of Inconel 625 . NASA/TM—2006-214420 7 Figure 5.—Brush seal with flow deflector. Figure 6.—Finger seal design. NASA/TM—2006-214420 8...thermocouples are located at the 90° and 180° positions (0° is top-dead-center). Type-K thermocouples are used and all are 157 µm, Inconel sheath, closed

  4. Pore-Lining Composition and Capillary Breakthrough Pressure of Mudstone Caprocks: Sealing Efficiency of Geologic CO2 Storage Sites

    NASA Astrophysics Data System (ADS)

    Heath, J. E.; Dewers, T. A.; McPherson, B. J.; Kotula, P. G.

    2010-12-01

    Subsurface containment of CO2 is predicated on effective caprock sealing. Many previous studies have relied on macroscopic measurements of capillary breakthrough pressure and other petrophysical properties without direct examination of solid phases that line pore networks and directly contact fluids. However, pore-lining phases strongly contribute to sealing behavior through interfacial interactions among CO2, brine, and the mineral or non-mineral phases. Our high resolution (i.e., sub-micron) examination of the composition of pore-lining phases of several continental and marine mudstones indicates that sealing efficiency (i.e., breakthrough pressure) is governed by pore shapes and pore-lining phases that are not identifiable except through direct characterization of pores. Bulk X-ray diffraction data does not indicate which phases line the pores and may be especially lacking for mudstones with organic material. Organics can line pores and may represent once-mobile phases that modify the wettability of an originally clay-lined pore network. For shallow formations (i.e., < ~800 m depth), interfacial tension and contact angles result in breakthrough pressures that may be as high as those needed to fracture the rock—thus, in the absence of fractures, capillary sealing efficiency is indicated. Deeper seals have poorer capillary sealing if mica-like wetting dominates the wettability. We thank the U.S. Department of Energy’s National Energy Technology Laboratory and the Office of Basic Energy Sciences, and the Southeast and Southwest Carbon Sequestration Partnerships for supporting this work. Sandia National Laboratories is a multi-program laboratory operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Company, for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-AC04-94AL85000.

  5. Ceramic tube seals cut heat loss, achieve six month payback

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

    Not Available

    1985-11-01

    The methane reformer at the Celanese Chemical Company's Bishop, TX plant operates at approximately 1900/sup 0/F. The reformer has 32 tubes (9'' diameter) that pass through the firebox. Openings around the tubes measure 11'' in diameter to accommodate horizontal and vertical thermal expansion and movement as well as to facilitate tube removal. The gaps around the tubes permitted cool air to be drawn into the firebox (caused by slight negative pressure) and also allowed radiant heat to escape causing the reformer to operate at a lower than desired level of thermal efficiency. Celanese contracted to retrofit the old rigid firebrickmore » roof in the methane reformer with a 10'' thick ceramic fiber module lining. The gaps around the tubes were sealed by using a special tube seal made from Nextel woven ceramic fiber fabric, a 1984 CHEMICAL PROCESSING Vaaler Award winner (Mid-November 1984, p.52). The Nextel fabric used in this application is a heat resistant textile that has a continuous use temperature of 2200/sup 0/F - well above the 1900/sup 0/F operating temperature of the reformer. The tube seals have been working exactly as intended, verified by observation through inspection ports. Temperatures in the penthouse area above the roof dropped from 240/sup 0/F to 150/sup 0/F. The reduction in heat losses has been attributed to the elimination of the gaps around each tube by the seals and to the improved K-factor of the ceramic module lining. The tube seals have paid for themselves within six months of installation. At that time, the seal boots were inspected and showed no signs of wear. With these results, the improved efficiency of the methane reformer promises to yield additional economic benefits.« less

  6. Skew And Twist Resistant Hydrodynamic Rotary Shaft Seal

    DOEpatents

    Dietle, Lannie; Kalsi, Manmohan Singh

    2000-03-14

    A hydrodynamically lubricated squeeze packing type rotary shaft seal suitable for lubricant retention and environmental exclusion which incorporates one or more resilient protuberances which and cooperate with the gland walls to hold the seal straight in its installation groove in unpressurized and low pressure lubricant retention applications thereby preventing skew-induced wear caused by impingement of abrasive contaminants present in the environment, and which also serve as radial bearings to prevent tipping of the seal within its installation gland. Compared to prior art, this invention provides a dramatic reduction of seal and shaft wear in abrasive environments and provides a significant increase in seal life.

  7. Transmission seal development

    NASA Technical Reports Server (NTRS)

    Brien, M.

    1977-01-01

    An experimental evaluation was performed on a high-speed (72.9 m/s, 14,349 ft/min) transmission seal of the synergistic type. During testing of the seal, oil leakage occurred at positive bearing cavity pressures. Modifications were made in an attempt to eliminate the leakage but none were completely successful. Leakage appears to be the result of questionable positioning of the sealing elements resulting in inadequate shaft contact by the oil side sealing element. This condition may be related to the nonsymmetrical shape of the elastomeric retainer and to dimensional changes caused by swelling of the elastomeric retainer from exposure to the sealed fluid. Indications of a speed dependent leakage characteristic were also observed.

  8. Turbomachinery Laboratory Texas A and M University research progress on annular gas seals

    NASA Technical Reports Server (NTRS)

    Childs, Dara W.

    1994-01-01

    Three helically-grooved seals were tested and the results were compared to the MTI code SPIRALG. A smooth annular seal was tested at six eccentricity ratios from 0 to 0.5. The following are concluded in this viewgraph presentation: (1) Helical-grooved seals provide a substantial reduction in cross-coupled stiffness coefficients. Negative k(sub xy) values are obtained for no-swirl or low-swirl cases. (2) SPIRALG is completely unsuitable for the type of seal tested, namely, turbulent flow, wide grooves and lands, etc. (3) A good analysis code is needed to guide the design of helically-grooved annular seals including groove and smooth sections.

  9. Mainshaft seals for small gas turbine engines

    NASA Technical Reports Server (NTRS)

    Ludwig, L. P.; Lynwander, P.

    1974-01-01

    An experimental evaluation of mainshaft seals for small gas turbine engines was conducted with shaft speeds to 213 m/s (700 ft/sec), air pressures to 148 Newtons per square centimeter abs. (215 psia), and air temperatures to 412k(282 F). A radial face seal incorporating self-acting geometry for lift augmentation was evaluated. In addition, three conventional carbon seal types (face, circumferential segmented, and rotating ring) were run for comparison. Test results indicated that the conventional seals used in this evaluation may not be satisfactory in future advanced engines because of excessive air leakage. On the other hand, the self-acting face seal was shown to have the potential capability of limiting leakages to one-half that of the conventional face seals and one-fifth that of conventional ring seals. A 150-hour endurance test of the self-acting face seal was conducted.

  10. 41 CFR 101-45.002 - Gold.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 41 Public Contracts and Property Management 2 2014-07-01 2012-07-01 true Gold. 101-45.002 Section... PERSONAL PROPERTY § 101-45.002 Gold. (a) Gold will be sold in accordance with this section and part 102-38 of the Federal Management Regulation. (b) Sales of gold shall be processed to— (1) Use the sealed bid...

  11. 41 CFR 101-45.002 - Gold.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 41 Public Contracts and Property Management 2 2012-07-01 2012-07-01 false Gold. 101-45.002 Section... PERSONAL PROPERTY § 101-45.002 Gold. (a) Gold will be sold in accordance with this section and part 102-38 of the Federal Management Regulation. (b) Sales of gold shall be processed to— (1) Use the sealed bid...

  12. 41 CFR 101-45.002 - Gold.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 41 Public Contracts and Property Management 2 2011-07-01 2007-07-01 true Gold. 101-45.002 Section... PERSONAL PROPERTY § 101-45.002 Gold. (a) Gold will be sold in accordance with this section and part 102-38 of the Federal Management Regulation. (b) Sales of gold shall be processed to— (1) Use the sealed bid...

  13. 41 CFR 101-45.002 - Gold.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 41 Public Contracts and Property Management 2 2013-07-01 2012-07-01 true Gold. 101-45.002 Section... PERSONAL PROPERTY § 101-45.002 Gold. (a) Gold will be sold in accordance with this section and part 102-38 of the Federal Management Regulation. (b) Sales of gold shall be processed to— (1) Use the sealed bid...

  14. 41 CFR 101-45.002 - Gold.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 41 Public Contracts and Property Management 2 2010-07-01 2010-07-01 true Gold. 101-45.002 Section... PERSONAL PROPERTY § 101-45.002 Gold. (a) Gold will be sold in accordance with this section and part 102-38 of the Federal Management Regulation. (b) Sales of gold shall be processed to— (1) Use the sealed bid...

  15. 48 CFR 52.214-27 - Price Reduction for Defective Certified Cost or Pricing Data-Modifications-Sealed Bidding.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... reduction. This right to a price reduction is limited to that resulting from defects in data relating to... 48 Federal Acquisition Regulations System 2 2010-10-01 2010-10-01 false Price Reduction for... PROVISIONS AND CONTRACT CLAUSES Text of Provisions and Clauses 52.214-27 Price Reduction for Defective...

  16. 48 CFR 928.101-1 - Policy on use.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Policy on use. 928.101-1... REQUIREMENTS BONDS AND INSURANCE Bonds and Other Financial Protections 928.101-1 Policy on use. In addition to... for fixed price or unit price contracts entered into as a result of sealed bidding. They may not be...

  17. Experimental and numerical determination of the static critical pressure in ferrofluid seals

    NASA Astrophysics Data System (ADS)

    Horak, W.; Szczęch, M.

    2013-02-01

    Ferrofluids have various engineering applications; one of them are magnetic fluid seals for rotating shafts. There are various constructions of this type of seals, but the main difference is the number of sealing stages. The development of this construction is a complex process which requires knowledge of ferrofluid physical and rheological properties and the magnetic field distribution inside the sealing gap. One of the most important parameters of ferrofluid seals is the critical (burst) pressure. It is the pressure value at which a leak will occur. This study presents results of numerical simulation of magnetic field distribution inside the seal gap and calculations of the critical pressure value. The obtained pressure values were verified by experiments.

  18. Nozzle seal

    DOEpatents

    Groff, Russell Dennis; Vatovec, Richard John

    1978-06-11

    In an illustrative embodiment of the invention, a nuclear reactor pressure vessel, having an internal hoop from which the heated coolant emerges from the reactor core and passes through to the reactor outlet nozzles, is provided with annular sealing members operatively disposed between the outlet nozzle and the hoop and partly within a retaining annulus formed in the hoop. The sealing members are biased against the pressure vessel and the hoop and one of the sealing members is provided with a piston type pressure ring sealing member which effectively closes the path between the inlet and outlet coolants in the region about the outlet nozzle establishing a leak-proof condition. Furthermore, the flexible responsiveness of the seal assures that the seal will not structurally couple the hoop to the pressure vessel.

  19. Surveillance for zoonotic and selected pathogens in harbor seals Phoca vitulina from central California

    USGS Publications Warehouse

    Greig, Denise J.; Ip, Hon S.; Gulland, Frances M. D.; Miller, Woutrina A.; Conrad, Patricia A.; Field, Cara L.; Fleetwood, Michelle; Harvey, James T.; Jang, Spencer; Packham, Andrea; Wheeler, Elizabeth; Hall, Ailsa J.

    2014-01-01

    The infection status of harbor seals Phoca vitulina in central California, USA, was evaluated through broad surveillance for pathogens in stranded and wild-caught animals from 2001 to 2008, with most samples collected in 2007 and 2008. Stranded animals from Mendocino County to San Luis Obispo County were sampled at a rehabilitation facility: The Marine Mammal Center (TMMC, n = 175); wild-caught animals were sampled at 2 locations: San Francisco Bay (SF, n = 78) and Tomales Bay (TB, n = 97), that differed in degree of urbanization. Low prevalences of Salmonella, Campylobacter, Giardia, and Cryptosporidium were detected in the feces of stranded and wild-caught seals. Clostridium perfringens and Escherichia coli were more prevalent in the feces of stranded (58% [78 out of 135] and 76% [102 out of 135]) than wild-caught (42% [45 out of 106] and 66% [68 out of 106]) seals, whereas Vibrio spp. were 16 times more likely to be cultured from the feces of seals from SF than TB or TMMC (p < 0.005). Brucella DNA was detected in 3.4% of dead stranded harbor seals (2 out of 58). Type A influenza was isolated from feces of 1 out of 96 wild-caught seals. Exposure to Toxoplasma gondii, Sarcocystis neurona, and type A influenza was only detected in the wild-caught harbor seals (post-weaning age classes), whereas antibody titers to Leptospira spp. were detected in stranded and wild-caught seals. No stranded (n = 109) or wild-caught (n = 217) harbor seals had antibodies to phocine distemper virus, although a single low titer to canine distemper virus was detected. These results highlight the role of harbor seals as sentinel species for zoonotic and terrestrial pathogens in the marine environment.

  20. Some developments on ceramic-to-metal and glass-ceramics-to-metal seals and related studies

    NASA Astrophysics Data System (ADS)

    Kothiyal, G. P.; Goswami, M.; Shrikhande, V. K.

    2008-05-01

    Seals and coatings based on ceramics and glass-ceramics find numerous applications in different disciplines of science and technology including space, accelerators, nuclear energy, chemical industry. Ceramic-to-metal (CM) seals based on conventional design (using brazing alloys) and glass-ceramics have been prepared. While Ag-Cu brazing alloy has been used in conventional CM seal, we have employed lithium zinc silicate (LZS) and lithium aluminum silicate (LAS) glass-ceramics for glass-ceramics-to-metal (GCM) seals. LZS glass-ceramics based on two different compositions; (a) LZSL composition (wt.%)- Li2O: 12.65, ZnO: 1.85, SiO2: 74.4, Al2O3: 3.8, K2O: 2.95, P2O5: 3.15, and B2O3: 1.2 (low ZnO) and (b) LZSH composition (wt.%)- Li2O: 8.9, ZnO: 24.03, SiO2: 53.7, Na2O: 5.42, P2O5: 2.95, and B2O3: 5.0 (high ZnO) were prepared with desired sealing characteristics for matched type seals. In addition, (wt.%) 12.6Li2O-71.7SiO2-5.1Al2O3-4.9K2O-3.2B2O3-2.5P2O5 (LAS-GC) was investigated for compressive type of seal. LZS glass-ceramics-to-Cu as well as SS-321 seals were found to withstand a vacuum of 10-6 Torr with leak rate 10-9 Torr. 1/s and LAS GC-to-SS304 seal showed high pressure endurance of 12000psi. In order to understand the mechanism of sealing, glass-ceramics-to-metal interface study has also been carried out.

  1. A NaI(Tl) 241Am light pulser of increased reliability by eliminating epoxy sealing

    NASA Astrophysics Data System (ADS)

    Kobayashi, Masaaki; Takano, Shuichi; Matsumoto, Yoshikazu

    1984-07-01

    A new type of NaI(Tl) 241Am light pulser has been developed without any epoxy sealing so as to improve the reliability significantly. Glass-metal fusing and metal-to-metal welding are employed to seal the NaI(Tl) crystals against moisture.

  2. Inflatable O-ring seal would ease closing of hatch cover plate

    NASA Technical Reports Server (NTRS)

    Neary, K. J.

    1966-01-01

    Inflatable O-ring seal provides positive sealing means that does not require the manual exertion of a large compressive force during opening or closing of a rotary-type hatch cover plate. The O-ring is deflated during opening and closing and inflated after closure by a gas pressure source.

  3. Advanced Seal Development for Large Industrial Gas Turbines

    NASA Technical Reports Server (NTRS)

    Chupp, Raymond E.

    2006-01-01

    Efforts are in progress to develop advanced sealing for large utility industrial gas turbine engines (combustion turbines). Such seals have been under developed for some time for aero gas turbines. It is desired to transition this technology to combustion turbines. Brush seals, film riding face and circumferential seals, and other dynamic and static sealing approaches are being incorporated into gas turbines for aero applications by several engine manufacturers. These seals replace labyrinth or other seals with significantly reduced leakage rates. For utility industrial gas turbines, leakage reduction with advanced sealing can be even greater with the enormous size of the components. Challenges to transitioning technology include: extremely long operating times between overhauls; infrequent but large radial and axial excursions; difficulty in coating larger components; and maintenance, installation, and durability requirements. Advanced sealing is part of the Advanced Turbine Systems (ATS) engine development being done under a cooperative agreement between Westinghouse and the US Department of Energy, Office of Fossil Energy. Seal development focuses on various types of seals in the 501ATS engine both at dynamic and static locations. Each development includes rig testing of candidate designs and subsequent engine validation testing of prototype seals. This presentation gives an update of the ongoing ATS sealing efforts with special emphasis on brush seals.

  4. Hinge Moments of Sealed-Internal-Balance Arrangements for Control Surfaces I : Theoretical Investigation

    NASA Technical Reports Server (NTRS)

    Murray, Harry E.; Erwin, Mary A.

    1945-01-01

    The results of a theoretical analysis of the hinge-moment characteristics of various sealed-internal-balance arrangements for control surfaces are presented. The analysis considered overhands sealed to various types of wing structure by flexible seals spanning gaps of various widths or sealed to the wing structure by a flexible system of linked plates. Leakage was not considered; the seal was assumed to extend the full spanwise length of the control surface. The effect of the developed width of the flexible seal and of the geometry of the structure to which the seal was anchored was investigated, as well as the effect of the gap width that is sealed. The results of the investigation indicated that the most nearly linear control-surface hinge-moment characteristics can probably be obtained from a flexible seal over a narrow gap (about 0.1 of the overhang chord), which is so installed that the motion of the seal is restricted to a region behind the point of attachment of the seal to the wing structure. Control-surface hinge moments that tend to be high at large deflections and low or overbalanced at small deflections will result if a very narrow seal is used.

  5. Seal Investigations of an Active Clearance Control System Concept

    NASA Technical Reports Server (NTRS)

    Steinetz, Bruce M.; Taylor, Shawn; Oswald, Jay; DeCastro, Jonathan A.

    2006-01-01

    In an effort to improve upon current thermal active clearance control methods, a first generation, fast-acting mechanically actuated, active clearance control system has been designed and installed into a non-rotating test rig. In order to harvest the benefit of tighter blade tip clearances, low-leakage seals are required for the actuated carrier segments of the seal shroud to prevent excessive leakage of compressor discharge (P3) cooling air. The test rig was designed and fabricated to facilitate the evaluation of these types of seals, identify seal leakage sources, and test other active clearance control system concepts. The objective of this paper is to present both experimental and analytical investigations into the nature of the face-seal to seal-carrier interface. Finite element analyses were used to examine face seal contact pressures and edge-loading under multiple loading conditions, varied E-seal positions and two new face seal heights. The analyses indicated that moving the E-seal inward radially and reducing face seal height would lead to more uniform contact conditions between the face seal and the carriers. Lab testing confirmed that moving the balance diameter inward radially caused a decrease in overall system leakage.

  6. Hydrodynamically Lubricated Rotary Shaft Having Twist Resistant Geometry

    DOEpatents

    Dietle, Lannie; Gobeli, Jeffrey D.

    1993-07-27

    A hydrodynamically lubricated squeeze packing type rotary shaft with a cross-sectional geometry suitable for pressurized lubricant retention is provided which, in the preferred embodiment, incorporates a protuberant static sealing interface that, compared to prior art, dramatically improves the exclusionary action of the dynamic sealing interface in low pressure and unpressurized applications by achieving symmetrical deformation of the seal at the static and dynamic sealing interfaces. In abrasive environments, the improved exclusionary action results in a dramatic reduction of seal and shaft wear, compared to prior art, and provides a significant increase in seal life. The invention also increases seal life by making higher levels of initial compression possible, compared to prior art, without compromising hydrodynamic lubrication; this added compression makes the seal more tolerant of compression set, abrasive wear, mechanical misalignment, dynamic runout, and manufacturing tolerances, and also makes hydrodynamic seals with smaller cross-sections more practical. In alternate embodiments, the benefits enumerated above are achieved by cooperative configurations of the seal and the gland which achieve symmetrical deformation of the seal at the static and dynamic sealing interfaces. The seal may also be configured such that predetermined radial compression deforms it to a desired operative configuration, even through symmetrical deformation is lacking.

  7. Skew and twist resistant hydrodynamic rotary shaft seal

    DOEpatents

    Dietle, Lannie; Kalsi, Manmohan Singh

    1999-01-01

    A hydrodynamically lubricated squeeze packing type rotary shaft seal suitable for lubricant retention and environmental exclusion which incorporates one or more resilient protuberances which and cooperate with the gland walls to hold the seal straight in its installation groove in unpressurized and low pressure lubricant retention applications thereby preventing skew-induced wear caused by impingement of abrasive contaminants present in the environment, and which also serve as radial bearings to prevent tipping of the seal within its installation gland.

  8. Advanced Compressor for Long Life Space Cryocoolers

    DTIC Science & Technology

    1994-11-01

    demonstrate the advantages ( high reliability, low weight, and long life) of hermetically sealed diaphragm-type compressors intended for space...Allowable Design Stresses Under High -Cycle Fatigue Conditions............................... ........... 91 B: PHILLIPS.TDS Cryocooler Compressor...of the overall program was to demonstrate the advantages ( high reliability, low weight, and long life)’of hermetically sealed diaphragm-type

  9. Program for the improvement of downhole drilling motor bearings and seals. Phase IV. Semi-annual report

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

    Tibbitts, G.A.; DeLafosse, P.H.; Black, A.

    1980-07-01

    Four main areas of development for the project are covered: design and fabrication of a dynamometer and a mud cooling system for the Bearing-Seal Package Test Facility; modification of the Bearing-Seal Package Test Facility based on test results; testing of new lubricant samples from Pacer Lubricants, Inc., in the Terra Tek High Temperature Lubricant Tester; and testing of new seal types in the Terra Tek Sea Tester. The Maurer Engineering Report, Semi-Annual Progress Report on Improvement of Downhole Motor Bearings and Seals by Jeff L. Barnwell, has been included as Appendix B.

  10. Evaluation of mine seals constructed in 1967 at Elkins, Randolph County, West Virginia. Report of investigations/1984

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

    Adams, L.M.; Lipscomb, J.R.

    1984-01-01

    In 1980, the Bureau of Mines surveyed a group of mine seals in Randolph County, WV, to evaluate their effectiveness for reducing toxic pollutants in mine water discharges. The survey focused on 11 block wet mine seals, but mine seals of several other types were also examined. The seals were designed to prevent air from entering the mine portals while allowing mine water to flow out. It was believed that by preventing air from entering inactive or abandoned mines, the formation of toxic pollutants and acid mine drainage (AMD) could be reduced.

  11. Cone beam tomographic study of facial structures characteristics at rest and wide smile, and their correlation with the facial types.

    PubMed

    Martins, Luciana Flaquer; Vigorito, Julio Wilson

    2013-01-01

    To determine the characteristics of facial soft tissues at rest and wide smile, and their possible relation to the facial type. We analyzed a sample of forty-eight young female adults, aged between 19.10 and 40 years old, with a mean age of 30.9 years, who had balanced profile and passive lip seal. Cone beam computed tomographies were performed at rest and wide smile postures on the entire sample which was divided into three groups according to individual facial types. Soft tissue features analysis of the lips, nose, zygoma and chin were done in sagittal, axial and frontal axis tomographic views. No differences were observed in any of the facial type variables for the static analysis of facial structures at both rest and wide smile postures. Dynamic analysis showed that brachifacial types are more sensitive to movement, presenting greater sagittal lip contraction. However, the lip movement produced by this type of face results in a narrow smile, with smaller tooth exposure area when compared with other facial types. Findings pointed out that the position of the upper lip should be ahead of the lower lip, and the latter, ahead of the pogonion. It was also found that the facial type does not impact the positioning of these structures. Additionally, the use of cone beam computed tomography may be a valuable method to study craniofacial features.

  12. Rotordynamic Behavior Of Sawtooth-Pattern Damping Seals

    NASA Technical Reports Server (NTRS)

    Nolan, Steven A.

    1992-01-01

    Report describes comparative experimental and theoretical study of rotordynamics of several different annular liquid pump seals. Introduces damping seals of new type in which inner surfaces of stators have saw-tooth-cross-section axial grooves interrupted at regular axial intervals by circumferential dams. Teeth of sawtooth patterns directed against rotations in attempt to reduce further asymptotic circumferential velocities of fluids.

  13. 40 CFR 63.3168 - What are the requirements for continuous parameter monitoring system installation, operation, and...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... the atmosphere. (ii) Car-seal or lock-and-key valve closures. Secure any bypass line valve in the closed position with a car-seal or a lock-and-key type configuration. You must visually inspect the seal... sensor. (vii) At least monthly, inspect components for integrity and electrical connections for...

  14. 40 CFR 63.3168 - What are the requirements for continuous parameter monitoring system installation, operation, and...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... the atmosphere. (ii) Car-seal or lock-and-key valve closures. Secure any bypass line valve in the closed position with a car-seal or a lock-and-key type configuration. You must visually inspect the seal... sensor. (vii) At least monthly, inspect components for integrity and electrical connections for...

  15. Laser stapedotomy: a comparative study of prostheses and seals.

    PubMed

    Perkins, R; Curto, F S

    1992-12-01

    During the past 13 years, a number of prostheses of differing design and tissue seals have been used in laser stapedotomy for otosclerosis. This study compares the results of three different configurations of prostheses and tissue seals in a series of 53 patients. In 19, a platinum wire Teflon piston was placed in the laser stapedotomy fenestra and crimped on the long process of the incus; autologous venous blood was infiltrated into the oval window niche as a sealing mechanism. In 8 patients, a stainless steel bucket-handle-type prosthesis was used with a blood tissue seal. In 26 patients, a segment of autogenous vein was clad onto the bucket-handle-type prosthesis and placed into the laser fenestra. Two tissue seals (blood and vein) were also compared. The results were compared with regard to several audiometric parameters. It would appear that the bucket handle/vein configuration improves air-bone gap closure in the low- and mid-frequency speech range and also shows an advantage for air-bone gap closure to 10 dB or less compared to the other configurations in this study. Mean postoperative gaps were significantly less for vein compared to the blood tissue seal. Physiologic and surgical implications are discussed, and the vein-clad technique is illustrated.

  16. 75 FR 54560 - Federal Acquisition Regulation; Clarification of Standard Form 26-Award/Contract

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-08

    ... changes will not prohibit the use of the SF 26 for awarding negotiated procurements; it will only prohibit... Budget under 44 U.S.C. chapter 35, et seq. List of Subjects in 48 CFR Part 53 Government procurement... be used when awarding a negotiated procurement and should only be checked when awarding a sealed-bid...

  17. Skew and twist resistant hydrodynamic rotary shaft seal

    DOEpatents

    Dietle, L.; Kalsi, M.S.

    1999-02-23

    A hydrodynamically lubricated squeeze packing type rotary shaft seal suitable for lubricant retention and environmental exclusion which incorporates one or more resilient protuberances which cooperate with the gland walls to hold the seal straight in its installation groove in unpressurized and low pressure lubricant retention applications thereby preventing skew-induced wear caused by impingement of abrasive contaminants present in the environment, and which also serve as radial bearings to prevent tipping of the seal within its installation gland. 14 figs.

  18. Development of hypersonic engine seals: Flow effects of preload and engine pressures

    NASA Technical Reports Server (NTRS)

    Cai, Zhong; Mutharasan, Rajakkannu; Ko, Frank K.; Steinetz, Bruce M.

    1993-01-01

    A new type of engine seal is being developed to meet the needs of advanced hypersonic engines. A seal braided of emerging high temperature ceramic fibers comprised of a sheath-core construction was selected for study based on its low leakage rates. Flexible, low-leakage, high temperature seals are required to seal the movable engine panels of advanced ramjet-scramjet engines either preventing potentially dangerous leakage into backside engine cavities or limiting the purge coolant flow rates through the seals. To predict the leakage through these flexible, porous seal structures as a function of preload and engine pressures, new analytical flow models are required. An empirical leakage resistance/preload model is proposed to characterize the observed decrease in leakage with increasing preload. Empirically determined compression modulus and preload factor are used to correlate experimental leakage data for a wide range of seal architectures. Good agreement between measured and predicted values are observed over a range of engine pressures and seal preloads.

  19. An Overview of Advanced Elastomeric Seal Development and Testing Capabilities at NASA Glenn Research Center

    NASA Technical Reports Server (NTRS)

    Dunlap, Patrick H., Jr.

    2014-01-01

    NASA is developing advanced space-rated elastomeric seals to support future space exploration missions to low Earth orbit, the Moon, near Earth asteroids, and other destinations. This includes seals for a new docking system and vehicle hatches. These seals must exhibit extremely low leak rates to ensure that astronauts have sufficient breathable air for extended missions. Seal compression loads must be below prescribed limits so as not to overload the mechanisms that compress them, and seal adhesion forces must be low to allow the sealed interface to be separated when required (e.g., during undocking or hatch opening). NASA Glenn Research Center has developed a number of unique test fixtures to measure the leak rates and compression and adhesion loads of candidate seal designs under simulated thermal, vacuum, and engagement conditions. Tests can be performed on fullscale seals with diameters on the order of 50 in., subscale seals that are about 12 in. in diameter, and smaller specimens such as O-rings. Test conditions include temperatures ranging from -238 to 662degF (-150 to 350degC), operational pressure gradients, and seal-on-seal or seal-on-flange mating configurations. Nominal and off-nominal conditions (e.g., incomplete seal compression) can also be simulated. This paper describes the main design features and capabilities of each type of test apparatus and provides an overview of advanced seal development activities at NASA Glenn.

  20. An Overview of Advanced Elastomeric Seal Development and Testing Capabilities at NASA Glenn Research Center

    NASA Technical Reports Server (NTRS)

    Dunlap, Patrick H.

    2014-01-01

    NASA is developing advanced space-rated elastomeric seals to support future space exploration missions to low Earth orbit, the Moon, near Earth asteroids, and other destinations. This includes seals for a new docking system and vehicle hatches. These seals must exhibit extremely low leak rates to ensure that astronauts have sufficient breathable air for extended missions. Seal compression loads must be below prescribed limits so as not to overload the mechanisms that compress them, and seal adhesion forces must be low to allow the sealed interface to be separated when required (e.g., during undocking or hatch opening). NASA Glenn Research Center has developed a number of unique test fixtures to measure the leak rates and compression and adhesion loads of candidate seal designs under simulated thermal, vacuum, and engagement conditions. Tests can be performed on full-scale seals with diameters on the order of 50 in., subscale seals that are about 12 in. in diameter, and smaller specimens such as O-rings. Test conditions include temperatures ranging from -238 to 662 F (-150 to 350 C), operational pressure gradients, and seal-on-seal or seal-on-flange mating configurations. Nominal and off-nominal conditions (e.g., incomplete seal compression) can also be simulated. This paper describes the main design features and capabilities of each type of test apparatus and provides an overview of advanced seal development activities at NASA Glenn.

  1. Cyclic tests of P-bulb end-seal designs for a shuttle-type wing-elevon cove membrane seal

    NASA Technical Reports Server (NTRS)

    Hunt, L. R.

    1979-01-01

    Four P-bulb end seal designs were tested at room temperature in a cyclic seal test apparatus. Test results show that all the P-bulb end seals have the durability required for a 100 mission life (neglecting possible elevated-temperature effects) and three of the four P-bulbs provide an adequate seal against a 7.0-kPa air pressure differential. Antifriction material attached to the P-bulb rub surface reduced friction slightly but could degrade the sealing effectiveness. A flat rub surface molded into the P-bulb discouraged wrinkling and rolling and thereby reduced leakage. However, the P-bulbs lacked resilience, as indicated by increased leakage when P-bulb compression was reduced. The best P-bulb design tested included an antifriction interface bonded to a flat surface molded into the P-bulb.

  2. Foil Face Seal Testing

    NASA Technical Reports Server (NTRS)

    Munson, John

    2009-01-01

    In the seal literature you can find many attempts by various researchers to adapt film riding seals to the gas turbine engine. None have been successful, potential distortion of the sealing faces is the primary reason. There is a film riding device that does accommodate distortion and is in service in aircraft applications, namely the foil bearing. More specifically a foil thrust bearing. These are not intended to be seals, and they do not accommodate large axial movement between shaft & static structure. By combining the 2 a unique type of face seal has been created. It functions like a normal face seal. The foil thrust bearing replaces the normal primary sealing surface. The compliance of the foil bearing allows the foils to track distortion of the mating seal ring. The foil seal has several perceived advantages over existing hydrodynamic designs, enumerated in the chart. Materials and design methodology needed for this application already exist. Also the load capacity requirements for the foil bearing are low since it only needs to support itself and overcome friction forces at the antirotation keys.

  3. Numerical simulation on reasonable hole-sealing depth of boreholes for gas extraction

    NASA Astrophysics Data System (ADS)

    Zhao, Dan; Pan, Jingtao

    2018-04-01

    To overcome the low efficiency of extracting gas in coal reservoirs with a low gas permeability, some boreholes were drilled for gas extraction in No. 2 coal reservoir of Wangjialing Coalmine in Shanxi Province, China and reasonably sealed. Aiming at shortfalls such as rapid attenuation of volume for extracted gas as well as low gas permeability when using boreholes in the No. 2 coal reservoir, the traditional COMSOL MultiphysicsMT Earth Science Module was used to couple the three governing equations (Darcy-Brinkman-Navier-Stokes) for fluids. On this basis, numerical simulation on the seepage law along the directions of roadways and boreholes was carried out. The simulation results indicated that when the hole-sealing length was within the width range of fractures in roadways, the negative pressure not only led the gas in surrounding rock masses to flow to the boreholes, but also made the air flow in roadways to permeate into coal walls. As a result, gas and air flows both entered into the boreholes through the loosening zone containing fractures, resulting in seepage of air in roadway to the boreholes. The seepage velocity along the roadway direction under condition with a hole-sealing length of 12 m was obviously slower than that when the hole-sealing length was 8 m. While, the method by simply increasing the length of the hole-sealing section for boreholes failed to effectively stop the air flow in roadways from permeating into the coal wall and then entering the boreholes. Moreover, the increase in the hole-sealing length brought about much more difficulties to the hole-sealing construction. So, the method is not operable in practical condition of the coal mine. Therefore, it is necessary to improve the traditional hole-sealing technology based on foamed macromolecular materials which are mainly made of polyurethane (PU) and use the fluid wall-type hole-sealing technology based on solid-liquid coupling. Then, the effects of gas extraction before and after using the fluid wall-type hole-sealing technology based on solid-liquid coupling to increase the hole-sealing length to 12 m were compared. The comparison results revealed that the pure extraction amount of gas from a single borehole in the No. 2 coal reservoir of Wangjialing Coalmine was improved by 4˜6 times. In addition, the concentration of extracted gas increased from less than 1% under the traditional hole-sealing mode to 20%˜25%, with an increase of more than 20 times. The extraction effect of the No. 2 coal reservoir of the coal mine was significantly enhanced by employing the fluid-wall-type hole-sealing technology based on solid-liquid coupling.

  4. Environmental and customer-driven seal requirements

    NASA Technical Reports Server (NTRS)

    Hendricks, Robert C.

    1994-01-01

    Public awareness of environmental hazards, well-publicized effects of hazardous leakages (Three Mile Island, Challenger), and a general concern for planet earth have precipitated emission limits that drive the design requirements for seals applications. Types of seals, barrier fluids, and the necessity of thin lubricating films and stable turbomachine operation to minimize leakage and material losses generated by rubbing contact are discussed.

  5. Environmental and customer-driven seal requirements

    NASA Astrophysics Data System (ADS)

    Hendricks, Robert C.

    1994-07-01

    Public awareness of environmental hazards, well-publicized effects of hazardous leakages (Three Mile Island, Challenger), and a general concern for planet earth have precipitated emission limits that drive the design requirements for seals applications. Types of seals, barrier fluids, and the necessity of thin lubricating films and stable turbomachine operation to minimize leakage and material losses generated by rubbing contact are discussed.

  6. Clypeotheca, a new skeletal structure in scleractinian corals: a potential stress indicator

    NASA Astrophysics Data System (ADS)

    Nothdurft, L. D.; Webb, G. E.

    2009-03-01

    Physiological responses to environmental stress are increasingly well studied in scleractinian corals. This work reports a new stress-related skeletal structure we term clypeotheca. Clypeotheca was observed in several live-collected common reef-building coral genera and a two to three kya subfossil specimen from Heron Reef, Great Barrier Reef and consists of an epitheca-like skeletal wall that seals over the surface of parts of the corallum in areas of stress or damage. It appears to form from a coordinated process wherein neighboring polyps and adjoining coenosarc seal themselves off from the surrounding environment as they contract and die. Clypeotheca forms from inward skeletal centripetal growth at the edges of corallites and by the merging of flange-like outgrowths that surround individual spines over the surface of the coenosteum. Microstructurally, the merged flanges are similar to upside-down dissepiments and true epitheca. Clypeotheca is interpreted primarily as a response to stress that may help protect the colony from invasion of unhealthy tissues by parasites or disease by retracting tissues in areas that have become unhealthy for the polyps. Identification of skeletal responses of corals to environmental stress may enable the frequency of certain types of environmental stress to be documented in past environments. Such data may be important for understanding the nature of reef dynamics through intervals of climate change and for monitoring the effects of possible anthropogenic stress in modern coral reef habitats.

  7. High temperature braided rope seals for static sealing applications

    NASA Technical Reports Server (NTRS)

    Adams, Michael L.; Olsen, Andrew; Darolia, Ram; Steinetz, Bruce M.; Bartolotta, Paul A.

    1996-01-01

    Achieving efficiency and performance goals of advanced aircraft and industrial systems are leading designers to implement high temperature materials such as ceramics and intermetallics. Generally these advanced materials are applied selectively in the highest temperature sections of the engine system including the combustor and high pressure turbine, amongst others. Thermal strains that result in attaching the low expansion-rate components to high expansion rate superalloy structures can cause significant life reduction in the components. Seals are being designed to both seal and to serve as compliant mounts allowing for relative thermal growths between high temperature but brittle primary structures and the surrounding support structures. Designers require high temperature, low-leakage, compliant seals to mitigate thermal stresses and control parasitic and cooling airflow between structures. NASA is developing high temperature braided rope seals in a variety of configurations to help solve these problems. This paper will describe the types of seals being developed, describe unique test techniques used to assess seal performance, and present leakage flow data under representative pressure, temperature and scrubbing conditions. Feasibility of the braided rope seals for both an industrial tube seal and a turbine vane seal application is also demonstrated.

  8. High Temperature Propulsion System Structural Seals for Future Space Launch Vehicles

    NASA Technical Reports Server (NTRS)

    Dunlap, Patrick H., Jr.; Steinetz, Bruce M.; DeMange, Jeffrey J.

    2004-01-01

    Durable, flexible sliding seals are required in advanced hypersonic engines to seal the perimeters of movable engine ramps for efficient, safe operation in high heat flux environments at temperatures of 2000 to 2500 F. Current seal designs do not meet the demanding requirements for future engines, so NASA s Glenn Research Center is developing advanced seals and preloading devices to overcome these shortfalls. An advanced ceramic wafer seal design and two types of seal preloading devices were evaluated in a series of compression, scrub, and flow tests. Silicon nitride wafer seals survived 2000 in. 1000 cycles) of scrubbing at 1600 F against an Inconel 625 rub surface with no chips or signs of damage. Flow rates measured for the wafers before and after scrubbing were almost identical and were up to 32 times lower than those recorded for the best braided rope seal flow blockers. Canted coil springs and silicon nitride compression springs showed promise conceptually as potential seal preloading devices to help maintain seal resiliency. A finite element model of the canted coil spring revealed that it should be possible to produce a spring out of high temperature materials for applications at 2000+ F.

  9. High Temperature Propulsion System Structural Seals for Future Space Launch Vehicles

    NASA Technical Reports Server (NTRS)

    Dunlap, Patrick H., Jr.; Steinetz, Bruce M.; DeMange, Jeffrey J.

    2003-01-01

    Durable, flexible sliding seals are required in advanced hypersonic engines to seal the perimeters of movable engine ramps for efficient, safe operation in high heat flux environments at temperatures of 2000 to 2500 F. Current seal designs do not meet the demanding requirements for future engines, so NASA's Glenn Research Center is developing advanced seals and preloading devices to overcome these shortfalls. An advanced ceramic wafer seal design and two types of seal preloading devices were evaluated in a series of compression, scrub, and flow tests. Silicon nitride wafer seals survived 2000 in. (1000 cycles) of scrubbing at room temperature against an Inconel 625 rub surface with no chips or signs of damage. Flow rates measured for the wafers before and after scrubbing were almost identical and were much lower than those recorded for the best braided rope seal flow blockers. Canted coil springs and silicon nitride compression springs showed promise conceptually as potential seal preloading devices to help maintain seal resiliency. A finite element model of the canted coil spring revealed that it should be possible to produce a spring out of high temperature materials for applications at 2000+ F.

  10. 48 CFR 16.104 - Factors in selecting contract types.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 1 2014-10-01 2014-10-01 false Factors in selecting... CONTRACTING METHODS AND CONTRACT TYPES TYPES OF CONTRACTS Selecting Contract Types 16.104 Factors in selecting contract types. There are many factors that the contracting officer should consider in selecting and...

  11. 48 CFR 16.104 - Factors in selecting contract types.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 1 2013-10-01 2013-10-01 false Factors in selecting... CONTRACTING METHODS AND CONTRACT TYPES TYPES OF CONTRACTS Selecting Contract Types 16.104 Factors in selecting contract types. There are many factors that the contracting officer should consider in selecting and...

  12. 48 CFR 52.214-26 - Audit and Records-Sealed Bidding.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...: Audit and Records—Sealed Bidding (OCT 2010) (a) As used in this clause, records includes books, documents, accounting procedures and practices, and other data, regardless of type and regardless of whether...

  13. Concentrations of polycyclic aromatic hydrocarbons (PAHs) and major and trace elements in simulated rainfall runoff from parking lots, Austin, Texas, 2003

    USGS Publications Warehouse

    Mahler, Barbara J.; Van Metre, Peter C.; Wilson, Jennifer T.

    2004-01-01

    Samples of creek bed sediment collected near seal-coated parking lots in Austin, Texas, by the City of Austin during 2001–02 had unusually elevated concentrations of polycyclic aromatic hydrocarbons (PAHs). To investigate the possibility that PAHs from seal-coated parking lots might be transported to urban creeks, the U.S. Geological Survey, in cooperation with the City of Austin, sampled runoff and scrapings from four test plots and 13 urban parking lots. The surfaces sampled comprise coal-tar-emulsion-sealed, asphalt-emulsion-sealed, unsealed asphalt, and unsealed concrete. Particulates and filtered water in runoff and surface scrapings were analyzed for PAHs. In addition, particulates in runoff were analyzed for major and trace elements. Samples of all three media from coal-tar-sealed parking lots had concentrations of PAHs higher than those from any other types of surface. The mean total PAH concentration in particulates in runoff from parking lots in use were 3,500,000, 620,000, and 54,000 micrograms per kilogram from coal-tar-sealed, asphalt-sealed, and unsealed (asphalt and concrete combined) lots, respectively. The probable effect concentration sediment quality guideline is 22,800 micrograms per kilogram. The mean total PAH (sum of detected PAHs) concentration in filtered water from parking lots in use was 8.6 micrograms per liter for coal-tar-sealed lots; the one sample analyzed from an asphalt-sealed lot had a concentration of 5.1 micrograms per liter and the one sample analyzed from an unsealed asphalt lot was 0.24 microgram per liter. The mean total PAH concentration in scrapings was 23,000,000, 820,000, and 14,000 micrograms per kilogram from coal-tar-sealed, asphalt-sealed, and unsealed asphalt lots, respectively. Concentrations of lead and zinc in particulates in runoff frequently exceeded the probable effect concentrations, but trace element concentrations showed no consistent variation with parking lot surface type.

  14. An Alternative Approach for Treating a Type Ia Endoleak after Conventional EVAR Using the Nellix Endovascular Aneurysm Sealing.

    PubMed

    Martinelli, Ombretta; Fresilli, Mauro; Irace, Luigi; Venosi, Salvatore; Jabbour, Jihad; Picone, Veronica; Maruca, Debora; Di Girolamo, Alessia; Gossetti, Bruno

    2018-05-01

    To report the use of a Nellix endovascular aneurysm sealing (EVAS) device, to successfully treat a type Ia endoleak (EL) after an endovascular aortic repair (EVAR). A 70-year-old man was diagnosed with a 90-mm aortic aneurysm, suspicious for being inflammatory. It was initially treated successfully, with a Medtronic Endurant (Medtronic, Minneapolis, MN, USA). Five years after the index endovascular repair, an asymptomatic type Ia EL was detected on duplex ultrasound and computed tomographic angiogram. Other endovascular solutions in the form of proximal cuff, chimney was considered difficult to execute due to challenges in planning, manipulation, and renal cannulation caused by the short proximal sealing zone above the existing stent graft and the constraints of the previous endograft. Thus, a relining of the previous endoprothesis was performed using the Nellix system (Endologix, Inc., Irvine, CA, USA). One-year follow-up imaging demonstrated successful resolution of the EL and persistent sealing of the Nellix device. Nellix EVAS system can be an alternative and safe option for relining a stent graft with a type Ia EL. Nellix platform can be added to the clinician's armamentarium for treating type Ia EL after conventional EVAR of infrarenal abdominal aortic aneurysm (AAA). Copyright © 2018 Elsevier Inc. All rights reserved.

  15. Development of Advanced Carbon Face Seals for Aircraft Engines

    NASA Astrophysics Data System (ADS)

    Falaleev, S. V.; Bondarchuk, P. V.; Tisarev, A. Yu

    2018-01-01

    Modern aircraft gas turbine engines require the development of seals which can operate for a long time with low leakages. The basic type of seals applied for gas turbine engine rotor supports is face seal. To meet the modern requirements of reliability, leak-tightness and weight, low-leakage gas-static and hydrodynamic seals have to be developed. Dry gas seals use both gas-static and hydrodynamic principles. In dry gas seals microgrooves are often used, which ensure the reverse injection of leakages in the sealed cavity. Authors have developed a calculation technique including the concept of coupled hydrodynamic, thermal and structural calculations. This technique allows to calculate the seal performance taking into account the forces of inertia, rupture of the lubricant layer and the real form of the gap. Authors have compared the efficiency of seals with different forms of microgrooves. Results of calculations show that seal with rectangular form of microgrooves has a little gap leading to both the contact of seal surfaces and the wear. Reversible microgrooves have a higher oil mass flow rate, whereas HST micro-grooves have good performance, but they are difficult to produce. Spiral microgrooves have both an acceptable leakages and a high stiffness of liquid layer that is important in terms of ensuring of sealing performance at vibration conditions. Therefore, the spiral grooves were chosen for the developed seal. Based on calculation results, geometric dimensions were chosen to ensure the reliability of the seal operation by creating a guaranteed liquid film, which eliminates the wear of the sealing surfaces. Seals designed were tested both at the test rig and in the engine.

  16. Fuel cell separator plate with bellows-type sealing flanges

    DOEpatents

    Louis, G.A.

    1984-05-29

    A fuel cell separator includes a rectangular flat plate having two unitary upper sealing flanges respectively comprising opposite marginal edges of the plate folded upwardly and back on themselves and two lower sealing flanges respectively comprising the other two marginal edges of the plate folded downwardly and back on themselves. Each of the sealing flanges includes a flat wall spaced from the plate and substantially parallel thereto and two accordion-pleated side walls, one of which interconnects the flat wall with the plate and the other of which steps just short of the plate, these side walls affording resilient compressibility to the sealing flange in a direction generally normal to the plane of the plate. Four corner members close the ends of the sealing flanges. An additional resiliently compressible reinforcing member may be inserted in the passages formed by each of the sealing flanges with the plate.

  17. Fuel cell separator plate with bellows-type sealing flanges

    DOEpatents

    Louis, George A.

    1986-08-05

    A fuel cell separator includes a rectangular flat plate having two unitary upper sealing flanges respectively comprising opposite marginal edges of the plate folded upwardly and back on themselves and two lower sealing flanges respectively comprising the other two marginal edges of the plate folded downwardly and back on themselves. Each of the sealing flanges includes a flat wall spaced from the plate and substantially parallel thereto and two accordion-pleated side walls, one of which interconnects the flat wall with the plate and the other of which stops just short of the plate, these side walls affording resilient compressibility to the sealing flange in a directiongenerally normal to the plane of the plate. Four corner members close the ends of the sealing flanges. An additional resiliently compressible reinforcing member may be inserted in the passages formed by each of the sealing flanges with the plate.

  18. Blood oxygen depletion is independent of dive function in a deep diving vertebrate, the northern elephant seal.

    PubMed

    Meir, Jessica U; Robinson, Patrick W; Vilchis, L Ignacio; Kooyman, Gerald L; Costa, Daniel P; Ponganis, Paul J

    2013-01-01

    Although energetics is fundamental to animal ecology, traditional methods of determining metabolic rate are neither direct nor instantaneous. Recently, continuous blood oxygen (O2) measurements were used to assess energy expenditure in diving elephant seals (Mirounga angustirostris), demonstrating that an exceptional hypoxemic tolerance and exquisite management of blood O2 stores underlie the extraordinary diving capability of this consummate diver. As the detailed relationship of energy expenditure and dive behavior remains unknown, we integrated behavior, ecology, and physiology to characterize the costs of different types of dives of elephant seals. Elephant seal dive profiles were analyzed and O2 utilization was classified according to dive type (overall function of dive: transit, foraging, food processing/rest). This is the first account linking behavior at this level with in vivo blood O2 measurements in an animal freely diving at sea, allowing us to assess patterns of O2 utilization and energy expenditure between various behaviors and activities in an animal in the wild. In routine dives of elephant seals, the blood O2 store was significantly depleted to a similar range irrespective of dive function, suggesting that all dive types have equal costs in terms of blood O2 depletion. Here, we present the first physiological evidence that all dive types have similarly high blood O2 demands, supporting an energy balance strategy achieved by devoting one major task to a given dive, thereby separating dive functions into distinct dive types. This strategy may optimize O2 store utilization and recovery, consequently maximizing time underwater and allowing these animals to take full advantage of their underwater resources. This approach may be important to optimizing energy expenditure throughout a dive bout or at-sea foraging trip and is well suited to the lifestyle of an elephant seal, which spends > 90% of its time at sea submerged making diving its most "natural" state.

  19. Prime Contract Awards by Service Category and Federal Supply Classification Fiscal Years 1987, 1986, 1985, and 1984.

    DTIC Science & Technology

    1987-01-01

    RECREATIONAL AND GYMNASTIC EQUIPMENT 6.225 2,390 3,790 5,248 TOTAL RECREATIONAL AND ATHLETIC EQUIPMENT 9.749 4,303 6,107 7.703 CLEANING EQUIPMENT AND...PAINTS, SEALERS AND ADHESIVES (CONT) 8020 PAINT AND ARTISTS BRUSHES 186 0 0 0 8030 PRESERVATIVE AND SEALING COMPOUNDS 1,030 780 2,485 1,503 8040

  20. Small Business Innovations (Robotic Wrist)

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Under a Langley Research Center Small Business Innovation Research (SBIR) contract, Ross-Hime Designs, Inc. Minneapolis, MN, developed the Omni-Wrist actuator, which has a 25-pound capacity, 180 degrees of pitch/yaw, and 360 degrees of roll. Company literature calls it "the first successful singularity-free high-precision (robotic) wrist." Applications include spray painting, sealing, ultrasonic testing, welding and a variety of nuclear industry, aerospace and military uses.

  1. Space shuttle seal material and design development for earth storable propellant systems

    NASA Technical Reports Server (NTRS)

    1973-01-01

    The results of a program to investigate and characterize seal materials suitable for space shuttle storable propellant systems are given. Two new elastomeric materials were identified as being potentially superior to existing state-of-the art materials for specific sealing applications. These materials were AF-E-124D and AF-E-411. AF-E-124D is a cured perfluorinated polymer suitable for use with dinitrogen tetroxide oxidizer, and hydrazine base fuels. AF-E-411 is an ethylene propylene terpolymer material for hydrazine base fuel service. Data are presented relative to low and high temperature characteristics as well as propellant exposure effects. Types of data included are: mechanical properties, stress strain curves, friction and wear characteristics, compression set and permeability. Sealing tests with a flat poppet-seal valve were conducted for verification of sealing capability. A bibliography includes over 200 references relating to seal design or materials and presents a concise tabulation of the more useful seal design data sources.

  2. High-temperature seals and lubricants for geothermal rock bits. Final report

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

    Hendrickson, R.R.; Winzenried, R.W.; Jones A.H.

    1981-04-01

    High temperature seals (elastomeric and mechanical) and lubricants were developed specifically for journal-type rock bits to be used in geothermal well drilling. Results at simulated downhole conditions indicate that five selected elastomeric seals (L'Garde No. 267, Utex Nos. 227, 231 and HTCR, and Sandia Glow Discharge Coated Viton) are capable of 288/sup 0/C (500/sup 0/F) service. Two prototype mechanical seals did not achieve the life determined for the elastomeric seals. Six lubricants (Pacer PLX-024 oil, PLX-043 oil, PLX-045 oil, Geobond Oil, and Geobond Grease) demonstrated 316/sup 0/C (600/sup 0/F) capability. Recommendation is made for full-scale simulated geothermal drilling tests utilizingmore » the improved elastomeric seals and lubricants.« less

  3. A comparison of experimental and theoretical results for leakage, pressure distribution, and rotordynamic coefficients for annular gas seals

    NASA Technical Reports Server (NTRS)

    Nicks, C. O.; Childs, D. W.

    1984-01-01

    The importance of seal behavior in rotordynamics is discussed and current annular seal theory is reviewed. A Nelson's analytical-computational method for determining rotordynamic coefficients for this type of compressible-flow seal is outlined. Various means for the experimental identification of the dynamic coefficients are given, and the method employed at the Texas A and M University (TAMU) test facility is explained. The TAMU test apparatus is described, and the test procedures are discussed. Experimental results, including leakage, entrance-loss coefficients, pressure distributions, and rotordynamic coefficients for a smooth and a honeycomb constant-clearance seal are presented and compared to theoretical results from Nelson's analysis. The results for both seals show little sensitivity to the running speed over the test range. Agreement between test results and theory for leakage through the seal is satisfactory. Test results for direct stiffness show a greater sensitivity to fluid pre-rotation than predicted. Results also indicate that the deliberately roughened surface of the honeycomb seal provides improved stability versus the smooth seal.

  4. Seal ring installation tool

    NASA Technical Reports Server (NTRS)

    Haselmaier, L. Haynes (Inventor)

    2004-01-01

    A seal ring tool that allows an installer to position a primary seal ring between hub ends of pipe flanges that are being assembled together. The tool includes a pivoting handle member and extension arms attached to the pivoting handle member. The ends of the arms have side indentation type longitudinal grooves angled toward one another for holding the primary seal ring in place between the hubs of respective pipes that are to be attached together. The arms of the tool can also have flat sides that can be used to abut against an optional second larger seal that is supported within a groove in one of the hub ends so that the second hub end can then be moved against the other side of the primary seal ring. Once the seal ring is positioned between the pipe hubs, the pipe hubs can be moved about the seal ring due to the flat sides of the arms of the tool. The tool eliminates the chances of damaging and contaminating seal rings being installed within pipe hubs that are being attached to one another.

  5. Biohazards Assessment in Large-Scale Zonal Centrifugation

    PubMed Central

    Baldwin, C. L.; Lemp, J. F.; Barbeito, M. S.

    1975-01-01

    A study was conducted to determine the biohazards associated with use of the large-scale zonal centrifuge for purification of moderate risk oncogenic viruses. To safely and conveniently assess the hazard, coliphage T3 was substituted for the virus in a typical processing procedure performed in a National Cancer Institute contract laboratory. Risk of personnel exposure was found to be minimal during optimal operation but definite potential for virus release from a number of centrifuge components during mechanical malfunction was shown by assay of surface, liquid, and air samples collected during the processing. High concentration of phage was detected in the turbine air exhaust and the seal coolant system when faulty seals were employed. The simulant virus was also found on both centrifuge chamber interior and rotor surfaces. Images PMID:1124921

  6. 48 CFR 16.103 - Negotiating contract type.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... CONTRACTING METHODS AND CONTRACT TYPES TYPES OF CONTRACTS Selecting Contract Types 16.103 Negotiating contract... basic profit motive of business enterprise, shall be used when the risk involved is minimal or can be...) Contracts on a firm fixed-price basis other than those for major systems or research and development, and (3...

  7. Development of braided rope seals for hypersonic engine applications: Flow modeling

    NASA Technical Reports Server (NTRS)

    Mutharasan, Rajakkannu; Steinetz, Bruce M.; Tao, Xiaoming; Du, Guang-Wu; Ko, Frank

    1992-01-01

    A new type of engine seal is being developed to meet the needs of advanced hypersonic engines. A seal braided of emerging high temperature ceramic fibers comprised of a sheath-core construction was selected for study based on its low leakage rates. Flexible, low-leakage, high temperature seals are required to seal the movable engine panels of advanced ramjet-scramjet engines either preventing potentially dangerous leakage into backside engine cavities or limiting the purge coolant flow rates through the seals. To predict the leakage through these flexible, porous seal structures new analytical flow models are required. Two such models based on the Kozeny-Carman equations are developed herein and are compared to experimental leakage measurements for simulated pressure and seal gap conditions. The models developed allow prediction of the gas leakage rate as a function of fiber diameter, fiber packing density, gas properties, and pressure drop across the seal. The first model treats the seal as a homogeneous fiber bed. The second model divides the seal into two homogeneous fiber beds identified as the core and the sheath of the seal. Flow resistances of each of the main seal elements are combined to determine the total flow resistance. Comparisons between measured leakage rates and model predictions for seal structures covering a wide range of braid architectures show good agreement. Within the experimental range, the second model provides a prediction within 6 to 13 percent of the flow for many of the cases examined. Areas where future model refinements are required are identified.

  8. Giga-ohm seals on intracellular membranes: a technique for studying intracellular ion channels in intact cells.

    PubMed

    Jonas, E A; Knox, R J; Kaczmarek, L K

    1997-07-01

    A method is outlined for obtaining giga-ohm seals on intracellular membranes in intact cells. The technique employs a variant of the patch-clamp technique: a concentric electrode arrangement protects an inner patch pipette during penetration of the plasma membrane, after which a seal can be formed on an internal organelle membrane. Using this technique, successful recordings can be obtained with the same frequency as with conventional patch clamping. To localize the position of the pipette within cells, lipophilic fluorescent dyes are included in the pipette solution. These dyes stain the membrane of internal organelles during seal formation and can then be visualized by video-enhanced or confocal imaging. The method can detect channels activated by inositol trisphosphate, as well as other types of intracellular membrane ion channel activity, and should facilitate studies of internal membranes in intact neurons and other cell types.

  9. Mobile LNG (liquified natural gas) gelator. Final report, July 1980-September 1981

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

    Rudnicki, M.I.; Hoffman, L.C.; Newton, R.A.

    1981-12-01

    Gelled liquified natural gas (GELNG) offers potential safety advantages over LNG in the case of an accidental spill. GELNG has shown reduced spread area, lower vaporization rate, and crack sealing capability relative to the ungelled material. The purpose of this contract was to develop a mobile, continuous gelator which would produce a minimum of one cubic meter per hour of GELNG; previously, GELNG had been produced in small quantities by batch processes. Major achievements under the contract were the design and construction of the mobile gelator, checkout of the system with liquid nitrogen, and testing of the system on LNG.more » GELNG was not produced in the test series.« less

  10. Frequency dependence of excitation-contraction of multicellular smooth muscle preparations: the relevance to bipolar electrosurgery.

    PubMed

    Vladimirova, Irina A; Lankin, Yuri N; Philyppov, Igor B; Sushiy, Lyudmyla F; Shuba, Yaroslav M

    2014-01-01

    Bipolar electrosurgical tissue welding uses forceps-like electrodes for grasping the tissues and delivering high-frequency electric current (HFEC) to produce local heat, desiccation, and protein denaturation, resulting in the fusion of the contacting tissues. Although in this technique no electric current is flowing through the whole body to cause electric injury, depending on the frequency of applied energy, it may produce local excitation of intramural nerves, which can propagate beyond the surgical site potentially causing harmful effects. The effects of varying frequency of HFEC on tissue excitability in bipolar electrosurgical modality were studied in vitro using electric field stimulation (EFS) method on multicellular smooth muscle strips of rat vas deferens. Contractile response to 5-s-long sine wave EFS train was taken as the measure of excitation of intramural nerves. EFS-induced contraction consisted of phasic and tonic components. The amplitude of both components decreased with increasing frequency, with tonic component disappearing at about 10 kHz and phasic component at about 50 kHz. Because components of EFS-induced contraction depend on different neurotransmitters, this indicates that various neurotransmitter systems are characterized by distinct frequency dependence, but above 50 kHz they all become inactivated. Bipolar electrosurgical sealing of porcine gut showed no difference in the structure of seal area at HFEC of 67 and 533 kHz. EFS frequency of 50 kHz represents the upper limit for excitation. HFEC above 50 kHz is safe to use for bipolar electrosurgical tissue welding without concerns of excitation propagating beyond the surgical site. Copyright © 2014 Elsevier Inc. All rights reserved.

  11. Thermally stable electrolytes for rechargeable lithium batteries, phase 2

    NASA Technical Reports Server (NTRS)

    Dominey, L. A.; Goldman, J. L.; Koch, V. R.

    1989-01-01

    During the second year of research under NASA SBIR Contract NAS7-967, Covalent Associates and NASA contract monitors at the Jet Propulsion Laboratory agreed to perform an evaluation of the three best electrolytes developed during Phase 2. Due to the extensive period of time required to collect meaningful cycling data, we realized the study would extend well beyond the original formal end of the Phase 2 program (August 31, 1988). The substitution of this effort in lieu of an earlier proposed 20-cell final deliverable is formally documented in Modification No. 1 of Contract NAS7-967 as task 7. This Addendum contains the results of the cycling studies performed at Covalent Associates. In addition, sealed ampoules of each of these three electrolytes were delivered to the Jet Propulsion Laboratory Electrochemical Power Group. Their concurrent evaluation in a different test vehicle has also been recently concluded and their results are also summarized herein.

  12. Thermally stable electrolytes for rechargeable lithium batteries, phase 2

    NASA Astrophysics Data System (ADS)

    Dominey, L. A.; Goldman, J. L.; Koch, V. R.

    1989-09-01

    During the second year of research under NASA SBIR Contract NAS7-967, Covalent Associates and NASA contract monitors at the Jet Propulsion Laboratory agreed to perform an evaluation of the three best electrolytes developed during Phase 2. Due to the extensive period of time required to collect meaningful cycling data, we realized the study would extend well beyond the original formal end of the Phase 2 program (August 31, 1988). The substitution of this effort in lieu of an earlier proposed 20-cell final deliverable is formally documented in Modification No. 1 of Contract NAS7-967 as task 7. This Addendum contains the results of the cycling studies performed at Covalent Associates. In addition, sealed ampoules of each of these three electrolytes were delivered to the Jet Propulsion Laboratory Electrochemical Power Group. Their concurrent evaluation in a different test vehicle has also been recently concluded and their results are also summarized herein.

  13. Factors Affecting Haul-Out Behavior of Harbor Seals (Phoca vitulina) in Tidewater Glacier Inlets in Alaska: Can Tourism Vessels and Seals Coexist?

    PubMed Central

    2015-01-01

    Large numbers of harbor seals (Phoca vitulina) use habitat in tidewater glaciers in Alaska for pupping, breeding, and molting. Glacial fjords are also popular tourist destinations; however, visitation by numerous vessels can result in disturbance of seals during critical life-history phases. We explored factors affecting haul-out behavior of harbor seals at a glacial site frequented by tourism vessels. In 2008-10, we deployed VHF transmitters on 107 seals in Endicott Arm, Alaska. We remotely monitored presence and haul-out behavior of tagged seals and documented vessel presence with time-lapse cameras. We evaluated the influence of environmental and physical factors on the probability of being hauled out, duration of haul-out bouts, and as factors associated with the start and end of a haulout. Location, season, hour, and interactions of location by year, season, hour, and sex significantly influenced haul-out probability, as did ice, weather, and vessels. Seals were more likely to be hauled out with greater ice availability during the middle of the day, and less likely to be hauled out if vessels were present. Cruise ships had the strongest negative effect; however, most vessel types negatively affected haul-out probability. Haul-out duration was longest in association with starting on incoming tides, clear skies, no precipitation, occurring in the middle of the day, and ending in the late afternoon or evening. End of haulouts was associated with increasing cloud cover, low ice availability, and vessel presence; large-sized tourism vessels or all-vessel-types combined were significant predictors of ending a haul-out bout. Probability of being hauled out was highest in June, during pupping season. Potential disturbances of harbor seals could be reduced, enabling longer resting times for seals and fewer interruptions for nursing pups, if vessels focused the majority of visits to glacial habitat to before or after the hours of 08:00-17:00 or, less optimally, 09:00-16:00. PMID:26017404

  14. Factors Affecting Haul-Out Behavior of Harbor Seals (Phoca vitulina) in Tidewater Glacier Inlets in Alaska: Can Tourism Vessels and Seals Coexist?

    PubMed

    Blundell, Gail M; Pendleton, Grey W

    2015-01-01

    Large numbers of harbor seals (Phoca vitulina) use habitat in tidewater glaciers in Alaska for pupping, breeding, and molting. Glacial fjords are also popular tourist destinations; however, visitation by numerous vessels can result in disturbance of seals during critical life-history phases. We explored factors affecting haul-out behavior of harbor seals at a glacial site frequented by tourism vessels. In 2008-10, we deployed VHF transmitters on 107 seals in Endicott Arm, Alaska. We remotely monitored presence and haul-out behavior of tagged seals and documented vessel presence with time-lapse cameras. We evaluated the influence of environmental and physical factors on the probability of being hauled out, duration of haul-out bouts, and as factors associated with the start and end of a haulout. Location, season, hour, and interactions of location by year, season, hour, and sex significantly influenced haul-out probability, as did ice, weather, and vessels. Seals were more likely to be hauled out with greater ice availability during the middle of the day, and less likely to be hauled out if vessels were present. Cruise ships had the strongest negative effect; however, most vessel types negatively affected haul-out probability. Haul-out duration was longest in association with starting on incoming tides, clear skies, no precipitation, occurring in the middle of the day, and ending in the late afternoon or evening. End of haulouts was associated with increasing cloud cover, low ice availability, and vessel presence; large-sized tourism vessels or all-vessel-types combined were significant predictors of ending a haul-out bout. Probability of being hauled out was highest in June, during pupping season. Potential disturbances of harbor seals could be reduced, enabling longer resting times for seals and fewer interruptions for nursing pups, if vessels focused the majority of visits to glacial habitat to before or after the hours of 08:00-17:00 or, less optimally, 09:00-16:00.

  15. Experimental and numerical study on the performance of the smooth-land labyrinth seal

    NASA Astrophysics Data System (ADS)

    Szymanski, A.; Dykas, S.; Wróblewski, W.; Majkut, M.; Strozik, M.

    2016-10-01

    In turbomachinery the secondary flow system includes flow phenomena occurring outside the main channel, where the gaseous medium performs work on blades. Secondary air distribution constitutes a very complex and closely interrelated system that affects most of the gas turbine components. One of the most important examples of the secondary flow is leakage occurring in seals, e.g. at the rotor and stator tips, on the shaft or on the sides of the blade rim. Owing to its simplicity, low price, easy maintenance and high temperature capability, the labyrinth seal is a prime sealing solution that may be selected from numerous types of sealing structures applied in turbomachinery. For this reason, an experimental study of this particular structure has been carried out. The paper presents leakage performance of the smooth-land labyrinth seal.

  16. Sealing in Turbomachinery

    NASA Technical Reports Server (NTRS)

    Chupp, Raymond E.; Hendricks, Robert C.; Lattime, Scott B.; Steinetz, Bruce M.

    2006-01-01

    Clearance control is of paramount importance to turbomachinery designers and is required to meet today's aggressive power output, efficiency, and operational life goals. Excessive clearances lead to losses in cycle efficiency, flow instabilities, and hot gas ingestion into disk cavities. Insufficient clearances limit coolant flows and cause interface rubbing, overheating downstream components and damaging interfaces, thus limiting component life. Designers have put renewed attention on clearance control, as it is often the most cost effective method to enhance system performance. Advanced concepts and proper material selection continue to play important roles in maintaining interface clearances to enable the system to meet design goals. This work presents an overview of turbomachinery sealing to control clearances. Areas covered include: characteristics of gas and steam turbine sealing applications and environments, benefits of sealing, types of standard static and dynamics seals, advanced seal designs, as well as life and limitations issues.

  17. Antimasking aspects of harp seal (Pagophilus groenlandicus) underwater vocalizations.

    PubMed

    Serrano, Arturo; Terhune, John M

    2002-12-01

    Underwater sounds are very important in social communication of harp seals (Pagophilus groenlandicus) because they are the main means of long- and short-distance communication. Individual harp seals must try to avoid being masked and emit only those calls that will benefit them. Underwater vocalizations of harp seals were recorded during the breeding season. The physical characteristics associated with antimasking attributes of 16 call types were examined. Rising frequency or increasing amplitude within calls were not common. Most of the calls ended abruptly (range 145-966 dB/s), but call onset was more gradual. At high calling rates (95.1-135 calls/min) there were significantly more calls overlapping temporally than at medium (75.1-95 calls/min) or low (35-75 calls/min) calling rates, but even at the highest calling rates, 79.1% of the calls were not overlapped. When 2, 3, or 4 calls overlapped, there were significantly fewer frequency separations of less than 1/3 octave than would be expected by chance. This is important because sounds that are separated by less than 1/3 octave likely mask each other. When 2-4 calls are occurring simultaneously, only 4.5% to 14.2% are masked by virtue of being within 1/3 octave from their nearest neighbor. None of the overlappping calls was of the same type. This suggests that the seals are actively listening to each other's calls and are not randomly using the different call types. Harp seals use frequency and temporal separation in conjunction with a wide vocal repertoire to avoid masking each other.

  18. Antimasking aspects of harp seal (Pagophilus groenlandicus) underwater vocalizations

    NASA Astrophysics Data System (ADS)

    Serrano, Arturo; Terhune, John M.

    2002-12-01

    Underwater sounds are very important in social communication of harp seals (Pagophilus groenlandicus) because they are the main means of long- and short-distance communication. Individual harp seals must try to avoid being masked and emit only those calls that will benefit them. Underwater vocalizations of harp seals were recorded during the breeding season. The physical characteristics associated with antimasking attributes of 16 call types were examined. Rising frequency or increasing amplitude within calls were not common. Most of the calls ended abruptly (range 145-966 dB/s), but call onset was more gradual. At high calling rates (95.1-135 calls/min) there were significantly more calls overlapping temporally than at medium (75.1-95 calls/min) or low (35-75 calls/min) calling rates, but even at the highest calling rates, 79.1% of the calls were not overlapped. When 2, 3, or 4 calls overlapped, there were significantly fewer frequency separations of less than 1/3 octave than would be expected by chance. This is important because sounds that are separated by less than 1/3 octave likely mask each other. When 2-4 calls are occurring simultaneously, only 4.5% to 14.2% are masked by virtue of being within 1/3 octave from their nearest neighbor. None of the overlappping calls was of the same type. This suggests that the seals are actively listening to each other's calls and are not randomly using the different call types. Harp seals use frequency and temporal separation in conjunction with a wide vocal repertoire to avoid masking each other.

  19. Pilot cryo tunnel: Attachments, seals, and insulation

    NASA Technical Reports Server (NTRS)

    Wilson, J. F.; Ware, G. D.; Ramsey, J. W., Jr.

    1974-01-01

    Several different tests are described which simulated the actual configuration of a cryogenic wind tunnel operating at pressures up to 5 atmospheres (507 kPa) and temperatures from -320 F (78K) to 120 F (322K) in order to determine compatible bolting, adequate sealing, and effective insulating materials. The evaluation of flange attachments (continuous threaded studs) considered bolting based on compatible flanges, attachment materials, and prescribed bolt elongations. Various types of seals and seal configurations were studied to determine suitability and reusability under the imposed pressure and temperature loadings. The temperature profile was established for several materials used for structural supports.

  20. Investigation of package sealing using organic adhesives

    NASA Technical Reports Server (NTRS)

    Perkins, K. L.; Licari, J. J.

    1977-01-01

    A systematic study was performed to evaluate the suitability of adhesives for sealing hybrid packages. Selected adhesives were screened on the basis of their ability to seal gold-plated Kovar butterfly-type packages that retain their seal integrity after individual exposures to increasingly severe temperature-humidity environments. Tests were also run using thermal shock, temperature cycling, mechanical shock and temperature aging. The four best adhesives were determined and further tested in a 60 C/98% RH environment and continuously monitored in regard to moisture content. Results are given, however, none of the tested adhesives passed all the tests.

  1. Prime Contract Awards by Service Category and Federal Supply Classification, Fiscal Years 1982, 1983, 1984, 1985.

    DTIC Science & Technology

    1985-01-01

    GAMES TOYS AND WHEELED GOODS 711 351 568 380 7830 RECREATIONAL AND GYMNASTIC EQUIPMENT 3,938 2,498 5.248 3,790 TOTAL 8,292 5.278 7,703 6.107 79 CLEANING...PAINTS DOPES VARNISHES AND RELATED PROD 10,453 3.478 3.662 5,123 8020 PAINT AND ARTISTS BRUSHES 11 0 0 0 8030 PRESERVATIVE AND SEALING COMPOUNDS 2.169

  2. Hole of Government: Sealing the Gap in U.S. Stability Operations

    DTIC Science & Technology

    2010-06-15

    including suggestions for reducing this burden, to Washington Headquarters Services, Directorate for Information Operations and Reports, 1215... Gap in U.S. Stability Operations” 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR (S) Commander Patrick J...THE GAP IN U.S. STABILITY OPERATIONS by Patrick J. Hannifin CDR, USN A paper submitted to the Faculty of the Joint Advanced

  3. Rocketdyne RBCC Engine Concept Development

    NASA Technical Reports Server (NTRS)

    Ratckin, G.; Goldman, A.; Ortwerth, P.; Weisberg, S.

    1999-01-01

    Boeing Rocketdyne is pursuing the development of Rocket Based Combined Cycle (RBCC), propulsion systems as demonstrated by significant contract work in the hypersonic arena (ART, NASP, SCT, system studies) and over 12 years of steady company discretionary investment. The Rocketdyne concept is a fixed geometry integrated rocket, ramjet, scramjet which is hydrogen fueled and uses hydrogen regenerative cooling. The baseline engine structural configuration uses an integral structure that eliminates panel seals. seal purge gas, and closeout side attachments. Rocketdyne's experimental RBCC engine (Engine A5) was constructed under contract with the NASA Marshall Space Flight Center. Engine A5 models the complete flight engine flowpath consisting of an inlet, isolator, airbreathing combustor and nozzle. High performance rocket thrusters are integrated into the engine to enable both air-augmented rocket (AAR) and pure rocket operation. Engine A5 was tested in CASL's new FAST facility as an air-augmented rocket, a ramjet and a pure rocket. Measured performance demonstrated vision vehicle performance levels for Mach 3 AAR operation and ramjet operation from Mach 3 to 4. Rocket mode performance was above predictions. For the first time. testing also demonstrated transition from AAR operation to ramjet operation. This baseline configuration has also been shown, in previous testing, to perform well in the scramjet mode.

  4. 48 CFR 16.203-4 - Contract clauses.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... AND CONTRACT TYPES TYPES OF CONTRACTS Fixed-Price Contracts 16.203-4 Contract clauses. (a) Adjustment... must agree in writing on the identity of the standard supplies and the corresponding contract line...) The contracting officer shall describe in detail in the contract Schedule— (i) The types of labor and...

  5. 48 CFR 43.103 - Types of contract modifications.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... only by the contracting officer. Unilateral modifications are used, for example, to— (1) Make... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Types of contract... CONTRACT MANAGEMENT CONTRACT MODIFICATIONS General 43.103 Types of contract modifications. Contract...

  6. 48 CFR 43.103 - Types of contract modifications.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... only by the contracting officer. Unilateral modifications are used, for example, to— (1) Make... 48 Federal Acquisition Regulations System 1 2011-10-01 2011-10-01 false Types of contract... CONTRACT MANAGEMENT CONTRACT MODIFICATIONS General 43.103 Types of contract modifications. Contract...

  7. Migration of polyethylene debris along well-fixed cemented implants.

    PubMed

    Massin, P; Viguier, E; Flautre, B; Hardouin, P; Astoin, E; Duponchel, B

    2004-02-15

    Implants, consisting of smooth Inox cylinders, were cemented into the lower femur and upper tibia of nine sheep to study the distal migration of polyethylene particles. Some implants had a titanium-bead porous coat at the proximal end. These were of three types: In the first type, the porous coat was covered with hydroxyapatite to obtain a bony seal; the second type was prepared for a polymethylmethacrylate seal; in the third type, the porous zone was surrounded by a 2-mm-thick space to allow the formation of a fibrous seal. Small polyethylene particles were injected into the knees once a week during the third and fourth months after implantation. The animals were euthanized 2 months later. Major longitudinal sections of the implants and the surrounding bone were examined under a polarized light microscope. Birefringent particles were counted at the cement-bone and cement-implant interfaces. Osteolysis was not observed. None of the seals significantly decreased the migration of particles around the cemented part of the implants. Particles were observed in cement fissures and vacuoles. They migrated at both interfaces and in the bone itself. They were visible in marrow spaces between bone trabeculae. Copyright 2003 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 68B: 140-148, 2004

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

    Smartt, Heidi A.; Romero, Juan A.; Custer, Joyce Olsen

    Containment/Surveillance (C/S) measures are critical to any verification regime in order to maintain Continuity of Knowledge (CoK). The Ceramic Seal project is research into the next generation technologies to advance C/S, in particular improving security and efficiency. The Ceramic Seal is a small form factor loop seal with improved tamper-indication including a frangible seal body, tamper planes, external coatings, and electronic monitoring of the seal body integrity. It improves efficiency through a self-securing wire and in-situ verification with a handheld reader. Sandia National Laboratories (SNL) and Savannah River National Laboratory (SRNL), under sponsorship from the U.S. National Nuclear Security Administrationmore » (NNSA) Office of Defense Nuclear Nonproliferation Research and Development (DNN R&D), have previously designed and have now fabricated and tested Ceramic Seals. Tests have occurred at both SNL and SRNL, with different types of tests occurring at each facility. This interim report will describe the Ceramic Seal prototype, the design and development of a handheld standalone reader and an interface to a data acquisition system, fabrication of the seals, and results of initial testing.« less

  9. Tamper-indicating seals : practices, problems, and standards

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

    Johnston, R. G.

    2003-01-01

    Tamper-indicating seals have been used by customs officials for over 7,000 years. Today, seals are widely used to help counter theft, smuggling, sabotage, vandalism, terrorism, and espionage. Despite their antiquity and modern widespread use, however, there remains considerable confusion about seals, as well as a lot of misconceptions, wishful thinking, sloppy terminology, and poor practice. The absence of meaningful norms and standards, together with the surprisingly limited amount of research and development (R&D) in the field of tamper detection, has also hindered the effective use of seals. The Vulnerability Assessment Team (VAT) at Los Alamos National Laboratory has intensively studiedmore » tamper-indicating seals for the last 12 years. We have engaged in vulnerability assessments, R&D, consulting, and training for over two dozen United States government agencies and private companies, as well as for the International Atomic Energy Agency (IAEA) and Euratom. The VAT has also analyzed over 200 different types of seals in detail. This paper summarizes some of our conclusions, recommendations, and warnings regarding seals and tamper detection.« less

  10. Assessing MMOD Impacts on Seal Performance

    NASA Technical Reports Server (NTRS)

    deGroh, Henry C., III; Daniels, C.; Dunlap, P.; Steinetz, B.

    2007-01-01

    The elastomer seal needed to seal in cabin air when NASA s Crew Exploration Vehicle is docked is exposed to space prior to docking. While open to space, the seal might be hit by orbital debris or meteoroids. The likelihood of damage of this type depends on the size of the particle. Our campaign is designed to find the smallest particle that will cause seal failure resulting in loss of mission. We will then be able to estimate environmental risks to the seal. Preliminary tests indicate seals can withstand a surprising amount of damage and still function. Collaborations with internal and external partners are in place and include seal leak testing, modeling of the space environment using a computer code known as BUMPER, and hypervelocity impact (HVI) studies at Caltech. Preliminary work at White Sands Test Facility showed a 0.5 mm diameter HVI damaged areas about 7 times that diameter, boring deep (5 mm) into elastomer specimens. BUMPER simulations indicate there is a 1 in 1440 chance of getting hit by a particle of diameter 0.08 cm for current Lunar missions; and 0.27 cm for a 10 year ISS LIDS seal area exposure.

  11. Measure Guideline. Air Sealing Attics in Multifamily Buildings

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

    Otis, Casey; Maxwell, Sean

    2012-06-01

    This Building America Measure Guideline is intended for owners, builders, contractors, homeowners, and other stakeholders in the multifamily building industry, and focuses on challenges found in existing buildings for a variety of housing types. It explains why air sealing is desirable, explores related health and safety issues, and identifies common air leakage points in multifamily building attics. In addition, it also gives an overview of materials and techniques typically used to perform air sealing work.

  12. Measure Guideline: Air Sealing Attics in Multifamily Buildings

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

    Otis, C.; Maxwell, S.

    2012-06-01

    This Building America Measure Guideline is intended for owners, builders, contractors, homeowners, and other stakeholders in the multifamily building industry, and focuses on challenges found in existing buildings for a variety of housing types. It explains why air sealing is desirable, explores related health and safety issues, and identifies common air leakage points in multifamily building attics. In addition, it also gives an overview of materials and techniques typically used to perform air sealing work.

  13. Dry-running gas seals save $200,000/yr in retrofit hydrogen recycle compressor

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

    Pennacchi, R.P.; Germain, A.

    1987-10-01

    Texaco Chemical Company was using three drums of oil per day in the seal oil system of a hydrogen recycle compressor, resulting in maintenance and operational expenses of more than $160,000 per year. Running 24 hours/day, 365 days/yr, the 26-yr-old compressor is the heart of the benzene manufacturing process unit at the Port Arthur, Texas plant. In the event of an unscheduled shutdown, the important aromatics unit process would halt and cause production losses of thousands of dollars per day. In addition, the close monitoring and minimization of leakage are essential since the gas consists of over 75% hydrogen, withmore » methane, ethane, propane, isobutane, N-butane and pentanes. Texaco Chemical Company decided that retrofit of the hydrogen recycle compressor should be undertaken if the system could be developed to sharply reduce operations and maintenance costs, and increase efficiencies. Texaco engineers selected a dry running-type gas sealing system developed for pipeline compressors in the United States, Canada, and overseas. A tandem-type sealing system was designed to meet specific needs of a hydrogen recycle compressor. The retrofit was scheduled for August 1986 to coincide with the plant's preventative maintenance program. The seal system installation required five days. The retrofit progressed according to schedule, with no problems experienced at the first and several startups since the initial installation. Oil consumption has been eliminated, along with seal support and parasitic energy requirements. With the savings in seal oil, energy, operations and maintenance, payback period for the retrofit sealing system was just over six months. Savings are expected to continue at an annual rate of over $200,000.« less

  14. SRB attach ring phenolic TPS fishtail seal evaluation tests

    NASA Technical Reports Server (NTRS)

    Karu, Z. S.

    1982-01-01

    The SRB attach ring is thermally protected with layered phenolic cloth fairings that are fastened to the ring. The gap between the fairings and the motor case is closed off with a rubber seal of a fishtail cross sectional shape bonded to the phenolic. On both the STS-1 and STS-2 flights this gap was discovered to vary anywhere from an intended gap of 0.375 in. to an actual measured gap of 0.60 in. due to tolerances. Tests were conducted with and without a 0.25 in. thick cork shim placed under the seal with a 0.60 in. gap under the phenolic TPS to determine and compare the performance of the seal in the two different configurations. To alleviate the difficult and costly procedure of installing the cork shim under the seal, especially after phenolic TPS mounting on the attach ring, large fishtail seals of idential Elder gray silicon material and two different hardnesses were tested. A similar matrix of tests was conducted with this new large fishtail seal, and seals with both type hardnesses performed well regardless of whether or not the seal was bonded in the phenolic at the front of the seal groove. Similar results had been obtained with the original small fishtail seal which performed adequately with the 0.25 in. cork shim under it.

  15. Modeling and Evaluation of Canted Coil Springs as High Temperature Seal Preloading Devices

    NASA Technical Reports Server (NTRS)

    Oswald, Jay J.; Mullen, Robert L.; Dunlap, Patrick H., Jr.; Steinetz, Bruce M.

    2004-01-01

    Future reusable launch vehicles will require advanced structural seals. This includes propulsion seals along edges and hinge lines in hypersonic engines, and control surface seals for movable flaps and elevons on proposed reentry vehicles. Seals must remain in sealing engagement with opposing surfaces, for multiple missions, even though the seal gap may be opening and closing due to thermal and structural loads. To meet this requirement either the seals themselves must be resilient or there must be a resilient structural element behind the seals. Case Western Reserve University is working with NASA s Glenn Research Center to develop more resilient high temperature seal components and preloading devices. Results are presented for a finite element analysis of a canted coil spring that is being considered as a high temperature seal preloading device. This type of spring is a leading candidate due to its ability to provide nearly constant force over a large deflection. The finite element analyses were verified by comparing them to experimental results of canted coil springs of three different stiffnesses, measured at Glenn Research Center. Once validated the parameterized model was combined with a scripting algorithm to assess the effects of key spring design variables (wire diameter, coils per inch, cant amplitude, eccentricity, and spring width) on spring stiffness and maximum Von Mises stress to aid in subsequent design.

  16. Design and analysis of seals for extended service life

    NASA Technical Reports Server (NTRS)

    Bower, Mark V.

    1992-01-01

    Space Station Freedom is being developed for a service life of up to thirty years. As a consequence, the design requirements for the seals to be used are unprecedented. Full scale testing to assure the selected seals can satisfy the design requirements are not feasible. As an alternative, a sub-scale test program has been developed by MSFC to calibrate the analysis tools to be used to certify the proposed design. This research has been conducted in support of the MSFC Integrated Seal Test Program. The ultimate objective of this research is to correlate analysis and test results to qualify the analytical tools, which in turn, are to be used to qualify the flight hardware. This research is totally focused on O-rings that are compressed by perpendicular clamping forces. In this type of seal the O-ring is clamped between the sealing surfaces by loads perpendicular to the circular cross section.

  17. Apparatus and method for sealing perforated well casing

    DOEpatents

    Blount, Curtis G.; Benham, Robert A.; Brock, Jerry L.; Emerson, John A.; Ferguson, Keith R.; Scheve, Donald F.; Schmidt, Joseph H.; Schuler, Karl W.; Stanton, Philip L.

    1997-01-01

    Perforations and other openings in well casings, liners and other conduits may be substantially blocked or sealed to prevent fluid flow between the casing or liner interior and an earth formation by placing a radially expansible sleeve adjacent the perforations or openings and urging the sleeve into forcible engagement with the casing or inner wall using an explosive charge. An apparatus including a radially contracted sleeve formed by a coiled plate member or a tubular member having flutes defined by external and internal folds, may be deployed into a well casing or liner through a production or injection tubing string and on the end of a flexible cable or coilable tubing. An explosive charge disposed on the apparatus and within the sleeve may be detonated to urge the sleeve into forcible engagement with the casing inner wall.

  18. Apparatus and method for sealing perforated well casing

    DOEpatents

    Blount, C.G.; Benham, R.A.; Brock, J.L.; Emerson, J.A.; Ferguson, K.R.; Scheve, D.F.; Schmidt, J.H.; Schuler, K.W.; Stanton, P.L.

    1997-03-25

    Perforations and other openings in well casings, liners and other conduits may be substantially blocked or sealed to prevent fluid flow between the casing or liner interior and an earth formation by placing a radially expansible sleeve adjacent the perforations or openings and urging the sleeve into forcible engagement with the casing or inner wall using an explosive charge. An apparatus including a radially contracted sleeve formed by a coiled plate member or a tubular member having flutes defined by external and internal folds, may be deployed into a well casing or liner through a production or injection tubing string and on the end of a flexible cable or coilable tubing. An explosive charge disposed on the apparatus and within the sleeve may be detonated to urge the sleeve into forcible engagement with the casing inner wall. 17 figs.

  19. A hybrid floating brush seal (HFBS) for improved sealing and wear performance in turbomachinery applications

    NASA Astrophysics Data System (ADS)

    Lattime, Scott Byran

    A conceptually new type of seal has been developed for gas turbine applications which dramatically reduces wear and leakage associated with current labyrinth and brush seal technologies. The Hybrid Floating Brush Seal (HFBS) combines brush seal and film riding face seal technologies to create a hybrid seal that allows both axial and radial excursions of the sealed shaft, while simultaneously eliminating interface surface speeds (friction and heat) between the rotor and the brush material that characterize standard brush seal technology. A simple test rig was designed to evaluate feasibility of the HFBS under relatively low pressures and rotational speeds (50psig, 5krpm). A second test stand was created to study the effects of centrifugal force on bristle deflection. A third test facility was constructed for prototype development and extensive room temperature testing at moderate pressures and fairly high rotational speeds (100psig, 40krpm). This test rig also allowed the evaluation of the HFBS during axial movement of a rotating shaft. An analytical model to predict the effects of centrifugal force on the bristles of a rotating brush seal was developed. Room temperature analysis of the HFBS proved successful for relatively high operating rotational velocities at moderate pressures with very acceptable leakage rates for gas turbine engines. Brush seals were able to track rotor speeds up to 24krpm while maintaining sealing integrity. The HFBS's ability to function under axial shaft displacement and synchronous dynamic radial loading was also proven successful. Hydrodynamic performance of the face seal was proven to provide adequate stiffness and load carrying capacity to keep the brush seal from contacting the face seal at pressure drops across the brush of up to 100psi. Leakage performance over standard brush seal and labyrinth technology was quite dramatic. The HFBS showed its sealing advantage using much higher radial interference between the rotor and the bristle bore over standard brush seal designs. Experimental results of the HFBS showed leakage reductions of 6 to 7 times that of a standard brush seal at the same operating pressure ratios and rotational speed and an order of magnitude less than numerical predictions of a standard labyrinth seal. (Abstract shortened by UMI.)

  20. Brucella Antibodies in Alaskan True Seals and Eared Seals-Two Different Stories.

    PubMed

    Nymo, Ingebjørg H; Rødven, Rolf; Beckmen, Kimberlee; Larsen, Anett K; Tryland, Morten; Quakenbush, Lori; Godfroid, Jacques

    2018-01-01

    Brucella pinnipedialis was first isolated from true seals in 1994 and from eared seals in 2008. Although few pathological findings have been associated with infection in true seals, reproductive pathology including abortions, and the isolation of the zoonotic strain type 27 have been documented in eared seals. In this study, a Brucella enzyme-linked immunosorbent assay (ELISA) and the Rose Bengal test (RBT) were initially compared for 206 serum samples and a discrepancy between the tests was found. Following removal of lipids from the serum samples, ELISA results were unaltered while the agreement between the tests was improved, indicating that serum lipids affected the initial RBT outcome. For the remaining screening, we used ELISA to investigate the presence of Brucella antibodies in sera of 231 eared and 1,412 true seals from Alaskan waters sampled between 1975 and 2011. In eared seals, Brucella antibodies were found in two Steller sea lions ( Eumetopias jubatus ) (2%) and none of the 107 Northern fur seals ( Callorhinus ursinus ). The low seroprevalence in eared seals indicate a low level of exposure or lack of susceptibility to infection. Alternatively, mortality due to the Brucella infection may remove seropositive animals from the population. Brucella antibodies were detected in all true seal species investigated; harbor seals ( Phoca vitulina ) (25%), spotted seals ( Phoca largha ) (19%), ribbon seals ( Histriophoca fasciata ) (16%), and ringed seals ( Pusa hispida hispida ) (14%). There was a low seroprevalence among pups, a higher seroprevalence among juveniles, and a subsequent decreasing probability of seropositivity with age in harbor seals. Similar patterns were present for the other true seal species; however, solid conclusions could not be made due to sample size. This pattern is in accordance with previous reports on B. pinnipedialis infections in true seals and may suggest environmental exposure to B. pinnipedialis at the juvenile stage, with a following clearance of infection. Furthermore, analyses by region showed minor differences in the probability of being seropositive for harbor seals from different regions regardless of the local seal population trend, signifying that the Brucella infection may not cause significant mortality in these populations. In conclusion, the Brucella infection pattern is very different for eared and true seals.

  1. The evaluation of dentinal tubule occlusion by desensitizing agents: a real-time measurement of dentinal fluid flow rate and scanning electron microscopy.

    PubMed

    Kim, S Y; Kim, E J; Kim, D S; Lee, I B

    2013-01-01

    The aims of this study were to examine changes in dentinal fluid flow (DFF) during the application of a desensitizing agent and to compare the permeability reduction levels among different types of desensitizing agents. A cervical cavity was prepared for the exposure of cervical dentin on an extracted human premolar connected to a subnanoliter fluid flow measuring device under 20 cm of water pressure. The cavity was acid-etched with 32% phosphoric acid to make dentin highly permeable. The different types of desensitizing agents that were applied on the cavity were Seal&Protect as the light-curing adhesive type, SuperSeal and BisBlock as oxalate types, Gluma Desensitizer as the protein-precipitation type, and Bi-Fluoride 12 as the fluoride type. DFF was measured from the time before the application of the desensitizing agent throughout the application procedure to five minutes after the application. The characteristics of dentinal tubule occlusion of each desensitizing agent were examined by scanning electron microscopy. The DFF rate after each desensitizing agent application was significantly reduced when compared to the initial DFF rate before application for all of the desensitizing agents (p<0.05). Seal&Protect showed a greater reduction in the DFF rate when compared to Gluma Desensitizer and Bi-Fluoride 12 (p<0.05). SuperSeal and BisBlock exhibited a greater reduction in DFF rate when compared to Bi-Fluoride 12 (p<0.05). The dentin hypersensitivity treatment effects of the employed desensitizing agents in this study were confirmed through real-time measurements of DFF changes. The light-curing adhesive and oxalate types showed greater reduction in the DFF rate than did the protein-precipitation and fluoride types.

  2. 48 CFR 46.202 - Types of contract quality requirements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... CONTRACT MANAGEMENT QUALITY ASSURANCE Contract Quality Requirements 46.202 Types of contract quality requirements. Contract quality requirements fall into four general categories, depending on the extent of... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Types of contract quality...

  3. Department of Defense Prime Contract Awards by Service Category and Federal Supply Classification, Fiscal Years 1979, 1980, 1981, 1982

    DTIC Science & Technology

    1982-01-01

    7630 RECREATIONAL AND GYMNASTIC EQUIPMENT 1,409 2.773 2,894 3,936 TOTAL 2, 71 4,552 8,0o3 8,292 76 CLEANRINO ECUIPIENT AND SUPPL IES 7910 FLOOR POLISHERS...OOPES VARNISHES AND RELATED PROD 4,715 .6.51 9,394 10.453 SOS0 PAINT AND ARTISTS BRUSHES - 27 10 67 11 6030 PRESERVATIVE AND SEALING COMPOUNDS 9,003

  4. Prime Contract Awards by Service Category and Federal Supply Classification, Fiscal Years 1980, 1981, 1982, 1983.

    DTIC Science & Technology

    1983-01-01

    GYMNASTIC EQUIPMENT 1,773 2 e94 3,938 2 49P TOTAL 4,552 5,038 8 292 5 278 79 CLEANING EQUIPMENT AND SUPPLIES 7910 FLOOR POLISHERS AND VACUUM CLEANERS 1,188...8020 PAINT AND ARTISTS BRUSHES 10 67 11 0 8030 PRESERVATIVE AND SEALING COMPOUNDS 851 8.340 2.169 1.183 8040 ADHESIVES 272 447 839 278 TOTAL 7.288 18,248

  5. Piston rod seal

    DOEpatents

    Lindskoug, Stefan

    1984-01-01

    In a piston rod seal of the type comprising a gland through which the piston rod is passed the piston is provided with a sleeve surrounding the piston rod and extending axially so as to axially partly overlap the gland when the piston is in its bottom dead center position.

  6. GROUTING TECHNIQUES IN BOTTOM SEALING OF HAZARDOUS WASTE SITES

    EPA Science Inventory

    Bottom sealing of hazardous waste sites involves the injection or insertion of an inert impermeable and continuous horizontal barrier in soil below the source of contamination. This type of containment strategy could be used in conjunction with other technology such as slurry wal...

  7. Two piston V-type Stirling engine

    DOEpatents

    Corey, John A.

    1987-01-01

    A two piston Stirling engine which includes a heat exchanger arrangement placing the cooler and regenerator directly adjacent the compression space for minimal cold duct volume; a sealing arrangement which eliminates the need for piston seals, crossheads and piston rods; and a simplified power control system.

  8. Preliminary investigation of a possible lung worm (Parafilaroides decorus), fish (Girella nigricans), and marine mammal (Callorhinus ursinus) cycle for San Miguel sea lion virus type 5.

    PubMed

    Smith, A W; Skilling, D E; Brown, R J

    1980-11-01

    Colostrum-deprived neonatal Northern fur seal pups (Callorhinus ursinus) were exposed to San Miguel sea lion virus type 5 (SMSV-5) by feeding them fish (Girella nigricans) infected with virus or fish infected with both the sea lion lung worm larvae (Parafilaroides decorus) and virus. Virus infection was demonstrated in 8 of 9 pups, and 1 of these developed a vesicular lesion on the flipper. In this sequence, P decorus larvae exposed to SMSV-5 were fed to G nigricans held at 15 C in a salt water aquarium; 32 days later, these fish were killed, then fed to the fur seal pups. The vesicle developed 22 days subsequent to this and SMSV-5 was reisolated from the lesion. The SMSV-5 was shown to persist for at least 23 days in infected neonatal fur seals. Attempts to establish P decorus infection in Northern fur seal pups were apparently unsuccessful.

  9. Reliability evaluation of hermetic dual in-line flat microcircuit packages

    NASA Technical Reports Server (NTRS)

    Johnson, G. M.; Conaway, L. K.

    1977-01-01

    The relative strengths and weaknesses of 35 commonly used hermetic flat and dual in-line packages were determined and used to rank each of the packages according to a numerical weighting scheme for package attributes. The list of attributes included desirable features in five major areas: lead and lead seal, body construction, body materials, lid and lid seal, and marking. The metal flat pack and multilayer integral ceramic flat pack and DIP received the highest rankings, and the soft glass Cerdip and Cerpak types received the lowest rankings. Loss of package hermeticity due to lead and lid seal problems was found to be the predominant failure mode from the literature/data search. However, environmental test results showed that lead and lid seal failures due to thermal stressing was only a problem with the hard glass (Ceramic) body DIP utilizing a metal lid and/or bottom. Insufficient failure data were generated for the other package types tested to correlate test results with the package ranking.

  10. Computerized X-ray Microtomography Observations and Fluid Flow Measurements of the Effect of Effective Stress on Fractured Reservoir Seal Shale

    NASA Astrophysics Data System (ADS)

    Welch, N.; Crawshaw, J.; Boek, E.

    2014-12-01

    The successful storage of carbon dioxide in geologic formations requires an in-depth understanding of all reservoir characteristics and morphologies. An intact and substantial seal formation above a storage reservoir is required for a significant portion of the initial sealing mechanisms believed to occur during carbon dioxide storage operations. Shales are a common seal formation rock types found above numerous hydrocarbon reservoirs, as well as potential saline aquifer storage locations. Shales commonly have very low permeability, however they also have the tendency to be quite fissile, and the formation of fractures within these seals can have a significant detrimental effect on the sealing potential of a reservoir and amount to large areas of high permeability and low capillary pressures compared to the surrounding intact rock. Fractured shales also have an increased current interest due to the increasing development of shale gas reservoirs using hydraulic fracturing techniques. This work shows the observed changes that occur within fractured pieces of reservoir seal shale samples, along with quarry analogues, using an in-situ micro-CT fluid flow imaging apparatus with a Hassler type core holder. Changes within the preferential flow path under different stress regimes as well as physical changes to the fracture geometry are reported. Lattice Boltzmann flow simulations were then performed on the extracted flow paths and compared to experiment permeability measurements. The preferential flow path of carbon dioxide through the fracture network is also observed and compared to the results two-phase Lattice Boltzmann fluid flow simulations.

  11. 48 CFR 246.202 - Types of contract quality requirements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... SYSTEM, DEPARTMENT OF DEFENSE CONTRACT MANAGEMENT QUALITY ASSURANCE Contract Quality Requirements 246.202 Types of contract quality requirements. ... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Types of contract quality...

  12. The Pharmaceutical Capping Process-Correlation between Residual Seal Force, Torque Moment, and Flip-off Removal Force.

    PubMed

    Mathaes, Roman; Mahler, Hanns-Christian; Vorgrimler, Lothar; Steinberg, Henrik; Dreher, Sascha; Roggo, Yves; Nieto, Alejandra; Brown, Helen; Roehl, Holger; Adler, Michael; Luemkemann, Joerg; Huwyler, Joerg; Lam, Philippe; Stauch, Oliver; Mohl, Silke; Streubel, Alexander

    2016-01-01

    The majority of parenteral drug products are manufactured in glass vials with an elastomeric rubber stopper and a crimp cap. The vial sealing process is a critical process step during fill-and-finish operations, as it defines the seal quality of the final product. Different critical capping process parameters can affect rubber stopper defects, rubber stopper compression, container closure integrity, and also crimp cap quality. A sufficiently high force to remove the flip-off button prior to usage is required to ensure quality of the drug product unit by the flip-off button during storage, transportation, and until opening and use. Therefore, the final product is 100% visually inspected for lose or defective crimp caps, which is subjective as well as time- and labor-intensive. In this study, we sealed several container closure system configurations with different capping equipment settings (with corresponding residual seal force values) to investigate the torque moment required to turn the crimp cap. A correlation between torque moment and residual seal force has been established. The torque moment was found to be influenced by several parameters, including diameter of the vial head, type of rubber stopper (serum or lyophilized) and type of crimp cap (West(®) or Datwyler(®)). In addition, we measured the force required to remove the flip-off button of a sealed container closure system. The capping process had no influence on measured forces; however, it was possible to detect partially crimped vials. In conclusion, a controlled capping process with a defined target residual seal force range leads to a tight crimp cap on a sealed container closure system and can ensure product quality. The majority of parenteral drug products are manufactured in a glass vials with an elastomeric rubber stopper and a crimp cap. The vial sealing process is a critical process step during fill-and-finish operations, as it defines the seal quality of the final product. An adequate force to remove the flip-off button prior to usage is required to ensure product quality during storage and transportation until use. In addition, the complete crimp cap needs to be fixed in a tight position on the vial. In this study, we investigated the torque moment required to turn the crimp cap and the force required to remove the flip-off button of container closure system sealed with different capping equipment process parameters (having different residual seal force values). © PDA, Inc. 2016.

  13. GOLD PRESSURE VESSEL SEAL

    DOEpatents

    Smith, A.E.

    1963-11-26

    An improved seal between the piston and die member of a piston-cylinder type pressure vessel is presented. A layer of gold, of sufficient thickness to provide an interference fit between the piston and die member, is plated on the contacting surface of at least one of the members. (AEC)

  14. 48 CFR 16.102 - Policies.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 1 2013-10-01 2013-10-01 false Policies. 16.102 Section 16.102 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION CONTRACTING METHODS AND CONTRACT TYPES TYPES OF CONTRACTS Selecting Contract Types 16.102 Policies. (a) Contracts resulting from...

  15. 41 CFR 302-12.103 - May we separately contract for each type of relocation service?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... contract for each type of relocation service? 302-12.103 Section 302-12.103 Public Contracts and Property... A RELOCATION SERVICES COMPANY Agency's Use of a Relocation Services Company § 302-12.103 May we separately contract for each type of relocation service? Yes, you may separately contract for each type of...

  16. 48 CFR 1516.303-73 - Types of cost-sharing.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ..., cost matching, or other in-kind contributions. (b) In-kind contributions represent non-cash... 48 Federal Acquisition Regulations System 6 2010-10-01 2010-10-01 true Types of cost-sharing. 1516... CONTRACTING METHODS AND CONTRACT TYPES TYPES OF CONTRACTS Cost-Reimbursement Contracts 1516.303-73 Types of...

  17. Enhanced simulation software for rocket turbopump, turbulent, annular liquid seals

    NASA Technical Reports Server (NTRS)

    Padavala, Satya; Palazzolo, Alan

    1994-01-01

    One of the main objectives of this work is to develop a new dynamic analysis for liquid annular seals with arbitrary profile and to analyze a general distorted interstage seal of the space shuttle main engine high pressure oxygen turbopump (SSME-ATD-HPOTP). The dynamic analysis developed is based on a method originally proposed by Nelson and Nguyen. A simpler scheme based on cubic splines is found to be computationally more efficient and has better convergence properties at higher eccentricities. The first order solution of the original analysis is modified by including a more exact solution that takes into account the variation of perturbed variables along the circumference. A new set of equations for dynamic analysis are derived based on this more general model. A unified solution procedure that is valid for both Moody's and Hirs' friction models is presented. Dynamic analysis is developed for three different models: constant properties, variable properties, and thermal effects with variable properties. Arbitrarily varying seal profiles in both axial and circumferential directions are considered. An example case of an elliptical seal with varying degrees of axial curvature is analyzed in detail. A case study based on predicted clearances of an interstage seal of the SSME-ATD-HPOTP is presented. Dynamic coefficients based on external specified load are introduced to analyze seals that support a preload. The other objective of this work is to study the effect of large rotor displacements of SSME-ATD-HPOTP on the dynamics of the annular seal and the resulting transient motion. One task is to identify the magnitude of motion of the rotor about the centered position and establish limits of effectiveness of using current linear models. This task is accomplished by solving the bulk flow model seal governing equations directly for transient seal forces for any given type of motion, including motion with large eccentricities. Based on the above study, an equivalence is established between linearized coefficients based transient motion and the same motion as predicted by the original governing equations. An innovative method is developed to model nonlinearities in an annular seal based on dynamic coefficients computed at various static eccentricities. This method is thoroughly tested for various types of transient motion using bulk flow model results as a benchmark.

  18. Poppet valve tester

    NASA Technical Reports Server (NTRS)

    Tellier, G. F.

    1973-01-01

    Tester investigates fundamental factors affecting cyclic life and sealing performance of valve seats and poppets. Tester provides for varying impact loading of poppet against seat and rate of cycling, and controls amount and type of relative motion between sealing faces of seat and poppet. Relative motion between seat and poppet can be varied in three modes.

  19. Multi-Scale Transport Properties of Fine-Grained Rocks: A Case Study of the Kirtland Formation, San Juan Basin, USA

    NASA Astrophysics Data System (ADS)

    Heath, J. E.; Dewers, T. A.; McPherson, B. J.; Wilson, T. H.; Flach, T.

    2009-12-01

    Understanding and characterizing transport properties of fine-grained rocks is critical in development of shale gas plays or assessing retention of CO2 at geologic storage sites. Difficulties arise in that both small scale (i.e., ~ nm) properties of the rock matrix and much larger scale fractures, faults, and sedimentological architecture govern migration of multiphase fluids. We present a multi-scale investigation of sealing and transport properties of the Kirtland Formation, which is a regional aquitard and reservoir seal in the San Juan Basin, USA. Sub-micron dual FIB/SEM imaging and reconstruction of 3D pore networks in core samples reveal a variety of pore types, including slit-shaped pores that are co-located with sedimentary structures and variations in mineralogy. Micron-scale chemical analysis and XRD reveal a mixture of mixed-layer smectite/illite, chlorite, quartz, and feldspar with little organic matter. Analysis of sub-micron digital reconstructions, mercury capillary injection pressure, and gas breakthrough measurements indicate a high quality sealing matrix. Natural full and partially mineralized fractures observed in core and in FMI logs include those formed from early soil-forming processes, differential compaction, and tectonic events. The potential impact of both fracture and matrix properties on large-scale transport is investigated through an analysis of natural helium from core samples, 3D seismic data and poro-elastic modeling. While seismic interpretations suggest considerable fracturing of the Kirtland, large continuous fracture zones and faults extending through the seal to the surface cannot be inferred from the data. Observed Kirtland Formation multi-scale transport properties are included as part of a risk assessment methodology for CO2 storage. Acknowledgements: The authors gratefully acknowledge the U.S. Department of Energy’s (DOE) National Energy Technology Laboratory for sponsoring this project. The DOE’s Basic Energy Science Office funded the dual FIB/SEM analysis. The Kirtland Formation overlies the coal seams of the Fruitland into which CO2 has been injected as a Phase II demonstration of the Southwest Regional Partnership on Carbon Sequestration. Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the U.S. Department of Energy under contract DE-ACOC4-94AL85000.

  20. Diverter assembly for radioactive material

    DOEpatents

    Andrews, Katherine M.; Starenchak, Robert W.

    1989-01-01

    A diverter assembly for diverting a pneumatically conveyed holder for a radioactive material between a central conveying tube and one of a plurality of radially offset conveying tubes includes an airtight container. A diverter tube having an offset end is suitably mounted in the container for rotation. A rotary seal seals one end of the diverter tube during and after rotation of the diverter tube while a spring biased seal seals the other end of the diverter tube which mvoes between various offset conveying tubes. An indexing device rotatably indexes the diverter tube and this indexing device is driven by a suitable drive. The indexing mechanism is preferably a geneva-type mechanism to provide a locking of the diverter tube in place.

  1. Space shuttle prototype check valve development

    NASA Technical Reports Server (NTRS)

    Tellier, G. F.

    1976-01-01

    Contaminant-resistant seal designs and a dynamically stable prototype check valve for the orbital maneuvering and reaction control helium pressurization systems of the space shuttle were developed. Polymer and carbide seal models were designed and tested. Perfluoroelastomers compatible with N2O4 and N2H4 types were evaluated and compared with Teflon in flat and captive seal models. Low load sealing and contamination resistance tests demonstrated cutter seal superiority over polymer seals. Ceramic and carbide materials were evaluated for N2O4 service using exposure to RFNA as a worst case screen; chemically vapor deposited tungsten carbide was shown to be impervious to the acid after 6 months immersion. A unique carbide shell poppet/cutter seat check valve was designed and tested to demonstrate low cracking pressure ( 2.0 psid), dynamic stability under all test bench flow conditions, contamination resistance (0.001 inch CRES wires cut with 1.5 pound seat load) and long life of 100,000 cycles (leakage 1.0 scc/hr helium from 0.1 to 400 psig).

  2. 48 CFR 3416.307 - Contract clauses.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 7 2010-10-01 2010-10-01 false Contract clauses. 3416.307 Section 3416.307 Federal Acquisition Regulations System DEPARTMENT OF EDUCATION ACQUISITION REGULATION CONTRACTING METHODS AND CONTRACT TYPES TYPES OF CONTRACTS Cost-Reimbursement Contracts 3416.307 Contract...

  3. Psychological contract types as moderator in the breach-violation and violation-burnout relationships.

    PubMed

    Jamil, Amber; Raja, Usman; Darr, Wendy

    2013-01-01

    This research examined the relationships between perceived psychological contract breach, felt violation, and burnout in a sample (n = 361) of employees from various organizations in Pakistan. The moderating role of contract types in these relationships was also tested. Findings supported a positive association between perceived psychological contract breach and felt violation and both were positively related to burnout. Transactional and relational contracts moderated the felt violation-burnout relationship. Scores on relational contract type tended to be higher than for transactional contract type showing some contextual influence.

  4. Effects of Polypropylene Orientation on Mechanical and Heat Seal Properties of Polymer-Aluminum-Polymer Composite Films for Pouch Lithium-Ion Batteries.

    PubMed

    Zeng, Fangxinyu; Chen, Jinyao; Yang, Feng; Kang, Jian; Cao, Ya; Xiang, Ming

    2018-01-16

    In this study, polyamide-aluminum foil-polypropylene (PA-Al-PP) composite films with different orientation status of the PP layer were prepared, and their morphology, tensile, peeling and heat seal behavior were studied. The comparative study of tensile and fracture behaviors of single-layer film of PA, Al and PP, as well as the composite films of PA-Al, PP-Al and PA-Al-PP revealed that in PA-Al-PP composite film, the PA layer with the highest tensile strength can share the tensile stress from the Al layer during stretching, while the PP layer with the lowest tensile strength can prevent further development of the small cracks on boundary of the Al layer during stretching. Moreover, the study of heat seal behavior suggested that both the orientation status and the heat seal conditions were important factors in determining the heat seal strength ( HSS ) and failure behavior of the sample. Four failure types were observed, and a clear correspondence between HSS and failure types was found. The results also elucidated that for the composite film, only in the cases where the tensile stress was efficiently released by each layer during HSS measurement could the composite film exhibit desired high HSS that was even higher than its tensile strength.

  5. Underwater noise from three types of offshore wind turbines: estimation of impact zones for harbor porpoises and harbor seals.

    PubMed

    Tougaard, Jakob; Henriksen, Oluf Damsgaard; Miller, Lee A

    2009-06-01

    Underwater noise was recorded from three different types of wind turbines in Denmark and Sweden (Middelgrunden, Vindeby, and Bockstigen-Valar) during normal operation. Wind turbine noise was only measurable above ambient noise at frequencies below 500 Hz. Total sound pressure level was in the range 109-127 dB re 1 microPa rms, measured at distances between 14 and 20 m from the foundations. The 1/3-octave noise levels were compared with audiograms of harbor seals and harbor porpoises. Maximum 1/3-octave levels were in the range 106-126 dB re 1 microPa rms. Maximum range of audibility was estimated under two extreme assumptions on transmission loss (3 and 9 dB per doubling of distance, respectively). Audibility was low for harbor porpoises extending 20-70 m from the foundation, whereas audibility for harbor seals ranged from less than 100 m to several kilometers. Behavioral reactions of porpoises to the noise appear unlikely except if they are very close to the foundations. However, behavioral reactions from seals cannot be excluded up to distances of a few hundred meters. It is unlikely that the noise reaches dangerous levels at any distance from the turbines and the noise is considered incapable of masking acoustic communication by seals and porpoises.

  6. Thin-film sulfuric acid anodizing as a replacement for chromic acid anodizing

    NASA Technical Reports Server (NTRS)

    Kallenborn, K. J.; Emmons, J. R.

    1995-01-01

    Chromic acid has long been used to produce a thin, corrosion resistant (Type I) coating on aluminum. Following anodizing, the hardware was sealed using a sodium dichromate solution. Sealing closes up pores inherent in the anodized coating, thus improving corrosion resistance. The thinness of the brittle coating is desirable from a fatigue standpoint, and chromium was absorbed by the coating during the sealing process, further improving corrosion resistance. Unfortunately, both chromic acid and sodium dichromate contain carcinogenic hexavalent chromium. Sulfuric acid is being considered as a replacement for chromic acid. Sulfuric acid of 10-20 percent concentration has traditionally been used to produce relatively thick (Types II and III) or abrasion resistant (Type III) coatings. A more dilute, that is five weight percent, sulfuric acid anodizing process, which produces a thinner coating than Type II or III, with nickel acetate as the sealant has been developed. The process was evaluated in regard to corrosion resistance, throwing power, fatigue life, and processing variable sensitivity, and shows promise as a replacement for the chromic acid process.

  7. 48 CFR 1316.602 - Labor-hour contracts.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Labor-hour contracts. 1316... AND CONTRACT TYPES TYPES OF CONTRACTS Time-and-Materials, Labor-Hour, and Letter Contracts 1316.602 Labor-hour contracts. ...

  8. 48 CFR 16.405-1 - Cost-plus-incentive-fee contracts.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Cost-plus-incentive-fee... CONTRACTING METHODS AND CONTRACT TYPES TYPES OF CONTRACTS Incentive Contracts 16.405-1 Cost-plus-incentive-fee contracts. (a) Description. The cost-plus-incentive-fee contract is a cost-reimbursement contract that...

  9. 48 CFR 716.406 - Contract clauses.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 5 2011-10-01 2011-10-01 false Contract clauses. 716.406 Section 716.406 Federal Acquisition Regulations System AGENCY FOR INTERNATIONAL DEVELOPMENT CONTRACTING METHODS AND CONTRACT TYPES TYPES OF CONTRACTS Cost Reimbursement Contracts 716.406 Contract clauses. The...

  10. 48 CFR 716.406 - Contract clauses.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Contract clauses. 716.406 Section 716.406 Federal Acquisition Regulations System AGENCY FOR INTERNATIONAL DEVELOPMENT CONTRACTING METHODS AND CONTRACT TYPES TYPES OF CONTRACTS Cost Reimbursement Contracts 716.406 Contract clauses. The...

  11. 48 CFR 3416.701 - Contract clause.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 7 2010-10-01 2010-10-01 false Contract clause. 3416.701 Section 3416.701 Federal Acquisition Regulations System DEPARTMENT OF EDUCATION ACQUISITION REGULATION CONTRACTING METHODS AND CONTRACT TYPES TYPES OF CONTRACTS Agreements 3416.701 Contract clause. The contracting...

  12. Detection of seal contamination in heat-sealed food packaging based on active infrared thermography

    NASA Astrophysics Data System (ADS)

    D'huys, Karlien; Saeys, Wouter; De Ketelaere, Bart

    2015-05-01

    In the food industry packaging is often applied to protect the product from the environment, assuring quality and safety throughout shelf life if properly performed. Packaging quality depends on the material used and the closure (seal). The material is selected based on the specific needs of the food product to be wrapped. However, proper closure of the package is often harder to achieve. One problem possibly jeopardizing seal quality is the presence of food particles between the seal. Seal contamination can cause a decreased seal strength and thus an increased packaging failure risk. It can also trigger the formation of microchannels through which air and microorganisms can enter and spoil the enclosed food. Therefore, early detection and removal of seal-contaminated packages from the production chain is essential. In this work, a pulsed-type active thermography method using the heat of the sealing bars as an excitation source was studied for detecting seal contamination. The cooling profile of contaminated seals was recorded. The detection performance of four processing methods (based on a single frame, a fit of the cooling profile, pulsed phase thermography and a matched filter) was compared. High resolution digital images served as a reference to quantify contamination. The lowest detection limit (equivalent diameter of 0.63 mm) and the lowest processing time (0.42 s per sample) were obtained for the method based on a single frame. Presumably, practical limitations in the recording stage prevented the added value of active thermography to be fully reflected in this application.

  13. Stationary spiraling eddies in presence of polar amplification of global warming as a governing factor of ecology of Greenland seals White Sea population: results of verification study

    NASA Astrophysics Data System (ADS)

    Melentyev, K.; Chernook, V.; Melentyev, V.

    2003-04-01

    Ice-associated forms of marine mammals are representatives of a high level of fodder chains in the ocean and taxation of population number for different group, as assessment of ecology and animal welfare are the important tasks for marine biology, ecology, fishery and other application uses. Many problems create a global warming and antropogenical impact on marine and coastal ecosystem. In order to investigate ice covered Arctic Ocean and charting the number of seals were performed annual inspections onboard research aircraft PINRO "Arktika". Multi-spectral airborne and satellite observations were fulfilled regularly from Barents and White Sea to the Bering and Okhotsk Sea (1996-2002). A contemporary status of different group of sea mammals was evaluated, where number of adults and pups were checked separately. In situ observations were provided with using helicopter and icebreaker for gathering a water samples and ice cores (with following biochemical and toxicological analysis). A prevailing part of life cycle of Greenland seals (harp seal) is strongly depended from winter hydrology (water masses, stable currents, meandering fronts, stationary eddies) and closely connected with type of ice (pack, fast ice) and other parameters of ice (age, origin, salinity, ice edge.). First-year ice floes which has a specific properties and distinctive features are used by harp seals for pupping, lactation, molting, pairing and resting. Ringed seals, inversely, use for corresponding purposes only fast-ice. Different aspects of ecology, and migration features of harp seals were analyzed in frame of verification study. It was revealed a scale of influence of winter severity and wind regime, but stationary eddies in the White Sea is most effective governing factor (novelty). Following relationship " eddies - ecology of Greenland seal White Sea population " will be discussed: A) regularities of eddies formation and their spatial arrangement, temporal (seasonal and annual) modification; B) eddies displacement and parameters modification (type of eddy, intensity and sign of rotation) as result of climate change; C) relationship between eddies location and whelping rookeries arrangement, climate change and variety of the type of migration; D) stationary eddy as zone of concentration of polluted waters and toxically hazard, climate change and self-cleaning ability; E) spiraling eddies in changing climate and prediction of modification of marine animal welfare.

  14. Hydrodynamic detection and localization of artificial flatfish breathing currents by harbour seals (Phoca vitulina).

    PubMed

    Niesterok, Benedikt; Krüger, Yvonne; Wieskotten, Sven; Dehnhardt, Guido; Hanke, Wolf

    2017-01-15

    Harbour seals are known to be opportunistic feeders, whose diet consists mainly of pelagic and benthic fish, such as flatfish. As flatfish are often cryptic and do not produce noise, we hypothesized that harbour seals are able to detect and localize flatfish using their hydrodynamic sensory system (vibrissae), as fish emit water currents through their gill openings (breathing currents). To test this hypothesis, we created an experimental platform where an artificial breathing current was emitted through one of eight different openings. Three seals were trained to search for the active opening and station there for 5 s. Half of the trials were conducted with the seal blindfolded with an eye mask. In blindfolded and non-blindfolded trials, all seals performed significantly better than chance. The seals crossed the artificial breathing current (being emitted into the water column at an angle of 45 deg to the ground) from different directions. There was no difference in performance when the seals approached from in front, from behind or from the side. All seals responded to the artificial breathing currents by directly moving their snout towards the opening from which the hydrodynamic stimulus was emitted. Thus, they were also able to extract directional information from the hydrodynamic stimulus. Hydrodynamic background noise and the swimming speed of the seals were also considered in this study as these are aggravating factors that seals in the wild have to face during foraging. By creating near-natural conditions, we show that harbour seals have the ability to detect a so-far overlooked type of stimulus. © 2017. Published by The Company of Biologists Ltd.

  15. 48 CFR 216.504 - Indefinite-quantity contracts.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Deputy Director, Defense Procurement and Acquisition Policy (Contract Policy and International... contracts. 216.504 Section 216.504 Federal Acquisition Regulations System DEFENSE ACQUISITION REGULATIONS SYSTEM, DEPARTMENT OF DEFENSE CONTRACTING METHODS AND CONTRACT TYPES TYPES OF CONTRACTS Indefinite...

  16. Steam Turbine Flow Path Seals (a Review)

    NASA Astrophysics Data System (ADS)

    Neuimin, V. M.

    2018-03-01

    Various types of shroud, diaphragm, and end seals preventing idle leak of working steam are installed in the flow paths of steam turbine cylinders for improving their efficiency. Widely known labyrinth seals are most extensively used in the Russian turbine construction industry. The category of labyrinth seals also includes seals with honeycomb inserts. The developers of seals with honeycomb inserts state that the use of such seals makes it possible to achieve certain gain due to smaller leaks of working fluid and more reliable operation of the system under the conditions in which the rotor rotating parts may rub against the stator elements. However, a positive effect can only be achieved if the optimal design parameters of the honeycomb structure are fulfilled with due regard to the specific features of its manufacturing technology and provided that this structure is applied in a goal-seeking manner in the seals of steam and gas turbines and compressors without degrading their vibration stability. Calculated and preliminary assessments made by experts testify that the replacement of conventional labyrinth seals by seals with honeycomb inserts alone, due to which the radial gaps in the shroud seal can be decreased from 1.5 to 0.5 mm, allows the turbine cylinder efficiency to be increased at the initial stage by approximately 1% with the corresponding gain in the turbine set power output. The use of rectangular-cellular seals may result, according to estimates made by their developers, in a further improvement of turbine efficiency by 0.5-1.0%. The labor input required to fabricate such seals is six to eight times smaller than that to fabricate labyrinth seals with honeycomb inserts. Recent years have seen the turbine construction companies of the United States and Germany advertising the use of abradable (sealing) coatings (borrowed from the gas turbine construction technology) in the turbine designs instead of labyrinth seals. The most efficient performance of such seals in the turbine flow path is achieved with the sealing material-to-blade linear wear ratio equal to 10 : 1. According to estimates of the developers, application of abradable (sealing) coatings to all problem surfaces (resulting in the power output increased by 0.5-1.0%) is economically profitable even if this procedure is carried out under field conditions at a thermal power plant.

  17. 40 CFR 146.12 - Construction requirements.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... water. The casing and cement used in the construction of each newly drilled well shall be designed for... intervals; and (7) Type or grade of cement. (c) All Class I injection wells, except those municipal wells... injection zone, or tubing with an approved fluid seal as an alternative. The tubing, packer, and fluid seal...

  18. 40 CFR 63.564 - Monitoring requirements.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... all times when the car seals have been broken and the valve position has been changed. Each by-pass line valve shall be secured in the closed position with a car-seal or a lock-and-key type configuration... for this purpose). (e) Combustion device, except flare. For sources complying with § 63.563(b)(4), use...

  19. 40 CFR 63.564 - Monitoring requirements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... all times when the car seals have been broken and the valve position has been changed. Each by-pass line valve shall be secured in the closed position with a car-seal or a lock-and-key type configuration... for this purpose). (e) Combustion device, except flare. For sources complying with § 63.563(b)(4), use...

  20. 40 CFR 63.148 - Leak inspection provisions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Standards for Organic Hazardous Air Pollutants From the Synthetic Organic Chemical Manufacturing Industry... line; or (2) Secure the bypass line valve in the closed position with a car-seal or a lock-and-key type... configuration has been checked out, and records of any car-seal that has broken. (4) For each inspection during...

  1. 40 CFR 63.148 - Leak inspection provisions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Standards for Organic Hazardous Air Pollutants From the Synthetic Organic Chemical Manufacturing Industry... line; or (2) Secure the bypass line valve in the closed position with a car-seal or a lock-and-key type... configuration has been checked out, and records of any car-seal that has broken. (4) For each inspection during...

  2. 40 CFR 63.148 - Leak inspection provisions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Standards for Organic Hazardous Air Pollutants From the Synthetic Organic Chemical Manufacturing Industry... line; or (2) Secure the bypass line valve in the closed position with a car-seal or a lock-and-key type... configuration has been checked out, and records of any car-seal that has broken. (4) For each inspection during...

  3. 40 CFR 63.148 - Leak inspection provisions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Standards for Organic Hazardous Air Pollutants From the Synthetic Organic Chemical Manufacturing Industry... line; or (2) Secure the bypass line valve in the closed position with a car-seal or a lock-and-key type... configuration has been checked out, and records of any car-seal that has broken. (4) For each inspection during...

  4. 48 CFR 1516.405-2 - Cost-plus-award-fee contracts.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 6 2010-10-01 2010-10-01 true Cost-plus-award-fee... AGENCY CONTRACTING METHODS AND CONTRACT TYPES TYPES OF CONTRACTS Incentive Contracts 1516.405-2 Cost-plus-award-fee contracts. ...

  5. Influence of different types of seals on the stability behavior of turbopumps

    NASA Technical Reports Server (NTRS)

    Diewald, W.; Nordmann, R.

    1989-01-01

    One of the main problems in designing a centrifugal pump is to achieve a good efficiency while not neglecting the dynamic performance of the machine. The first aspect leads to the design of grooved seals in order to minimize the leakage flow. But the influence of these grooves to the dynamic behavior is not well known. Experimental and theoretical results of the rotordynamic coefficients for different groove shapes and depths in seals is presented. In addition, the coefficients are applied to a simple pump model.

  6. Effect on moisture permeability of typewriting on unit dose package surfaces.

    PubMed

    Rackson, J T; Zellhofer, M J; Birmingham, P H

    1984-10-01

    The effects of typewriting on labels of two unit dose packages with respect to moisture permeability were examined. Using an electric typewriter, a standard label format was imprinted on two different types of class A unit dose packages: (1) a heat-sealed paper-backed foil and cellofilm strip pouch, and (2) a copolyester and polyethylene multiple-cup blister with a heat-sealed paper-backed foil and cellofilm cover. The labels were typed at various typing-element impact settings. The official USP test for water permeation was then performed on typed packages and untyped control packages. The original untyped packages were confirmed to be USP class A quality. The packages for which successively harder impact settings were used showed a corresponding increase in moisture permeability. This resulted in a lowering of USP package ratings from class A to class B and D, some of which would be unsuitable for use in any unit dose system under current FDA repackaging standards. Typing directly onto the label of a unit dose package before it is sealed will most likely damage the package and possibly make it unfit for use. Pharmacists who must type labels for the unit dose packages studied should use the lowest possible typewriter impact setting and test for damage using the USP moisture-permeation test.

  7. Impact of Micro-to Meso-scale Fractures on Sealing Behavior of Argillaceous Cap Rocks For CO 2 Sequestration

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

    Evans, James

    This multi-disciplinary project evaluated seal lithologies for the safety and security of long-term geosequestration of CO 2. We used integrated studies to provide qualitative risk for potential seal failure; we integrated data sets from outcrop, core, geochemical analysis, rock failure properties from mechanical testing, geophysical wireline log analysis, and geomechanical modeling to understand the effects of lithologic heterogeneity and changing mechanical properties have on the mechanical properties of the seal. The objectives of this study were to characterize cap rock seals using natural field analogs, available drillhole logging data and whole-rock core, geochemical and isotopic analyses. Rock deformation experiments weremore » carried out on collected samples to develop better models of risk estimation for potential cap rock seal failure. We also sampled variably faulted and fractured cap rocks to examine the impacts of mineralization and/or alteration on the mechanical properties. We compared CO 2 reacted systems to non-CO 2 reacted seal rock types to determine response of each to increased pore fluid pressures and potential for the creation of unintentional hydrofractures at depth.« less

  8. Contracting and Higher Education.

    ERIC Educational Resources Information Center

    Ferris, James M.

    1991-01-01

    The potential gains in efficiency of three types of contracts in college administration are contrasted. Contract types include explicit contracts in the budgeting process between the state and higher education institutions; institutional contracting for inputs; and interinstitutional contracting. The tradeoff between production cost savings and…

  9. 48 CFR 2816.602 - Labor-hour contracts.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 6 2010-10-01 2010-10-01 true Labor-hour contracts. 2816... and Contract Types TYPES OF CONTRACTS Time-and-Materials, Labor-Hour, and Letter Contracts 2816.602 Labor-hour contracts. The limitations set forth in 2816.601 for time-and-material contracts also apply...

  10. 48 CFR 16.602 - Labor-hour contracts.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Labor-hour contracts. 16... METHODS AND CONTRACT TYPES TYPES OF CONTRACTS Time-and-Materials, Labor-Hour, and Letter Contracts 16.602 Labor-hour contracts. Description. A labor-hour contract is a variation of the time-and-materials...

  11. 48 CFR 3016.170 - Contracts with Lead System Integrators.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 7 2012-10-01 2012-10-01 false Contracts with Lead System... Selecting Contract Types 3016.170 Contracts with Lead System Integrators. The contracting officer should... consulted to determine the appropriate contract type and fee structure for use in varied contracts with lead...

  12. 48 CFR 3016.170 - Contracts with Lead System Integrators.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 7 2013-10-01 2012-10-01 true Contracts with Lead System... Selecting Contract Types 3016.170 Contracts with Lead System Integrators. The contracting officer should... consulted to determine the appropriate contract type and fee structure for use in varied contracts with lead...

  13. 48 CFR 3016.170 - Contracts with Lead System Integrators.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 7 2014-10-01 2014-10-01 false Contracts with Lead System... Selecting Contract Types 3016.170 Contracts with Lead System Integrators. The contracting officer should... consulted to determine the appropriate contract type and fee structure for use in varied contracts with lead...

  14. 48 CFR 3016.170 - Contracts with Lead System Integrators.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 7 2011-10-01 2011-10-01 false Contracts with Lead System... Selecting Contract Types 3016.170 Contracts with Lead System Integrators. The contracting officer should... consulted to determine the appropriate contract type and fee structure for use in varied contracts with lead...

  15. 48 CFR 3016.170 - Contracts with Lead System Integrators.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 7 2010-10-01 2010-10-01 false Contracts with Lead System... Selecting Contract Types 3016.170 Contracts with Lead System Integrators. The contracting officer should... consulted to determine the appropriate contract type and fee structure for use in varied contracts with lead...

  16. Diverter assembly for radioactive material

    DOEpatents

    Andrews, K.M.; Starenchak, R.W.

    1988-04-11

    A diverter assembly for diverting a pneumatically conveyed holder for a radioactive material between a central conveying tube and one of a plurality of radially offset conveying tubes includes an airtight container. A diverter tube having an offset end is suitably mounted in the container for rotation. A rotary seal seals one end of the diverter tube during and after rotation of the diverter tube while a spring biased seal seals the other end of the diverter tube which moves between various offset conveying tubes. An indexing device rotatably indexes the diverter tube and this indexing device is driven by a suitable drive. The indexing mechanism is preferably a geneva-type mechanism to provide a locking of the diverter tube in place. 3 figs.

  17. Flip the tip: an automated, high quality, cost-effective patch clamp screen.

    PubMed

    Lepple-Wienhues, Albrecht; Ferlinz, Klaus; Seeger, Achim; Schäfer, Arvid

    2003-01-01

    The race for creating an automated patch clamp has begun. Here, we present a novel technology to produce true gigaseals and whole cell preparations at a high rate. Suspended cells are flushed toward the tip of glass micropipettes. Seal, whole-cell break-in, and pipette/liquid handling are fully automated. Extremely stable seals and access resistance guarantee high recording quality. Data obtained from different cell types sealed inside pipettes show long-term stability, voltage clamp and seal quality, as well as block by compounds in the pM range. A flexible array of independent electrode positions minimizes consumables consumption at maximal throughput. Pulled micropipettes guarantee a proven gigaseal substrate with ultra clean and smooth surface at low cost.

  18. Esophageal contractions in type 3 achalasia esophagus: simultaneous or peristaltic?

    PubMed

    Kim, Tae Ho; Patel, Nirali; Ledgerwood-Lee, Melissa; Mittal, Ravinder K

    2016-05-01

    Absence of peristalsis and impaired relaxation of lower esophageal sphincter are the hallmarks of achalasia esophagus. Based on the pressurization patterns, achalasia has been subdivided into three subtypes. The goal of our study was to evaluate the esophageal contraction pattern and bolus clearance in type 3 achalasia esophagus. High-resolution manometry (HRM) recordings of all patients diagnosed with achalasia esophagus in our center between the years 2011 and 2013 were reviewed. Recordings of 36 patients with type 3 achalasia were analyzed for the characteristics of swallow-induced "simultaneous esophageal contraction." The HRM impedance recordings of 14 additional patients with type 3 achalasia were analyzed for bolus clearance from the impedance recording. Finally, the HRM impedance along with intraluminal ultrasound imaging was conducted in six patients to further characterize the simultaneous esophageal contractions. Among 187 achalasia patients, 30 were type 1, 121 type 2, and 36 type 3. A total of 434 swallows evaluated in type 3 achalasia patients revealed that 95% of the swallow-induced contractions met criteria for simultaneous esophageal contraction, based on the onset of contraction. Interestingly, the peak and termination of the majority of simultaneous esophageal contractions were sequential. The HRM impedance revealed that 94% of the "simultaneous contractions" were associated with complete bolus clearance. Ultrasound image analysis revealed that baseline muscle thickness of patients in type 3 achalasia is larger than normal but the pattern of axial shortening is similar to that in normal subjects. The majority of esophageal contractions in type 3 achalasia are not true simultaneous contractions because the peak and termination of contraction are sequential and they are associated with complete bolus clearance.

  19. Concept designs of nonrotating-type centrifugal blood pump and basic study on output characteristics of the oscillating disk-type centrifugal pump.

    PubMed

    Kabei, N; Tuichiya, K; Sakurai, Y

    1994-09-01

    When designing a turbo-type blood pump as an artificial heart, the gap between a rotating shaft and a pump housing should be perfectly sealed to prevent any leakage or contamination through a seal. In addition, blood coagulation in a blood chamber must be avoided. To overcome these problems, we proposed five different nonrotating-type turbo pumps: a caudal-fin-type axial-flow pump, a caudal-fin-type centrifugal pump, a nutating-column-type centrifugal pump, a nutating-collapsible-tube-type centrifugal pump, and an oscillating-disk-type centrifugal pump. We selected and developed the oscillating-disk-type centrifugal pump that consists of a disk, a driving rod, a seal, an oscillation mechanism, and a pump housing. The disk is mounted on the end of the rod, which is connected to a high-speed DC motor through an oscillation mechanism. The rod and the disk do not rotate, but they oscillate in the pump housing. This movement of the disk generates forward fluid flow around the axis (i.e., the rotational fluid flow). Centrifugal force due to fluid rotation supports the pressure difference between the outlet and the inlet. The diameter of the disk is 39 mm, the maximum inner diameter of the pump housing is 40 mm, and the volume of the blood chamber for 25 degrees' oscillation is 16.9 ml. The performance of the pump was tested in a mock circulatory system.(ABSTRACT TRUNCATED AT 250 WORDS)

  20. 48 CFR 716.303 - Cost-sharing contracts.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Cost-sharing contracts. 716.303 Section 716.303 Federal Acquisition Regulations System AGENCY FOR INTERNATIONAL DEVELOPMENT CONTRACTING METHODS AND CONTRACT TYPES TYPES OF CONTRACTS Cost Reimbursement Contracts 716.303 Cost-sharing...

  1. 48 CFR 716.303 - Cost-sharing contracts.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 5 2011-10-01 2011-10-01 false Cost-sharing contracts. 716.303 Section 716.303 Federal Acquisition Regulations System AGENCY FOR INTERNATIONAL DEVELOPMENT CONTRACTING METHODS AND CONTRACT TYPES TYPES OF CONTRACTS Cost Reimbursement Contracts 716.303 Cost-sharing...

  2. 48 CFR 1316.405 - Cost-reimbursement incentive contracts.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Cost-reimbursement incentive contracts. 1316.405 Section 1316.405 Federal Acquisition Regulations System DEPARTMENT OF COMMERCE CONTRACTING METHODS AND CONTRACT TYPES TYPES OF CONTRACTS Incentive Contracts 1316.405 Cost-reimbursement...

  3. 48 CFR 916.405 - Cost-reimbursement incentive contracts.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Cost-reimbursement incentive contracts. 916.405 Section 916.405 Federal Acquisition Regulations System DEPARTMENT OF ENERGY CONTRACTING METHODS AND CONTRACT TYPES TYPES OF CONTRACTS Incentive Contracts 916.405 Cost-reimbursement...

  4. 48 CFR 3416.303 - Cost-sharing contracts.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 7 2010-10-01 2010-10-01 false Cost-sharing contracts. 3416.303 Section 3416.303 Federal Acquisition Regulations System DEPARTMENT OF EDUCATION ACQUISITION REGULATION CONTRACTING METHODS AND CONTRACT TYPES TYPES OF CONTRACTS Cost-Reimbursement Contracts 3416.303...

  5. Delidding and resealing hybrid microelectronic packages

    NASA Astrophysics Data System (ADS)

    Luce, W. F.

    1982-05-01

    The objective of this single phase MM and T contract was to develop the manufacturing technology necessary for the precision removal (delidding) and replacement (resealing) of covers on hermetically sealed hybrid microelectronic packages. The equipment and processes developed provide a rework technique which does not degrade the reliability of the package of the enclosed circuitry. A qualification test was conducted on 88 functional hybrid packages, with excellent results. A petition will be filed, accompanied by this report, requesting Mil-M-38510 be amended to allow this rework method.

  6. Improvements Needed on DoD Procurements from Robertson Fuel Systems (REDACTED)

    DTIC Science & Technology

    2015-06-25

    reasonable price, but is not certified. 4 A ballistically self-sealing tank is designed to prevent fuel loss and a fire after damage. FOR OFFICIAL USE ONLY...pubs/index.cfm. DoD IG DODIG-2015-120, “Defense Logistics Agency Did Not Obtain Fair and Reasonable Prices from Meggitt Aircraft Braking System for...Mobility Multipurpose Wheeled Vehicle Repair Parts,” April 4, 2014 DODIG-2014-020, “U.S. Army Contracting Command Did Not Obtain Fair and Reasonable

  7. Piping Connector

    NASA Technical Reports Server (NTRS)

    1994-01-01

    In Stennis Space Center's Component Test Facility, piping lines carry rocket propellants and high pressure cryogenic fuels. When the lines are chilled to a pretest temperature of 400 degrees below zero, ordinary piping connectors can leak. Under contract to Stennis, Reflange, Inc. developed the T-Con connector, which included a secondary seal that tolerates severe temperature change. Because of the limited need for the large and expensive T-Con product, Reflange also developed the less costly E-Con, a smaller more compact design with the same technical advantages as the T-Con.

  8. A Guide for the Perspective Navy Contractor

    DTIC Science & Technology

    1991-01-01

    11. FAR 52.214-26, Audit -Sealed Bidding (APR 1985) (Applicable if award exceeds $100,000) 12. FAR 52.214-27, Price Reduction for Defective Cost or...services in acca . -ce itih theter_ s and conditions. (3) For progress payzents, Goer-ent arowa! shall be deenedd to have occurred on the 5the working day...the event that an audit or other review of a specific financing request is required to ensure compliance with the terms and conditions of the contract

  9. Investigation of 14.5mm API Self-Sealing/Crashworthy Fuel Tank Material

    DTIC Science & Technology

    1974-09-01

    describes the results of a f-rogram for a crashworthy, 14.5mm API tolerant fuel cell construction developed and subjected co qualification testing. The...Paragraphs 4.6.6.4 and 4.6.6.5), which were not required by contract. Two fuel tanks were built of a construction designated by The Goodyear Tire & Rubber...TABLES 3 INTRODUCTION 4 FUEL TANK MATERIAL DESIGN STUDY (TASK I) 4 QUALIFIC/.TION OF CONSTRUCTION (TASK 11) ........ 5 FUEL TANK GUNFIRE 12

  10. Silicon-Based Anode and Method for Manufacturing the Same

    NASA Technical Reports Server (NTRS)

    Yushin, Gleb Nikolayevich (Inventor); Zdyrko, Bogdan (Inventor); Magasinski, Alexandre (Inventor); Luzinov, Igor (Inventor)

    2017-01-01

    A silicon-based anode comprising silicon, a carbon coating that coats the surface of the silicon, a polyvinyl acid that binds to at least a portion of the silicon, and vinylene carbonate that seals the interface between the silicon and the polyvinyl acid. Because of its properties, polyvinyl acid binders offer improved anode stability, tunable properties, and many other attractive attributes for silicon-based anodes, which enable the anode to withstand silicon cycles of expansion and contraction during charging and discharging.

  11. M2 and M3 muscarinic receptors are involved in enteric nerve-mediated contraction of the mouse ileum: Findings obtained with muscarinic-receptor knockout mouse.

    PubMed

    Takeuchi, Tadayoshi; Tanaka, Keisuke; Nakajima, Hidemitsu; Matsui, Minoru; Azuma, Yasu-Taka

    2007-01-01

    The involvement of muscarinic receptors in neurogenic responses of the ileum was studied in wild-type and muscarinic-receptor (M-receptor) knockout (KO) mice. Electrical field stimulation to the wild-type mouse ileum induced a biphasic response, a phasic and sustained contraction that was abolished by tetrodotoxin. The sustained contraction was prolonged for an extended period after the termination of electrical field stimulation. The phasic contraction was completely inhibited by atropine. In contrast, the sustained contraction was enhanced by atropine. Ileal strips prepared from M2-receptor KO mice exhibited a phasic contraction similar to that seen in wild-type mice and a sustained contraction that was larger than that in wild-type mice. In M3-receptor KO mice, the phasic contraction was smaller than that observed in wild-type mice. Acetylcholine exogenously administrated induced concentration-dependent contractions in strips isolated from wild-type, M2- and M3-receptor KO mice. However, contractions in M3-receptor KO mice shifted to the right. The sustained contraction was inhibited by capsaicin and neurokinin NK2 receptor antagonist, suggesting that it is mediated by substance P (SP). SP-induced contraction of M2-receptor KO mice did not differ from that of wild-type mice. SP immunoreactivity was located in enteric neurons, colocalized with M2 receptor immunoreactivity. These results suggest that atropine-sensitive phasic contraction is mainly mediated via the M3 receptor, and SP-mediated sustained contraction is negatively regulated by the M2 receptor at a presynaptic level.

  12. Polymorphic Contracts

    NASA Astrophysics Data System (ADS)

    Belo, João Filipe; Greenberg, Michael; Igarashi, Atsushi; Pierce, Benjamin C.

    Manifest contracts track precise properties by refining types with predicates - e.g., {x : Int |x > 0 } denotes the positive integers. Contracts and polymorphism make a natural combination: programmers can give strong contracts to abstract types, precisely stating pre- and post-conditions while hiding implementation details - for example, an abstract type of stacks might specify that the pop operation has input type {x :α Stack |not ( empty x )} . We formalize this combination by defining FH, a polymorphic calculus with manifest contracts, and establishing fundamental properties including type soundness and relational parametricity. Our development relies on a significant technical improvement over earlier presentations of contracts: instead of introducing a denotational model to break a problematic circularity between typing, subtyping, and evaluation, we develop the metatheory of contracts in a completely syntactic fashion, omitting subtyping from the core system and recovering it post facto as a derived property.

  13. Fault seal analysis of Okan and Meren fields, Nigeria

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

    Eisenberg, R.A.; Brenneman, R.J.; Adeogba, A.A.

    The sealing capacity and the dynamic seal behavior of faults between juxtaposed reservoirs were analyzed for Okan and Meren fields, offshore Nigeria. In both fields correlations were found between reservoir performance, juxtaposed fluid types, oil geochemistry, interpreted fluid contact relationships, fault sealing/leaking condition, and calculated smear gouge ratios. Integration of these data has been invaluable in quantifying fault seal risk and may effect depletion strategies for fault-juxtaposed reservoirs within these fields. Fault plane sections defined reservoir juxtapositions and aided visualization of potential cross-fault spill points. Smear gouge ratios calculated from E-logs were used to estimate the composition of fault-gouge materialsmore » between the juxtaposed reservoirs. These tools augmented interpretation of seal/nonseal character based on fluid contact relationships in proved reservoirs and, in addition, were used to quantify fault seal risk of untested fault-dependent closures in Okan. The results of these analyses were then used to interpret production-induced fault seal breakdown within the G-sands and also to risk seal integrity of fault dependent closures within the untested O-sands in an adjacent, upthrown fault block. Within this fault block the presence of potential fault intersection leak points and large areas of sand/sand juxtaposition with high smear gouge ratios (low sealing potential) limits potential reserves within the O-sand package. In Meren Field the E- and G-sands are juxtaposed, on different pressure decline, geochemically distinct, and are characterized by low smear gouge ratios. In contrast, specific G- and H-sands, juxtaposed across the same fault, contain similar OOWCs and are characterized by high smear gouge ratios. The cross-sealing and/or cross-leaking nature of compartment boundaries at Meren is related to fault displacement variation and the composition of displaced stratigraphy.« less

  14. Sealing vessels up to 7 mm in diameter solely with ultrasonic technology.

    PubMed

    Timm, Richard W; Asher, Ryan M; Tellio, Karalyn R; Welling, Alissa L; Clymer, Jeffrey W; Amaral, Joseph F

    2014-01-01

    Ultrasonic energy is a mainstay in the armamentarium of surgeons, providing multifunctionality, precision, and control when dissecting and sealing vessels up to 5 mm in diameter. Historically, the inability to seal vessels in the 5-7 mm range has been perceived as an inherent limitation of ultrasonic technology. The purpose of this study was to evaluate sealing of vessels up to 7 mm in diameter with an ultrasonic device that modulates energy delivery during the sealing period. In ex vivo benchtop and in vivo acute and survival preclinical models, a new ultrasonic device, Harmonic ACE(®)+7 Shears (Harmonic 7), was compared with advanced bipolar devices in sealing vessels 1-7 mm in diameter with respect of burst pressure, seal reliability, and seal durability. Lateral thermal damage and transection time were also evaluated. Ex vivo tests of Harmonic 7 demonstrated significantly greater median burst pressures than an advanced bipolar device both for vessels <5 mm in diameter (1,078 mmHg and 836 mmHg, respectively, P=0.046) and for those in the range of 5-7 mm (1,419 mmHg and 591 mmHg, P<0.001). In vivo tests in porcine and caprine models demonstrated similar rates of hemostasis between Harmonic 7 and advanced bipolar devices, with high success rates at initial transection and seal durability of 100% after a 30-day survival period. Sealing 5-7 mm vessels is not a limitation of the type of energy used but of how energy is delivered to tissue. These studies document the ability of ultrasonic energy alone to reliably seal large vessels 5-7 mm in diameter, with significantly greater burst pressure observed in in vitro studies than those observed with an advanced bipolar technology when energy delivery is modulated during the sealing cycle. Furthermore, the seals created in 5-7 mm vessels are shown to be reliable and durable in in vivo preclinical studies.

  15. 48 CFR 1316.405-2 - Cost-plus-award-fee contracts.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Cost-plus-award-fee... CONTRACTING METHODS AND CONTRACT TYPES TYPES OF CONTRACTS Incentive Contracts 1316.405-2 Cost-plus-award-fee contracts. Insert clause 1352.216-72, Determination of Award Fee, in all cost-plus-award-fee contracts. ...

  16. 48 CFR 416.405-2 - Cost-plus-award-fee contracts.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 4 2010-10-01 2010-10-01 false Cost-plus-award-fee... CONTRACTING METHODS AND CONTRACT TYPES TYPES OF CONTRACTS Incentive Contracts 416.405-2 Cost-plus-award-fee contracts. The HCA may designate an acquisition official other than the contracting officer as the fee...

  17. Novel application of polyelectrolyte multilayers as nanoscopic closures with hermetic sealing.

    PubMed

    Marcott, Stephanie A; Ada, Sena; Gibson, Phillip; Camesano, Terri A; Nagarajan, R

    2012-03-01

    Closure systems for personnel protection applications, such as protective clothing or respirator face seals, should provide effective permeation barrier to toxic gases. Currently available mechanical closure systems based on the hook and loop types (example, Velcro) do not provide adequate barrier to gas permeation. To achieve hermetic sealing, we propose a nonmechanical, nanoscopic molecular closure system based on complementary polyelectrolyte multilayers, one with a polycation outermost layer and the other with a polyanion outermost layer. The closure surfaces were prepared by depositing polyelectrolyte multilayers under a variety of deposition conditions, on conformable polymer substrates (thin films of polyethylene teraphthalate, PET or polyimide, PI). The hermetic sealing property of the closures was evaluated by measuring the air flow resistance using the dynamic moisture permeation cell (DMPC) at different humidity conditions. The DMPC measurements show that the polyelectrolyte multilayer closures provide significantly large resistance to air flow, approximately 20-800 times larger than that possible with conventional hook and loop type closure systems, at all humidity levels (from 5 to 95% relative humidity). Hence, from the point of view of providing a hermetic seal against toxic gas permeation, the polyelectrolyte multilayer closures are viable candidates for further engineering development. However, the adhesive strength of the multilayer closures measured by atomic force microscopy suggests that the magnitude of adhesion is much smaller than what is possible with mechanical closures. Therefore, we envisage the development of a composite closure system combining the mechanical closure to provide strong adhesion and the multilayer closure to provide hermetic sealing. © 2012 American Chemical Society

  18. 48 CFR 816.102 - Policies.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Policies. 816.102 Section... CONTRACT TYPES TYPES OF CONTRACTS Selecting Contract Types 816.102 Policies. (a) Contracting officers must obtain technical review of solicitations that include a clause that provides for economic price...

  19. A new stylolite classification scheme to estimate compaction and local permeability variations

    NASA Astrophysics Data System (ADS)

    Koehn, D.; Rood, M. P.; Beaudoin, N.; Chung, P.; Bons, P. D.; Gomez-Rivas, E.

    2016-12-01

    We modeled the geometrical roughening of bedding-parallel, mainly layer-dominated stylolites in order to understand their structural evolution, to present an advanced classification of stylolite shapes and to relate this classification to chemical compaction and permeability variations at stylolites. Stylolites are rough dissolution seams that develop in sedimentary basins during chemical compaction. In the Zechstein 2 carbonate units, an important lean gas reservoir in the southern Permian Zechstein basin in Germany, stylolites influence local fluid flow, mineral replacement reactions and hence the permeability of the reservoir. Our simulations demonstrate that layer-dominated stylolites can grow in three distinct stages: an initial slow nucleation phase, a fast layer-pinning phase and a final freezing phase if the layer is completely dissolved during growth. Dissolution of the pinning layer and thus destruction of the stylolite's compaction tracking capabilities is a function of the background noise in the rock and the dissolution rate of the layer itself. Low background noise needs a slower dissolving layer for pinning to be successful but produces flatter teeth than higher background noise. We present an advanced classification based on our simulations and separate stylolites into four classes: (1) rectangular layer type, (2) seismogram pinning type, (3) suture/sharp peak type and (4) simple wave-like type. Rectangular layer type stylolites are the most appropriate for chemical compaction estimates because they grow linearly and record most of the actual compaction (up to 40 mm in the Zechstein example). Seismogram pinning type stylolites also provide good tracking capabilities, with the largest teeth tracking most of the compaction. Suture/sharp peak type stylolites grow in a non-linear fashion and thus do not record most of the actual compaction. However, when a non-linear growth law is used, the compaction estimates are similar to those making use of the rectangular layer type stylolites. Simple wave-like stylolites are not useful for compaction estimates, since their growth is highly non-linear with a very low growth exponent. In the case where sealing material is collected at the tooth during dissolution, stylolites can act as barriers for local fluid flow as they intensify sealing capabilities of pinning layers. However, the development of teeth and spikes offsets and thus destroys continuous stylolite seams so that the permeability across the stylolite becomes very heterogeneous and they are no continuous barriers. This behavior is best shown in rectangular layer and seismogram pinning type stylolites that develop efficient fluid barriers at teeth tips but destroy sealing capabilities of layers by offsetting them at the flank, leading to a permeability anisotropy along 2-D stylolite planes. Suture/sharp peak stylolites can create fluid barriers if they collect enough sealing material. However, if the collecting material does not seal or if spikes offset the sealing material the stylolite leaks. We propose that our classification can be used to realistically estimate chemical compaction in reservoirs and gives an indication on how heterogeneous the permeability of stylolites can be.

  20. Sealed nickel cadmium batteries

    NASA Astrophysics Data System (ADS)

    Raudszus, W.; Kiehne, H. A.; Cloke, F. R.

    1982-10-01

    The design, manufacture, and application of maintenance-free sealed NiCd batteries are surveyed. The principles of electrochemical power supplies and the history of the development of NiCd cells are reviewed. The batteries produced by Varta Batterie AG are presented; topics discussed include design parameters, electrical and physical characteristics, performance under adverse conditions, type range, production, and quality control. Application techniques, including cell-type choice, charging units and charging circuits, and the construction of standby power supplies, are considered, with reference to national and international standards of performance and classification. No individual items are abstracted in this volume

  1. Effect of collagen and elastin content on the burst pressure of human blood vessel seals formed with a bipolar tissue sealing system.

    PubMed

    Latimer, Cassandra A; Nelson, Meghan; Moore, Camille M; Martin, Kimberly E

    2014-01-01

    Bipolar devices are routinely used to seal blood vessels instead of sutures and clips. Recent work examining the impact of vascular proteins on bipolar seal performance found that collagen and elastin (CE) content within porcine arteries was a significant predictor of a vessel's burst pressure (VBPr). This study examined seal performance across a range of human blood vessels to investigate whether a similar relationship existed. In addition, we compared VBPr and CE content between porcine and human blood vessels. Our primary hypothesis is that higher collagen-to-elastin ratio will predict higher VBPr in human vasculature. In six cadavers, 185 blood vessels from nine anatomic locations were sealed using a bipolar electrosurgical system. A linear mixed model framework was used to evaluate the impact of vessel diameter and CE content on VBPr. The effect of CE ratio on VBPr is modified by vessel size, with CE ratio having larger influence on VBPr in smaller diameter vessels. Seal burst pressure of vessels 2-5 mm in diameter was significantly associated with their CE content. Comparison of average VBPr between species revealed porcine carotid and iliac arteries (440-670 mmHg) to be the best vessel types for predicting the seal strength of most human blood vessels (420-570 mmHg) examined. CE content significantly modified the seal strength of small to medium sized blood vessels but had limited impact on vessels >5 mm. Copyright © 2014 Elsevier Inc. All rights reserved.

  2. 40 CFR 63.9306 - What are my continuous parameter monitoring system (CPMS) installation, operation, and...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... device to the atmosphere. (ii) Car-seal or lock-and-key valve closures. Secure any bypass line valve in the closed position with a car-seal or a lock-and-key type configuration. You must visually inspect... components for integrity and electrical connections for continuity, oxidation, and galvanic corrosion. (d...

  3. 19 CFR 18.4a - Containers or road vehicles accepted for transport under customs seal; requirements.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Containers or road vehicles accepted for transport... General Provisions § 18.4a Containers or road vehicles accepted for transport under customs seal... design type approval by a competent authority, and (iii) if the container or road vehicle hauling the...

  4. Replacement of Asbestos Aboard Naval Aircraft.

    DTIC Science & Technology

    1981-11-10

    braided -sleeving hose coverings, tapes, wire insulation, furnace linings, blankets, gaskets, and seals. CHEMICAL ANALYSIS A12 03 62% Si0 2 24...Physical, Chemical, and Mineralogical Properties of Varieties of Asbestos ............................................ 7 III Inorganic (Non- Metal ...all types Gakets (for sealing nonmoving parts) Asbestos, asbetos- metallic , and asbetos-ubber Packing (except leather, rubber, and metal ) and abestos

  5. 75 FR 28485 - Airworthiness Directives; Gulfstream Aerospace LP (Type Certificate Previously Held by Israel...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-21

    ... caution light CABIN DOOR signaling both MED Improper Closure and MED Inflatable Seal Failure into two separate lights: CABIN DOOR and CABIN DOOR SEAL. 2. Converting the separated CABIN DOOR Caution light into a Warning light by changing its color to red. Note: Aircraft Flight Manuals (AFM'S) refer to these...

  6. 48 CFR 216.306 - Cost-plus-fixed-fee contracts.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Cost-plus-fixed-fee... SYSTEM, DEPARTMENT OF DEFENSE CONTRACTING METHODS AND CONTRACT TYPES TYPES OF CONTRACTS Cost-Reimbursement Contracts 216.306 Cost-plus-fixed-fee contracts. (c) Limitations. (i) Except as provided in...

  7. 48 CFR 1816.202-70 - NASA contract clause.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 6 2012-10-01 2012-10-01 false NASA contract clause. 1816.202-70 Section 1816.202-70 Federal Acquisition Regulations System NATIONAL AERONAUTICS AND SPACE ADMINISTRATION CONTRACTING METHODS AND CONTRACT TYPES TYPES OF CONTRACTS Fixed-Price Contracts 1816.202-70 NASA...

  8. 48 CFR 1816.406-70 - NASA contract clauses.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 6 2010-10-01 2010-10-01 true NASA contract clauses. 1816.406-70 Section 1816.406-70 Federal Acquisition Regulations System NATIONAL AERONAUTICS AND SPACE ADMINISTRATION CONTRACTING METHODS AND CONTRACT TYPES TYPES OF CONTRACTS Incentive Contracts 1816.406-70 NASA...

  9. 48 CFR 1816.406-70 - NASA contract clauses.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 6 2012-10-01 2012-10-01 false NASA contract clauses. 1816.406-70 Section 1816.406-70 Federal Acquisition Regulations System NATIONAL AERONAUTICS AND SPACE ADMINISTRATION CONTRACTING METHODS AND CONTRACT TYPES TYPES OF CONTRACTS Incentive Contracts 1816.406-70 NASA...

  10. 48 CFR 1816.406-70 - NASA contract clauses.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 6 2011-10-01 2011-10-01 false NASA contract clauses. 1816.406-70 Section 1816.406-70 Federal Acquisition Regulations System NATIONAL AERONAUTICS AND SPACE ADMINISTRATION CONTRACTING METHODS AND CONTRACT TYPES TYPES OF CONTRACTS Incentive Contracts 1816.406-70 NASA...

  11. 48 CFR 1816.406-70 - NASA contract clauses.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 6 2014-10-01 2014-10-01 false NASA contract clauses. 1816.406-70 Section 1816.406-70 Federal Acquisition Regulations System NATIONAL AERONAUTICS AND SPACE ADMINISTRATION CONTRACTING METHODS AND CONTRACT TYPES TYPES OF CONTRACTS Incentive Contracts 1816.406-70 NASA...

  12. 48 CFR 1816.202-70 - NASA contract clause.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 6 2011-10-01 2011-10-01 false NASA contract clause. 1816.202-70 Section 1816.202-70 Federal Acquisition Regulations System NATIONAL AERONAUTICS AND SPACE ADMINISTRATION CONTRACTING METHODS AND CONTRACT TYPES TYPES OF CONTRACTS Fixed-Price Contracts 1816.202-70 NASA...

  13. 48 CFR 1816.202-70 - NASA contract clause.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 6 2010-10-01 2010-10-01 true NASA contract clause. 1816.202-70 Section 1816.202-70 Federal Acquisition Regulations System NATIONAL AERONAUTICS AND SPACE ADMINISTRATION CONTRACTING METHODS AND CONTRACT TYPES TYPES OF CONTRACTS Fixed-Price Contracts 1816.202-70 NASA...

  14. 48 CFR 1816.202-70 - NASA contract clause.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 6 2014-10-01 2014-10-01 false NASA contract clause. 1816.202-70 Section 1816.202-70 Federal Acquisition Regulations System NATIONAL AERONAUTICS AND SPACE ADMINISTRATION CONTRACTING METHODS AND CONTRACT TYPES TYPES OF CONTRACTS Fixed-Price Contracts 1816.202-70 NASA...

  15. 48 CFR 1816.202-70 - NASA contract clause.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 6 2013-10-01 2013-10-01 false NASA contract clause. 1816.202-70 Section 1816.202-70 Federal Acquisition Regulations System NATIONAL AERONAUTICS AND SPACE ADMINISTRATION CONTRACTING METHODS AND CONTRACT TYPES TYPES OF CONTRACTS Fixed-Price Contracts 1816.202-70 NASA...

  16. 48 CFR 1816.406-70 - NASA contract clauses.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 6 2013-10-01 2013-10-01 false NASA contract clauses. 1816.406-70 Section 1816.406-70 Federal Acquisition Regulations System NATIONAL AERONAUTICS AND SPACE ADMINISTRATION CONTRACTING METHODS AND CONTRACT TYPES TYPES OF CONTRACTS Incentive Contracts 1816.406-70 NASA...

  17. 48 CFR 16.304 - Cost-plus-incentive-fee contracts.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 1 2011-10-01 2011-10-01 false Cost-plus-incentive-fee contracts. 16.304 Section 16.304 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION CONTRACTING METHODS AND CONTRACT TYPES TYPES OF CONTRACTS Cost-Reimbursement Contracts 16.304 Cost-plus...

  18. Effects of Polypropylene Orientation on Mechanical and Heat Seal Properties of Polymer-Aluminum-Polymer Composite Films for Pouch Lithium-Ion Batteries

    PubMed Central

    Chen, Jinyao; Yang, Feng; Kang, Jian; Cao, Ya; Xiang, Ming

    2018-01-01

    In this study, polyamide-aluminum foil-polypropylene (PA-Al-PP) composite films with different orientation status of the PP layer were prepared, and their morphology, tensile, peeling and heat seal behavior were studied. The comparative study of tensile and fracture behaviors of single-layer film of PA, Al and PP, as well as the composite films of PA-Al, PP-Al and PA-Al-PP revealed that in PA-Al-PP composite film, the PA layer with the highest tensile strength can share the tensile stress from the Al layer during stretching, while the PP layer with the lowest tensile strength can prevent further development of the small cracks on boundary of the Al layer during stretching. Moreover, the study of heat seal behavior suggested that both the orientation status and the heat seal conditions were important factors in determining the heat seal strength (HSS) and failure behavior of the sample. Four failure types were observed, and a clear correspondence between HSS and failure types was found. The results also elucidated that for the composite film, only in the cases where the tensile stress was efficiently released by each layer during HSS measurement could the composite film exhibit desired high HSS that was even higher than its tensile strength. PMID:29337881

  19. Esophageal contractions in type 3 achalasia esophagus: simultaneous or peristaltic?

    PubMed Central

    Kim, Tae Ho; Patel, Nirali; Ledgerwood-Lee, Melissa

    2016-01-01

    Absence of peristalsis and impaired relaxation of lower esophageal sphincter are the hallmarks of achalasia esophagus. Based on the pressurization patterns, achalasia has been subdivided into three subtypes. The goal of our study was to evaluate the esophageal contraction pattern and bolus clearance in type 3 achalasia esophagus. High-resolution manometry (HRM) recordings of all patients diagnosed with achalasia esophagus in our center between the years 2011 and 2013 were reviewed. Recordings of 36 patients with type 3 achalasia were analyzed for the characteristics of swallow-induced “simultaneous esophageal contraction.” The HRM impedance recordings of 14 additional patients with type 3 achalasia were analyzed for bolus clearance from the impedance recording. Finally, the HRM impedance along with intraluminal ultrasound imaging was conducted in six patients to further characterize the simultaneous esophageal contractions. Among 187 achalasia patients, 30 were type 1, 121 type 2, and 36 type 3. A total of 434 swallows evaluated in type 3 achalasia patients revealed that 95% of the swallow-induced contractions met criteria for simultaneous esophageal contraction, based on the onset of contraction. Interestingly, the peak and termination of the majority of simultaneous esophageal contractions were sequential. The HRM impedance revealed that 94% of the “simultaneous contractions” were associated with complete bolus clearance. Ultrasound image analysis revealed that baseline muscle thickness of patients in type 3 achalasia is larger than normal but the pattern of axial shortening is similar to that in normal subjects. The majority of esophageal contractions in type 3 achalasia are not true simultaneous contractions because the peak and termination of contraction are sequential and they are associated with complete bolus clearance. PMID:26950858

  20. Design of a factorial experiment with randomization restrictions to assess medical device performance on vascular tissue.

    PubMed

    Diestelkamp, Wiebke S; Krane, Carissa M; Pinnell, Margaret F

    2011-05-20

    Energy-based surgical scalpels are designed to efficiently transect and seal blood vessels using thermal energy to promote protein denaturation and coagulation. Assessment and design improvement of ultrasonic scalpel performance relies on both in vivo and ex vivo testing. The objective of this work was to design and implement a robust, experimental test matrix with randomization restrictions and predictive statistical power, which allowed for identification of those experimental variables that may affect the quality of the seal obtained ex vivo. The design of the experiment included three factors: temperature (two levels); the type of solution used to perfuse the artery during transection (three types); and artery type (two types) resulting in a total of twelve possible treatment combinations. Burst pressures of porcine carotid and renal arteries sealed ex vivo were assigned as the response variable. The experimental test matrix was designed and carried out as a split-plot experiment in order to assess the contributions of several variables and their interactions while accounting for randomization restrictions present in the experimental setup. The statistical software package SAS was utilized and PROC MIXED was used to account for the randomization restrictions in the split-plot design. The combination of temperature, solution, and vessel type had a statistically significant impact on seal quality. The design and implementation of a split-plot experimental test-matrix provided a mechanism for addressing the existing technical randomization restrictions of ex vivo ultrasonic scalpel performance testing, while preserving the ability to examine the potential effects of independent factors or variables. This method for generating the experimental design and the statistical analyses of the resulting data are adaptable to a wide variety of experimental problems involving large-scale tissue-based studies of medical or experimental device efficacy and performance.

  1. 48 CFR 16.305 - Cost-plus-award-fee contracts.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... CONTRACTING METHODS AND CONTRACT TYPES TYPES OF CONTRACTS Cost-Reimbursement Contracts 16.305 Cost-plus-award... consisting of (a) a base amount (which may be zero) fixed at inception of the contract and (b) an award amount, based upon a judgmental evaluation by the Government, sufficient to provide motivation for...

  2. 48 CFR 16.205 - Fixed-price contracts with prospective price redetermination.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Fixed-price contracts with prospective price redetermination. 16.205 Section 16.205 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION CONTRACTING METHODS AND CONTRACT TYPES TYPES OF CONTRACTS Fixed-Price Contracts 16.205...

  3. Failure of cap-rock seals as determined from mechanical stratigraphy, stress history, and tensile-failure analysis of exhumed analogs

    DOE PAGES

    Petrie, E. S.; Evans, J. P.; Bauer, S. J.

    2014-11-01

    In this study, the sedimentologic and tectonic histories of clastic cap rocks and their inherent mechanical properties control the nature of permeable fractures within them. The migration of fluid through mm- to cm-scale fracture networks can result in focused fluid flow allowing hydrocarbon production from unconventional reservoirs or compromising the seal integrity of fluid traps. To understand the nature and distribution of subsurface fluid-flow pathways through fracture networks in cap-rock seals we examine four exhumed Paleozoic and Mesozoic seal analogs in Utah. We combine these outcrop analyses with subsidence analysis, paleoloading histories, and rock-strength testing data in modified Mohr–Coulomb–Griffith analysesmore » to evaluate the effects of differential stress and rock type on fracture mode.« less

  4. Shaft seals with an easily removable cylinder holder for low-pressure steam turbines

    NASA Astrophysics Data System (ADS)

    Zakharov, A. E.; Rodionov, D. A.; Pimenov, E. V.; Sobolev, A. S.

    2016-01-01

    The article is devoted to the problems that occur at the operation of LPC shaft seals (SS) of turbines, particularly, their bearings. The problems arising from the deterioration of oil-protecting rings of SS and bearings and also the consequences in which they can result are considered. The existing SS housing construction types are considered. Their operational features are specified. A new SS construction type with an easily removable holder is presented. The construction of its main elements is described. The sequence of operations of the repair personnel at the restoration of the new SS type spacings is proposed. The comparative analysis of the new and the existing SS construction types is carried out. The assessment results of the efficiency, the operational convenience, and the economic effect after the installation of the new type seals are given. The conclusions about the offered construction prospects are made by results of the comparative analysis and the carried-out assessment. The main advantage of this design is the possibility of spacings restoration both in SS and in oil-protecting rings during a short-term stop of a turbine, even without its cooling. This construction was successfully tested on the working K-300-23.5 LMP turbine. However, its adaptation for other turbines is quite possible.

  5. 48 CFR 15.402 - Pricing policy.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... determining the type of data required: (i) No additional data from the offeror, if the price is based on... reasonable price. (3) Obtain the type and quantity of data necessary to establish a fair and reasonable price... AND CONTRACT TYPES CONTRACTING BY NEGOTIATION Contract Pricing 15.402 Pricing policy. Contracting...

  6. 48 CFR 15.402 - Pricing policy.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... determining the type of data required: (i) No additional data from the offeror, if the price is based on... reasonable price. (3) Obtain the type and quantity of data necessary to establish a fair and reasonable price... AND CONTRACT TYPES CONTRACTING BY NEGOTIATION Contract Pricing 15.402 Pricing policy. Contracting...

  7. 48 CFR 15.402 - Pricing policy.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... determining the type of data required: (i) No additional data from the offeror, if the price is based on... reasonable price. (3) Obtain the type and quantity of data necessary to establish a fair and reasonable price... AND CONTRACT TYPES CONTRACTING BY NEGOTIATION Contract Pricing 15.402 Pricing policy. Contracting...

  8. 29 CFR 4.111 - Contracts “to furnish services.”

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... the types of services which may be contracted for under a contract the principal purpose of which is to furnish services. Further, the nomenclature, type, or particular form of contract used by... indirectly through the definition of service employee the Act does not define, or limit, the types of...

  9. 48 CFR 15.401 - Definitions.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... AND CONTRACT TYPES CONTRACTING BY NEGOTIATION Contract Pricing 15.401 Definitions. As used in this subpart— Price means cost plus any fee or profit applicable to the contract type. Subcontract (except as...

  10. Guidelines for cost control and analysis of cost-type research and development contracts

    NASA Technical Reports Server (NTRS)

    Sibbers, C. W.

    1981-01-01

    The cost information which should be obtained from a contractor(s) on a major, cost type research and development contract(s), and the analyses and effective use of these data are discussed. Specific type(s) of information which should be required, methods for analyzing such information, and methods for effectively using the results of such analyses to enhance NASA contract and project management are included. The material presented is based primarily on the principal methods which have been effectively used in the management of major cost type research and development contracts.

  11. 48 CFR 16.405-2 - Cost-plus-award-fee contracts.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... CONTRACTING METHODS AND CONTRACT TYPES TYPES OF CONTRACTS Incentive Contracts 16.405-2 Cost-plus-award-fee... during performance and that is sufficient to provide motivation for excellence in the areas of cost... consisting of (1) a base amount fixed at inception of the contract, if applicable and at the discretion of...

  12. Rod-cone based color vision in seals under photopic conditions.

    PubMed

    Oppermann, Daniela; Schramme, Jürgen; Neumeyer, Christa

    2016-08-01

    Marine mammals have lost the ability to express S-cone opsin, and possess only one type of M/L-cone in addition to numerous rods. As they are cone monochromats they should be color blind. However, early behavioral experiments with fur seals and sea lions indicated discrimination ability between many shades of grey and blue or green. On the other hand, most recent training experiments with harbor seals under "mesopic" conditions demonstrated rod based color blindness (Scholtyssek et al., 2015). In our experiments we trained two harbor seals (Phoca vitulina) and two South African fur seals (Arctocephalus pusillus) with surface colors under photopic conditions. The seals had to detect a triangle on grey background shown on one of three test fields while the other two test fields were homogeneously grey. In a first series of experiments we determined brightness detection. We found a luminance contrast of >3% sufficient for correctly choosing the triangle. In the tests for color vision the triangle was blue, green or yellow in grey surround. The results show that the animals could see the colored triangle despite minimal or zero brightness contrast. Thus, seals have color vision based on the contribution of cones and rods even in bright daylight. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Numerical Simulation of Flow in a Whirling Annular Seal and Comparison with Experiments

    NASA Technical Reports Server (NTRS)

    Athavale, M. M.; Hendricks, R. C.; Steinetz, B. M.

    1995-01-01

    The turbulent flow field in a simulated annular seal with a large clearance/radius ratio (0.015) and a whirling rotor was simulated using an advanced 3D CFD code SCISEAL. A circular whirl orbit with synchronous whirl was imposed on the rotor center. The flow field was rendered quasi-steady by making a transformation to a totaling frame. Standard k-epsilon model with wall functions was used to treat the turbulence. Experimentally measured values of flow parameters were used to specify the seal inlet and exit boundary conditions. The computed flow-field in terms of the velocity and pressure is compared with the experimental measurements inside the seal. The agreement between the numerical results and experimental data with correction is fair to good. The capability of current advanced CFD methodology to analyze this complex flow field is demonstrated. The methodology can also be extended to other whirl frequencies. Half- (or sub-) synchronous (fluid film unstable motion) and synchronous (rotor centrifugal force unbalance) whirls are the most unstable whirl modes in turbomachinery seals, and the flow code capability of simulating the flows in steady as well as whirling seals will prove to be extremely useful in the design, analyses, and performance predictions of annular as well as other types of seals.

  14. Technological progress in sealed lead/acid batteries

    NASA Astrophysics Data System (ADS)

    Yamashita, J.; Nakashima, H.; Kasai, Y.

    A brief review is given of the history of the research and development of sealed lead/acid batteries during the 30 years since, in 1959, the Yuasa Battery Co. introduced a small-sized sealed battery as the power supply for portable television sets. In 1965, Yuasa began the full-scale mass production and sale of a small-sized sealed lead/acid battery under the NOYPER brand. In 1970, the use of a PbCa alloy grid was adopted, and there followed the successful development of a sealed battery with an oxygen-recombination facility. In 1976, Yuasa more or less established the basic technology for the valve-regulated sealed lead/acid battery — the NP battery — which is now the type in general use. Throughout the 1980s, Yuasa, has continued development in order to expand the sphere of application for the production technology of valve-regulated batteries for motorcycles, as well as for stationary duties with large capacities of 100 to 3000 A h. Recently, in order to improve the reliability and boost the output of sealed lead/acid batteries for employment in UPS power sources, Yuasa has been working intently on the design of a valve-regulated lead/acid battery with outstanding characteristics for high-rate discharge and resistance to high temperatures.

  15. Seal Formation Mechanism Beneath Animal Waste Holding Ponds

    NASA Astrophysics Data System (ADS)

    Cihan, A.; Tyner, J. S.; Wright, W. C.

    2005-12-01

    Infiltration of animal waste from holding ponds can cause contamination of groundwater. Typically, the initial flux from a pond decreases rapidly as a seal of animal waste particulates is deposited at the base of the pond. The purpose of this study was to investigate the mechanism of the seal formation. Twenty-four soil columns (10-cm diameter by 43-cm long) were hand-packed with sand, silty loam or clay soils. A 2.3 m column of dairy or swine waste was applied to the top of the each column. The leakage rate from each column was measured with respect to time to analyze the effect of seal formation on different soil textures and animal waste types. We tested our hypothesis that seal growth and the subsequent decrease of leachate production adheres to a filter cake growth model. Said model predicts that the cumulative leakage rate is proportional to the square root of time and to the square root of the height of the waste.

  16. Fretting in aircraft turbine engines

    NASA Technical Reports Server (NTRS)

    Johnson, R. L.; Bill, R. C.

    1974-01-01

    The problem of fretting in aircraft turbine engines is discussed. Critical fretting can occur on fan, compressor, and turbine blade mountings, as well as on splines, rolling element bearing races, and secondary sealing elements of face type seals. Structural fatigue failures have been shown to occur at fretted areas on component parts. Methods used by designers to reduce the effects of fretting are given.

  17. Hydrological balance and water transport processes of partially sealed soils

    NASA Astrophysics Data System (ADS)

    Timm, Anne; Wessolek, Gerd

    2017-04-01

    With increased urbanisation, soil sealing and its drastic effects on hydrological processes have received a lot of attention. Based on safety concerns, there has been a clear focus on urban drainage and prevention of urban floods caused by storm water events. For this reason, any kind of sealing is often seen as impermeable runoff generator that prevents infiltration and evaporation. While many hydrological models, especially storm water models, have been developed, there are only a handful of empirical studies actually measuring the hydrological balance of (partially) sealed surfaces. These challenge the general assumption of negligible infiltration and evaporation and show that these processes take place even for severe sealing such as asphalt. Depending on the material, infiltration from partially sealed surfaces can be equal to that of vegetated ones. Therefore, more detailed knowledge is needed to improve our understanding and models. In Berlin, two partially sealed weighable lysimeters were equipped with multiple temperature and soil moisture sensors in order to study their hydrological balance, as well as water and heat transport processes within the soil profile. This combination of methods affirms previous observations and offers new insights into altered hydrological processes of partially sealed surfaces at a small temporal scale. It could be verified that not all precipitation is transformed into runoff. Even for a relatively high sealing degree of concrete slabs with narrow seams, evaporation and infiltration may exceed runoff. Due to the lack of plant roots, the hydrological balance is mostly governed by precipitation events and evaporation generally occurs directly after rainfall. However, both surfaces allow for upward water transport from the upper underlying soil layers, sometimes resulting in relatively low evaporation rates on days without precipitation. The individual response of the surfaces differs considerably, which illustrates how important process orientated studies for different types of sealing material are.

  18. Factors Contributing to Pilot Valve Fuel Seal Extrusion in Orbiter PRCS Thrusters

    NASA Technical Reports Server (NTRS)

    Waller, J.M.; Saulsberry, R.L.; Albright, John D.

    2000-01-01

    Extrusion of the polytetrafluoroethylene (PTFE) pilot seal used in the monomethylhydrazine (fuel) valve of the Orbiter Primary Reaction Control System (PRCS) thrusters has been implicated in numerous on-orbit thruster failures and on-ground valve failures. Two extrusion mechanisms have been proposed, one or both may be occurring. The first mechanism is attributed to thermal expansion mismatch between adjacent PTFE and metal parts used in the fuel valve, and is referred to as thermal extrusion. The second mechanism is attributed to nitrogen tetroxide (oxidizer) leakage from the adjacent oxidizer valve on the same thruster during ground turnaround, and is referred to as oxidizer-induced extrusion. Model calculations of PTFE pilot seal in an exact pilot valve configuration show that extrusion can be caused by differential thermal expansion, without the intervening influence of oxidizer. Experimental data on semitrapped PTFE and TFM (modified PTFE) specimens simulating a fuel pilot valve configuration show that thermal extrusion 1) is incremental and irreversible, 2) increases with the size of the thermal excursion, 3) decreases with successive thermal cycling, and 4) is accompanied by gap formation. Both PTFE and TFM exhibit a higher affinity for oxidizer than fuel. The property changes associated with oxidizer uptake may explain why oxidizer seals do not exhibit extrusion. Impression replicas of fuel pilot seals removed from the Orbiter fleet show two types of extrusion: extrusion of the entire seal (loaded extrusion), or extrusion of non-sealing surface (unloaded extrusion). Both extrusion types may arise from differences in service history, rather than in failure mechanism. The plausibility oxidizer-induced extrusion was evaluated. Preliminary calculations suggest that enough energy, heat, or gas may be liberated under certain operational scenarios to cause catastrophic extrusion. However, given the lack of supporting data, conclusions implicating oxidizer leakage as a factor in extrusion must be made with caution.

  19. Spontaneous delayed sealing in selected patients with a primary type-Ia endoleak after endovascular aneurysm repair.

    PubMed

    Bastos Gonçalves, F; Verhagen, H J M; Vasanthananthan, K; Zandvoort, H J A; Moll, F L; van Herwaarden, J A

    2014-07-01

    Direct additional therapy is advised for type-Ia endoleaks detected on completion angiography after endovascular aneurysm repair (EVAR). Additional intraoperative endovascular procedures are, however, often challenging or not possible, and direct open conversion is unattractive. The results of a selective, conservative strategy for patients with primary type-Ia endoleak has been analysed. This was a retrospective, single-centre study (UMC, Utrecht, NL). From 2004 to 2008, all patients with a primary type-Ia endoleak and suitable anatomy for EVAR, stentgraft oversizing ≥15%, and optimal deployment were included. Complications during follow-up were studied and all sequential CTA scans were reviewed. These were compared with the remaining patients, treated during the same period. Fifteen patients were included (14 male, median age 77, range 67-85) with a median aneurysm diameter of 60 mm (48-80), an aneurysm neck diameter of 26 mm (21-32), a neck length of 29 mm (11-39), and infrarenal angulation of 49° (31-90). One patient suffered rupture 2 days after EVAR - leading to the only AAA-related death. Eight of the 15 type-Ia endoleaks disappeared spontaneously on the first postoperative CTA, obtained within 1 week of EVAR. On the second postoperative CTA, obtained a median of 5 months (1-12) after EVAR, all remaining endoleaks had sealed. One recurrence occurred at 4.85 years. During a median follow-up of 3.3 years, there were five secondary interventions. Compared with controls, there were more secondary (or recurrent) type-1a endoleaks (13% vs. 4%), endograft migrations (13% vs. 3%), sac growths (33% vs. 16%), and secondary interventions (33% vs. 23%). None of these differences however, were statistically significant. All but one of the primary type-Ia endoleaks sealed spontaneously. Until sealing, the risk of rupture persisted, but subsequently only one recurrence of type-Ia endoleak was seen. In selected patients, a conservative approach for primary type-Ia endoleaks may be justified. Copyright © 2014 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.

  20. 48 CFR 235.006 - Contracting methods and contract type.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Defense (Acquisition, Technology, and Logistics) (USD(AT&L)) of an intent not to exercise a fixed-price... award a fixed-price type contract for a development program effort unless— (1) The level of program risk permits realistic pricing; (2) The use of a fixed-price type contract permits an equitable and sensible...

  1. Evaluation of the user seal check on gross leakage detection of 3 different designs of N95 filtering facepiece respirators.

    PubMed

    Lam, Simon C; Lui, Andrew K F; Lee, Linda Y K; Lee, Joseph K L; Wong, K F; Lee, Cathy N Y

    2016-05-01

    The use of N95 respirators prevents spread of respiratory infectious agents, but leakage hampers its protection. Manufacturers recommend a user seal check to identify on-site gross leakage. However, no empirical evidence is provided. Therefore, this study aims to examine validity of a user seal check on gross leakage detection in commonly used types of N95 respirators. A convenience sample of 638 nursing students was recruited. On the wearing of 3 different designs of N95 respirators, namely 3M-1860s, 3M-1862, and Kimberly-Clark 46827, the standardized user seal check procedure was carried out to identify gross leakage. Repeated testing of leakage was followed by the use of a quantitative fit testing (QNFT) device in performing normal breathing and deep breathing exercises. Sensitivity, specificity, predictive values, and likelihood ratios were calculated accordingly. As indicated by QNFT, prevalence of actual gross leakage was 31.0%-39.2% with the 3M respirators and 65.4%-65.8% with the Kimberly-Clark respirator. Sensitivity and specificity of the user seal check for identifying actual gross leakage were approximately 27.7% and 75.5% for 3M-1860s, 22.1% and 80.5% for 3M-1862, and 26.9% and 80.2% for Kimberly-Clark 46827, respectively. Likelihood ratios were close to 1 (range, 0.89-1.51) for all types of respirators. The results did not support user seal checks in detecting any actual gross leakage in the donning of N95 respirators. However, such a check might alert health care workers that donning a tight-fitting respirator should be performed carefully. Copyright © 2016 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

  2. [Artificial heart--turbo type blood pump for long-term use].

    PubMed

    Akamatsu, Teruaki

    2003-05-01

    Shortage of donor heart for transplantation necessitates long-term artificial assist heart. Turbo-pump is smaller, simpler and cheaper than the pulsatile displacement type pump, but the turbo-pump has defect of thrombus formation at the shaft seal. Our centrifugal pump with magnetically suspended impellers overcomes this defect and is ready for clinical trials now. The structures and functions are described and are compared with the other newly-developed pump of the same kinds with us. And also the pumps of centrifugal type and axial-type, of which impellers are supported by pivots, are reviewed briefly from the stand point for long-term use. Other pumps are referred too: pumps with hydrodynamic bearing and a pump with the shaft seal which is washed and cooled by saline solution.

  3. 48 CFR 2016.307-70 - Contract provisions and clauses.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ..., Level of Effort, in solicitations for negotiated procurements containing labor costs other than maintenance services to be awarded on a cost reimbursement, cost sharing, cost-plus-award fee, cost-plus-fixed... COMMISSION CONTRACTING METHODS AND CONTRACT TYPES TYPES OF CONTRACTS Cost Reimbursement Contracts 2016.307-70...

  4. 48 CFR 916.405-2 - Cost-plus-award-fee contracts.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ..., output, be it hardware, research and development, demonstration or services, together with business... CONTRACTING METHODS AND CONTRACT TYPES TYPES OF CONTRACTS Incentive Contracts 916.405-2 Cost-plus-award-fee... appropriate) and business management considerations tailored to the needs of the particular situation. In...

  5. 48 CFR 415.404-4 - Profit.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...) Termination settlements; and (v) Cost-plus-award-fee contracts; (b) Unless otherwise restricted by contracting... CONTRACT TYPES CONTRACTING BY NEGOTIATION Contract Pricing 415.404-4 Profit. (a)(1) USDA will use a... negotiation is based on cost analysis. (2) The following types of acquisitions are exempt from the...

  6. 48 CFR 35.006 - Contracting methods and contract type.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... indicated a high degree of probability that development is feasible and (2) the Government has determined... SPECIAL CATEGORIES OF CONTRACTING RESEARCH AND DEVELOPMENT CONTRACTING 35.006 Contracting methods and..., performance objectives, and specifications for the work can be defined will largely determine the type of...

  7. 48 CFR 970.1504-1-4 - Types of contracts and fee arrangements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...-based management contract, those contract types which incentivize performance and cost control are... performance result or outcome. (e) Because the nature and complexity of the work performed under a management... AGENCY SUPPLEMENTARY REGULATIONS DOE MANAGEMENT AND OPERATING CONTRACTS Contracting by Negotiation 970...

  8. Experimental Investigations of Exciting Forces Caused by Flow in Labyrinth Seals

    NASA Technical Reports Server (NTRS)

    Thieleke, G.; Stetter, H.

    1991-01-01

    The interaction of the flow through the labyrinth seals with the shaft of the rotor can have an effect on the stability of turbomachines. Thus, the excited forces, so-called cross forces or nonconservative forces, arise, which act perpendicular to the rotor eccentricity. This effect is caused by an unsymmetrical pressure distribution within the labyrinth cavities. Experimental studies were carried out for different types of labyrinth geometries: two staggered labyrinths with teeth on the stator and grooved rotor as well as a full and a convergent stepped labyrinth. These labyrinths can be found on the tip shrouding of bladings in steam or gas turbines. The following parameters were varied in the test facility: geometry of the labyrinth seals (number of cavities, inlet region), shaft rotation, pressure difference on the seal, entry swirl and eccentricity of the rotor. The results are presented for stiffness coefficients of the labyrinth seals, leakage flow and circumferential flow in each cavity which was measured with special probes. Generally, the inlet swirl has the greatest influence on the coefficients of the seals. The experimental results were compared with theoretical results and were in good agreement.

  9. 48 CFR 205.303 - Announcement of contract awards.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... (if significant work is performed at a different location); (4) Funding data. Type of appropriation... DD-LA- (AR) 1279; (D) Including, as a minimum, the following— (1) Contract data. Contract number... contract, description of what is being bought, contract type, whether any of the buy was for foreign...

  10. 48 CFR 205.303 - Announcement of contract awards.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... (if significant work is performed at a different location); (4) Funding data. Type of appropriation... DD-LA- (AR) 1279; (D) Including, as a minimum, the following— (1) Contract data. Contract number... contract, description of what is being bought, contract type, whether any of the buy was for foreign...

  11. 48 CFR 205.303 - Announcement of contract awards.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... (if significant work is performed at a different location); (4) Funding data. Type of appropriation... DD-LA- (AR) 1279; (D) Including, as a minimum, the following— (1) Contract data. Contract number... contract, description of what is being bought, contract type, whether any of the buy was for foreign...

  12. 48 CFR 205.303 - Announcement of contract awards.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... (if significant work is performed at a different location); (4) Funding data. Type of appropriation... DD-LA- (AR) 1279; (D) Including, as a minimum, the following— (1) Contract data. Contract number... contract, description of what is being bought, contract type, whether any of the buy was for foreign...

  13. 48 CFR 205.303 - Announcement of contract awards.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... (if significant work is performed at a different location); (4) Funding data. Type of appropriation... DD-LA- (AR) 1279; (D) Including, as a minimum, the following— (1) Contract data. Contract number... contract, description of what is being bought, contract type, whether any of the buy was for foreign...

  14. 48 CFR 215.404-71-3 - Contract type risk and working capital adjustment.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... varying contract types. The working capital adjustment is an adjustment added to the profit objective for... Base (item 20) Profit objective 24. CONTRACT type risk (1) (2) (3) Cost financed Length factor Interest... money. (3) Multiply (1) by (2). (4) Only complete this block when the prospective contract is a fixed...

  15. 48 CFR 215.404-71-3 - Contract type risk and working capital adjustment.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... varying contract types. The working capital adjustment is an adjustment added to the profit objective for... Base (item 20) Profit objective 24. CONTRACT type risk (1) (2) (3) Cost financed Length factor Interest... money. (3) Multiply (1) by (2). (4) Only complete this block when the prospective contract is a fixed...

  16. 48 CFR 215.404-71-3 - Contract type risk and working capital adjustment.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... varying contract types. The working capital adjustment is an adjustment added to the profit objective for... Base (item 20) Profit objective 24. CONTRACT type risk (1) (2) (3) Cost financed Length factor Interest... money. (3) Multiply (1) by (2). (4) Only complete this block when the prospective contract is a fixed...

  17. Performance degradation of ferrofluidic feedthroughs in a mixed irradiation field

    NASA Astrophysics Data System (ADS)

    Simos, Nikolaos; Fernandes, S.; Mittig, Wolfgang; Pellemoine, Frederique; Avilov, M.; Kostin, M.; Mausner, L.; Ronningen, R.; Schein, M.; Bollen, G.

    2017-01-01

    Ferrofluidic feedthrough (FF) rotary seals containing either NdFeB or SmCo-type permanent magnets have been considered for use in the target and beam dump systems of the Facility for Rare Isotope Beams (FRIB). To evaluate their performance under irradiation three FF seals were irradiated in a mixed field consisting of fast neutrons, protons and γ-rays to an average absorbed dose of 0.2, 2.0, and 20.0 MGy at the Brookhaven Linac Isotope Producer facility (BLIP). The radiation types and energy profiles mimic those expected at the FRIB facility. Degradation of the operational performance of these devices due to irradiation is expected to be the result of the de-magnetization of the permanent magnets contained within the seal and the changes in the ferrofluid properties. Post-irradiation performance was evaluated by determining the ferrofluidic seal vacuum tightness and torque under static and dynamic conditions. The study revealed that the ferrofluidic feedthrough seal irradiated to a dose of 0.2 MGy maintained its vacuum tightness under both static and rotational condition while the one irradiated to a dose of 2.0 MGy exhibited signs of ferrofluid damage but no overall performance loss. At 20 MGy dose the effects of irradiation on the ferrofluid properties (viscosity and particle agglomeration) were shown to be severe. Furthermore, limited de-magnetization of the annular shaped Nd2Fe14B and Sm2Co17 magnets located within the irradiated FFs was observed for doses of 0.2 MGy and 20 MGy respectively.

  18. 40 CFR 35.938-3 - Type of contract.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... STATE AND LOCAL ASSISTANCE Grants for Construction of Treatment Works-Clean Water Act § 35.938-3 Type of... other acceptable type of contract. The cost-plus-percentage-of-cost contract shall not be used in any...

  19. Investigation of Standing Seam Metal Roofing.

    DTIC Science & Technology

    1986-06-01

    Alloy Coatings weather, a dull -gray zinc carbonate film forms which Two types of alloy coatings are applied, depending protects the remaining zinc from...difficult to rectangular penetrations such as skylights , rooftop seal completely between tie flashing and the roof equipment, and ventilation ducts; pipe...finish appear dulled . Barring unforeseen condition, coupled with a poorly sealed lap joint in damage, a yearlx washing is all the maintenance the the

  20. Metallic seal for thermal barrier coating systems

    NASA Technical Reports Server (NTRS)

    Miller, Robert A. (Inventor)

    1990-01-01

    The invention is particularly concerned with sealing thermal barrier coating systems of the type in use and being contemplated for use in diesel and other internal combustion engines. The invention also would find application in moderately high temperature regions of gas turbine engines and any other application employing a thermal barrier coating at moderate temperatures. Ni-35Cr-6Al-1Y, Ni-35Cr-6Al-1Yb, or other metallic alloy denoted as MCrAlx is applied over a zirconia-based thermal barrier overlayer. The close-out layer is glass-bead preened to densify its surface. This seals and protects the thermal barrier coating system.

  1. 48 CFR 716.306 - [Reserved

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false [Reserved] 716.306 Section 716.306 Federal Acquisition Regulations System AGENCY FOR INTERNATIONAL DEVELOPMENT CONTRACTING METHODS AND CONTRACT TYPES TYPES OF CONTRACTS Cost Reimbursement Contracts 716.306 [Reserved] ...

  2. 48 CFR 716.306 - [Reserved

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 5 2011-10-01 2011-10-01 false [Reserved] 716.306 Section 716.306 Federal Acquisition Regulations System AGENCY FOR INTERNATIONAL DEVELOPMENT CONTRACTING METHODS AND CONTRACT TYPES TYPES OF CONTRACTS Cost Reimbursement Contracts 716.306 [Reserved] ...

  3. Rotary internal combustion engine with integrated supercharged fuel-air induction

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

    Southard, A.A.

    This patent describes an improved method of operating a rotary internal combustion engine of the type wherein a multicusped rotor rotatable upon a rotatable eccentric rotates within a cavity bounded by a wall of lobed trochoidal configuration. The rotor cusps have sealing engagement separating and defining operating chambers in the cavity about the rotor between adjacent pairs of cusps. Such chambers are angularly spaced about and orbit the center of the cavity as the rotor rotates while each chamber alternately expands and contracts in volume. The method comprises cylindrically operating each chamber through a sequence of six phases that aremore » synchronized with three successive increases and decreases in the volume of such chamber, with the first four phases being an internal combustion engine power cycle comprising an air intake phase, a compression phase, a combustion phase and an exhaust phase. The fifth phase comprises inducting air into the chamber, and the sixth phase comprises compressing the inducted air in such chamber and passing such inducted and compressed air through an elongated transfer zone.« less

  4. Treatment to Control Adhesion of Silicone-Based Elastomers

    NASA Technical Reports Server (NTRS)

    deGroh, Henry C., III; Puleo, Bernadette J.; Waters, Deborah L.

    2013-01-01

    Seals are used to facilitate the joining of two items, usually temporarily. At some point in the future, it is expected that the items will need to be separated. This innovation enables control of the adhesive properties of silicone-based elastomers. The innovation may also be effective on elastomers other than the silicone-based ones. A technique has been discovered that decreases the level of adhesion of silicone- based elastomers to negligible levels. The new technique causes less damage to the material compared to alternative adhesion mitigation techniques. Silicone-based elastomers are the only class of rubber-like materials that currently meet NASA s needs for various seal applications. However, silicone-based elastomers have natural inherent adhesive properties. This stickiness can be helpful, but it can frequently cause problems as well, such as when trying to get items apart. In the past, seal adhesion was not always adequately addressed, and has caused in-flight failures where seals were actually pulled from their grooves, preventing subsequent spacecraft docking until the seal was physically removed from the flange via an extravehicular activity (EVA). The primary method used in the past to lower elastomer seal adhesion has been the application of some type of lubricant or grease to the surface of the seal. A newer method uses ultraviolet (UV) radiation a mixture of UV wavelengths in the range of near ultraviolet (NUV) and vacuum ultraviolet (VUV) wavelengths.

  5. Do Differences in Levels, Types, and Duration of Muscle Contraction Have an Effect on the Degree of Post-exercise Depression?

    PubMed

    Miyaguchi, Shota; Kojima, Sho; Kirimoto, Hikari; Tamaki, Hiroyuki; Onishi, Hideaki

    2016-01-01

    We conducted two experiments to determine how differences in muscle contraction levels, muscle contraction types, and movement duration affect degree of post-exercise depression (PED) after non-exhaustive, repetitive finger movement. Twelve healthy participants performed repetitive abduction movements of the right index finger at 2 Hz. In experiment 1, we examined the effects of muscle contraction levels at 10, 20, and 30% maximum voluntary contraction and the effects of muscle contraction types at isotonic and isometric contraction. In experiment 2, we examined the effects of movement duration at 2 and 6 min. Motor-evoked potentials (MEPs) were recorded from the right first dorsal interosseous muscle before movement tasks and 1-10 min after movement tasks. MEP amplitudes after isotonic contraction tasks were significantly smaller than those after isometric contraction tasks and decreased with increasing contraction levels, but were independent of movement duration. This study demonstrated that the degree of PED after non-exhaustive repetitive finger movement depended on muscle contraction levels and types. Thus, the degree of PED may depend on the levels of activity in the motor cortex during a movement task. This knowledge will aid in the design of rehabilitation protocols.

  6. Infrared laser sealing of porcine vascular tissues using a 1,470 nm diode laser: Preliminary in vivo studies.

    PubMed

    Cilip, Christopher M; Kerr, Duane; Latimer, Cassandra A; Rosenbury, Sarah B; Giglio, Nicholas C; Hutchens, Thomas C; Nau, William H; Fried, Nathaniel M

    2017-04-01

    Infrared (IR) lasers are being explored as an alternative to radiofrequency (RF) and ultrasonic (US) devices for rapid hemostasis with minimal collateral zones of thermal damage and tissue necrosis. Previously, a 1,470 nm IR laser sealed and cut ex vivo porcine renal arteries of 1-8 mm diameter in 2 seconds, yielding burst pressures greater than 1,200 mmHg and thermal coagulation zones less than 3 mm. This preliminary study describes in vivo testing of a handheld laser probe in a porcine model. A handheld prototype with vessel/tissue clasping mechanism was tested on 73 blood vessels less than 6 mm diameter using 1,470 nm laser power of 35 W for 1-5 seconds. Device power settings, irradiation time, tissue type, vessel diameter, and histology sample number were recorded for each procedure. The probe was evaluated for hemostasis after sealing isolated and bundled arteriole/venous (A/V) vasculature of porcine abdomen and hind leg. Sealed vessel samples were collected for histological analysis of lateral thermal damage. Hemostasis was achieved in 57 of 73 seals (78%). The probe consistently sealed vasculature in small bowel mesentery, mesometrium, and gastrosplenic and epiploic regions. Seal performance was less consistent on hind leg vasculature including saphenous arteries/bundles and femoral and iliac arteries. Collagen denaturation averaged 1.6 ± 0.9 mm in eight samples excised for histologic examination. A handheld laser probe sealed porcine vessels, in vivo. Further probe development and laser parameter optimization is necessary before infrared lasers may be evaluated as an alternative to RF and US vessel sealing devices. Lasers Surg. Med. 49:366-371, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  7. Integrated fault seal analysis and risk assessemt: Okan and Meren Fields, Nigeria

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

    Eisenberg, R.A.; Brenneman, R.J.; Adepoju, A.A.

    1996-01-01

    Integration of production, geochemical, seismic, well log, and structural data provides important constraints on the sealing capacity and dynamic behavior of fault juxtaposed reservoirs in Okan and Meren fields, offshore Nigeria. Correlations were found between pressure decline histories, juxtaposed fluid types, oil composition, fluid contact relationships, fault sealing/leaking condition, and estimates of the composition of the fault gouge. Fault plane sections defined reservoir juxtapositions and potential cross-fault spill points. Smear gouge ratios calculated from E-logs were used to estimate the composition of fault-gouge materials between juxtaposed reservoirs. These tools augmented interpretation of seal/nonseal character in proved reservoirs and were usedmore » to quantify fault seal risk of untested, fault-dependent closures. In the Okan Field juxtapositions of the G-, H, L-, M, and O-sands were analyzed. Smear gouge ratios correlated to fluid contact relationships and pressure decline histories within these juxtaposed reservoirs empirically calibrate sealing potential. The results of these analyses were then used to interpret production-induced fault seal breakdown within the G-sands and to risk seal integrity of fault-dependent closures within the untested 0-sands in an adjacent, upthrown fault block. Within this fault block the presence of potential fault intersection leak points and large areas of sand/sand juxtaposition with high smear gouge ratios (low sealing potential) limits column heights and potential reserves within the O-sand package. In the Meren Field the E- and G-sands are juxtaposed, on different pressure decline, geochemically distinct, and are characterized by low smear gouge ratios. In contrast, the G- and H-sands, juxtaposed across the same fault, contain similar OOWCs and are characterized by high smear gouge ratios.« less

  8. Integrated fault seal analysis and risk assessemt: Okan and Meren Fields, Nigeria

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

    Eisenberg, R.A.; Brenneman, R.J.; Adepoju, A.A.

    Integration of production, geochemical, seismic, well log, and structural data provides important constraints on the sealing capacity and dynamic behavior of fault juxtaposed reservoirs in Okan and Meren fields, offshore Nigeria. Correlations were found between pressure decline histories, juxtaposed fluid types, oil composition, fluid contact relationships, fault sealing/leaking condition, and estimates of the composition of the fault gouge. Fault plane sections defined reservoir juxtapositions and potential cross-fault spill points. Smear gouge ratios calculated from E-logs were used to estimate the composition of fault-gouge materials between juxtaposed reservoirs. These tools augmented interpretation of seal/nonseal character in proved reservoirs and were usedmore » to quantify fault seal risk of untested, fault-dependent closures. In the Okan Field juxtapositions of the G-, H, L-, M, and O-sands were analyzed. Smear gouge ratios correlated to fluid contact relationships and pressure decline histories within these juxtaposed reservoirs empirically calibrate sealing potential. The results of these analyses were then used to interpret production-induced fault seal breakdown within the G-sands and to risk seal integrity of fault-dependent closures within the untested 0-sands in an adjacent, upthrown fault block. Within this fault block the presence of potential fault intersection leak points and large areas of sand/sand juxtaposition with high smear gouge ratios (low sealing potential) limits column heights and potential reserves within the O-sand package. In the Meren Field the E- and G-sands are juxtaposed, on different pressure decline, geochemically distinct, and are characterized by low smear gouge ratios. In contrast, the G- and H-sands, juxtaposed across the same fault, contain similar OOWCs and are characterized by high smear gouge ratios.« less

  9. 48 CFR 1516.303-72 - Policy.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 6 2012-10-01 2012-10-01 false Policy. 1516.303-72 Section 1516.303-72 Federal Acquisition Regulations System ENVIRONMENTAL PROTECTION AGENCY CONTRACTING METHODS AND CONTRACT TYPES TYPES OF CONTRACTS Cost-Reimbursement Contracts 1516.303-72 Policy. (a) The...

  10. 48 CFR 1516.303-72 - Policy.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 6 2014-10-01 2014-10-01 false Policy. 1516.303-72 Section 1516.303-72 Federal Acquisition Regulations System ENVIRONMENTAL PROTECTION AGENCY CONTRACTING METHODS AND CONTRACT TYPES TYPES OF CONTRACTS Cost-Reimbursement Contracts 1516.303-72 Policy. (a) The...

  11. 48 CFR 1016.505 - Ordering.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 5 2011-10-01 2011-10-01 false Ordering. 1016.505 Section 1016.505 Federal Acquisition Regulations System DEPARTMENT OF THE TREASURY CONTRACTING METHODS AND CONTRACT TYPES TYPES OF CONTRACTS Indefinite-Delivery Contracts 1016.505 Ordering. (b)(6) Bureaus shall...

  12. Cryogenic Flange and Seal Evaluation

    NASA Technical Reports Server (NTRS)

    Ramirez, Adrian

    2014-01-01

    The assembly of flanges, seals, and pipes are used to carry cryogenic fluid from a storage tank to the vehicle at launch sites. However, after a certain amount of cycles these raised face flanges with glass-filled Teflon gaskets have been found to have torque relaxation and are as a result susceptible to cryogenic fluid leakage if not re-torqued. The intent of this project is to identify alternate combinations of flanges and seals which may improve thermal cycle performance and decrease re-torque requirements. The general approach is to design a test fixture to evaluate leak characteristics between spiral and concentric serrations and to test alternate flange and seal combinations. Due to insufficient time, it was not possible to evaluate these different types of combinations for the combination that improved thermal cycle performance the most. However, the necessary drawings for the test fixture were designed and assembled along with the collection of the necessary parts.

  13. Characteristics of Physical Training Activities of West Coast U.S. Navy Sea-Air-Land Personnel (SEALS)

    DTIC Science & Technology

    1992-11-01

    REPETITIONS, OR LOADS VARY. USE TIHE AVERAGE FOR YOUR RESPONSE TO THIESE QUESTIONS Body Weight: _ pounds I Repetition Average Exercise Maximum Sets...Sea, Air, Land (SEAL) personnel undergoing advanced training. Responses to this questionnaire provided information on the types, frequencies, and...their responses were used to characterize training activity according to the American College of Sports Medicine guidelines for maintenance of aerobic

  14. Hayabusa2 Sample Catcher and Container: Metal-Seal System for Vacuum Encapsulation of Returned Samples with Volatiles and Organic Compounds Recovered from C-Type Asteroid Ryugu

    NASA Astrophysics Data System (ADS)

    Okazaki, Ryuji; Sawada, Hirotaka; Yamanouchi, Shinji; Tachibana, Shogo; Miura, Yayoi N.; Sakamoto, Kanako; Takano, Yoshinori; Abe, Masanao; Itoh, Shoichi; Yamada, Keita; Yabuta, Hikaru; Okamoto, Chisato; Yano, Hajime; Noguchi, Takaaki; Nakamura, Tomoki; Nagao, Keisuke

    2017-07-01

    The spacecraft Hayabusa2 was launched on December 3, 2014, to collect and return samples from a C-type asteroid, 162173 Ryugu (provisional designation, 1999 JU3). It is expected that the samples collected contain organic matter and water-bearing minerals and have key information to elucidate the origin and history of the Solar System and the evolution of bio-related organics prior to delivery to the early Earth. In order to obtain samples with volatile species without terrestrial contamination, based on lessons learned from the Hayabusa mission, the sample catcher and container of Hayabusa2 were refined from those used in Hayabusa. The improvements include (1) a mirror finish of the inner wall surface of the sample catcher and the container, (2) adoption of an aluminum metal sealing system, and (3) addition of a gas-sampling interface for gas collection and evacuation. The former two improvements were made to limit contamination of the samples by terrestrial atmosphere below 1 Pa after the container is sealed. The gas-sampling interface will be used to promptly collect volatile species released from the samples in the sample container after sealing of the container. These improvements maintain the value of the returned samples.

  15. First longitudinal study of seal-feeding killer whales (Orcinus orca) in Norwegian coastal waters.

    PubMed

    Jourdain, Eve; Vongraven, Dag; Bisther, Anna; Karoliussen, Richard

    2017-01-01

    Killer whales (Orcinus orca) have been documented preying on either fish or marine mammals in several regions, suggesting that this odontocete species has the ability to specialize on different types of prey. Off Norway, killer whales have been shown to rely on the Atlantic herring (Clupea harengus) as a main prey resource. Infrequent observations have revealed seals as an additional component of their diet, yet the extent of predation on marine mammals has remained largely unknown. Here, we present the findings of 29 years of photographic and observational data on seal-feeding killer whale groups identified in Norwegian coastal waters. Four groups have been observed preying and feeding on seals over several years, taking both harbor (Phoca vitulina) and grey (Halichoerus grypus) seals. These stable groups are shown to adopt small group sizes, were typically observed in near-shore areas and were not encountered on herring wintering grounds. Behavioral and social traits adopted by these groups are similar to those of pinniped-feeding killer whales from other regions. The potential ecological reasons and the extent of such prey specializations are discussed.

  16. First longitudinal study of seal-feeding killer whales (Orcinus orca) in Norwegian coastal waters

    PubMed Central

    Bisther, Anna; Karoliussen, Richard

    2017-01-01

    Killer whales (Orcinus orca) have been documented preying on either fish or marine mammals in several regions, suggesting that this odontocete species has the ability to specialize on different types of prey. Off Norway, killer whales have been shown to rely on the Atlantic herring (Clupea harengus) as a main prey resource. Infrequent observations have revealed seals as an additional component of their diet, yet the extent of predation on marine mammals has remained largely unknown. Here, we present the findings of 29 years of photographic and observational data on seal-feeding killer whale groups identified in Norwegian coastal waters. Four groups have been observed preying and feeding on seals over several years, taking both harbor (Phoca vitulina) and grey (Halichoerus grypus) seals. These stable groups are shown to adopt small group sizes, were typically observed in near-shore areas and were not encountered on herring wintering grounds. Behavioral and social traits adopted by these groups are similar to those of pinniped-feeding killer whales from other regions. The potential ecological reasons and the extent of such prey specializations are discussed. PMID:28666015

  17. 48 CFR 50.103-2 - Types of contract adjustment.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... contract; for example, when a person, responding to an agency official's written or oral instructions and... 48 Federal Acquisition Regulations System 1 2011-10-01 2011-10-01 false Types of contract... CONTRACT MANAGEMENT EXTRAORDINARY CONTRACTUAL ACTIONS AND THE SAFETY ACT Extraordinary Contractual Actions...

  18. 48 CFR 50.103-2 - Types of contract adjustment.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... contract; for example, when a person, responding to an agency official's written or oral instructions and... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Types of contract... CONTRACT MANAGEMENT EXTRAORDINARY CONTRACTUAL ACTIONS AND THE SAFETY ACT Extraordinary Contractual Actions...

  19. 48 CFR 16.402-2 - Performance incentives.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 1 2012-10-01 2012-10-01 false Performance incentives. 16... CONTRACTING METHODS AND CONTRACT TYPES TYPES OF CONTRACTS Incentive Contracts 16.402-2 Performance incentives. (a) Performance incentives may be considered in connection with specific product characteristics (e.g...

  20. 48 CFR 16.402-2 - Performance incentives.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 1 2014-10-01 2014-10-01 false Performance incentives. 16... CONTRACTING METHODS AND CONTRACT TYPES TYPES OF CONTRACTS Incentive Contracts 16.402-2 Performance incentives. (a) Performance incentives may be considered in connection with specific product characteristics (e.g...

  1. 48 CFR 16.402-2 - Performance incentives.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 1 2011-10-01 2011-10-01 false Performance incentives. 16... CONTRACTING METHODS AND CONTRACT TYPES TYPES OF CONTRACTS Incentive Contracts 16.402-2 Performance incentives. (a) Performance incentives may be considered in connection with specific product characteristics (e.g...

  2. 48 CFR 15.605 - Content of unsolicited proposals.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... CONTRACTING METHODS AND CONTRACT TYPES CONTRACTING BY NEGOTIATION Unsolicited Proposals 15.605 Content of... and type of organization; e.g., profit, nonprofit, educational, small business; (2) Names and..., including alternates; and (4) Type of support needed from the agency; e.g., Government property or personnel...

  3. 29 CFR 1926.14 - Federal contract for “mixed” types of performance.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Interpretations § 1926.14 Federal contract for “mixed” types of performance. (a) It is the intent of the Congress... that when a Federal contract calls for mixed types of performance, such as both manufacturing and... the mixed types of performances include both construction and manufacturing, see also § 1926.15(b...

  4. 29 CFR 1926.14 - Federal contract for “mixed” types of performance.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Interpretations § 1926.14 Federal contract for “mixed” types of performance. (a) It is the intent of the Congress... that when a Federal contract calls for mixed types of performance, such as both manufacturing and... the mixed types of performances include both construction and manufacturing, see also § 1926.15(b...

  5. 29 CFR 1926.14 - Federal contract for “mixed” types of performance.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Interpretations § 1926.14 Federal contract for “mixed” types of performance. (a) It is the intent of the Congress... that when a Federal contract calls for mixed types of performance, such as both manufacturing and... the mixed types of performances include both construction and manufacturing, see also § 1926.15(b...

  6. Design of a factorial experiment with randomization restrictions to assess medical device performance on vascular tissue

    PubMed Central

    2011-01-01

    Background Energy-based surgical scalpels are designed to efficiently transect and seal blood vessels using thermal energy to promote protein denaturation and coagulation. Assessment and design improvement of ultrasonic scalpel performance relies on both in vivo and ex vivo testing. The objective of this work was to design and implement a robust, experimental test matrix with randomization restrictions and predictive statistical power, which allowed for identification of those experimental variables that may affect the quality of the seal obtained ex vivo. Methods The design of the experiment included three factors: temperature (two levels); the type of solution used to perfuse the artery during transection (three types); and artery type (two types) resulting in a total of twelve possible treatment combinations. Burst pressures of porcine carotid and renal arteries sealed ex vivo were assigned as the response variable. Results The experimental test matrix was designed and carried out as a split-plot experiment in order to assess the contributions of several variables and their interactions while accounting for randomization restrictions present in the experimental setup. The statistical software package SAS was utilized and PROC MIXED was used to account for the randomization restrictions in the split-plot design. The combination of temperature, solution, and vessel type had a statistically significant impact on seal quality. Conclusions The design and implementation of a split-plot experimental test-matrix provided a mechanism for addressing the existing technical randomization restrictions of ex vivo ultrasonic scalpel performance testing, while preserving the ability to examine the potential effects of independent factors or variables. This method for generating the experimental design and the statistical analyses of the resulting data are adaptable to a wide variety of experimental problems involving large-scale tissue-based studies of medical or experimental device efficacy and performance. PMID:21599963

  7. Soil seal development under simulated rainfall: Structural, physical and hydrological dynamics

    NASA Astrophysics Data System (ADS)

    Armenise, Elena; Simmons, Robert W.; Ahn, Sujung; Garbout, Amin; Doerr, Stefan H.; Mooney, Sacha J.; Sturrock, Craig J.; Ritz, Karl

    2018-01-01

    This study delivers new insights into rainfall-induced seal formation through a novel approach in the use of X-ray Computed Tomography (CT). Up to now seal and crust thickness have been directly quantified mainly through visual examination of sealed/crusted surfaces, and there has been no quantitative method to estimate this important property. X-ray CT images were quantitatively analysed to derive formal measures of seal and crust thickness. A factorial experiment was established in the laboratory using open-topped microcosms packed with soil. The factors investigated were soil type (three soils: silty clay loam - ZCL, sandy silt loam - SZL, sandy loam - SL) and rainfall duration (2-14 min). Surface seal formation was induced by applying artificial rainfall events, characterised by variable duration, but constant kinetic energy, intensity, and raindrop size distribution. Soil porosities derived from CT scans were used to quantify the thickness of the rainfall-induced surface seals and reveal temporal seal micro-morphological variations with increasing rainfall duration. In addition, the water repellency and infiltration dynamics of the developing seals were investigated by measuring water drop penetration time (WDPT) and unsaturated hydraulic conductivity (Kun). The range of seal thicknesses detected varied from 0.6 to 5.4 mm. Soil textural characteristics and OM content played a central role in the development of rainfall-induced seals, with coarser soil particles and lower OM content resulting in thicker seals. Two different trends in soil porosity vs. depth were identified: i) for SL soil porosity was lowest at the immediate soil surface, it then increased constantly with depth till the median porosity of undisturbed soil was equalled; ii) for ZCL and SL the highest reduction in porosity, as compared to the median porosity of undisturbed soil, was observed in a well-defined zone of maximum porosity reduction c. 0.24-0.48 mm below the soil surface. This contrasting behaviour was related to different dynamics and processes of seal formation which depended on the soil properties. The impact of rainfall-induced surface sealing on the hydrological behaviour of soil (as represented by WDTP and Kun) was rapid and substantial: an average 60% reduction in Kun occurred for all soils between 2 and 9 min rainfall, and water repellent surfaces were identified for SZL and ZCL. This highlights that the condition of the immediate surface of agricultural soils involving rainfall-induced structural seals has a strong impact in the overall ability of soil to function as water reservoir.

  8. Investigation of the effect of sealed surfaces on local climate in urban areas

    NASA Astrophysics Data System (ADS)

    Weihs, Philipp; Hasel, Stefan; Mursch-Radlgruber, Erich; Gützer, Christian; Krispel, Stefan; Peyerl, Martin; Trimmel, Heidi

    2015-04-01

    Local climate is driven by the interaction between energy balance and energy transported by advected air. Short-wave and long-wave radiation are major components in this interaction. Some few studies (e.g. Santamouris et al.) showed that adjusting the grade of reflection of surfaces is an efficient way to influence temperature. The present study investigates the influence of high albedo concrete surfaces on local climate. The first step of the study consisted of experimental investigations: routine measurements of the short and longwave radiation balance, of the ground and of the air temperature and humidity at different heights above 6 different types of sealed surfaces were performed. During this measurement campaign the above mentioned components were measured over a duration of 4 months above two conventional asphalt surfaces, one conventional concrete and three newly developed concrete surfaces with increased reflectances. Measured albedo values amounted to 0.12±0.02 for the asphalt surfaces and to maximum values of 0.56 for high albedo concrete. The maximum difference in surface temperature between the asphalt surfaces and the high albedo concrete surfaces amounted to 15°C. In addition the emission constants of the different sealed surfaces were also determined and were compared to values from literature.. In a second step the urban energy balance model Envi_Met was used to simulate the surface temperature of the six surfaces. The simulated surface temperatures were compared to the measured surface temperatures and statements as to uncertainties of the model simulations were made In a third step, Envi_Met was used to simulate the local climate of an urban district in Vienna. The surface and air temperature and the SW, LW fluxes were calculated for different types of sealed surfaces. By performing calculations of thermal stress indices (UTCI, PMV), statements as to the influence of the type of sealed surface on thermal stress on humans was made.

  9. Safety assessment methodology in management of spent sealed sources.

    PubMed

    Mahmoud, Narmine Salah

    2005-02-14

    Environmental hazards can be caused from radioactive waste after their disposal. It was therefore important that safety assessment methodologies be developed and established to study and estimate the possible hazards, and institute certain safety methodologies that lead and prevent the evolution of these hazards. Spent sealed sources are specific type of radioactive waste. According to IAEA definition, spent sealed sources are unused sources because of activity decay, damage, misuse, loss, or theft. Accidental exposure of humans from spent sealed sources can occur at the moment they become spent and before their disposal. Because of that reason, safety assessment methodologies were tailored to suit the management of spent sealed sources. To provide understanding and confidence of this study, validation analysis was undertaken by considering the scenario of an accident that occurred in Egypt, June 2000 (the Meet-Halfa accident from an iridium-192 source). The text of this work includes consideration related to the safety assessment approaches of spent sealed sources which constitutes assessment context, processes leading an active source to be spent, accident scenarios, mathematical models for dose calculations, and radiological consequences and regulatory criteria. The text also includes a validation study, which was carried out by evaluating a theoretical scenario compared to the real scenario of Meet-Halfa accident depending on the clinical assessment of affected individuals.

  10. 48 CFR 216.401-70 - Data collection.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 3 2013-10-01 2013-10-01 false Data collection. 216.401..., DEPARTMENT OF DEFENSE CONTRACTING METHODS AND CONTRACT TYPES TYPES OF CONTRACTS Incentive Contracts 216.401-70 Data collection. Section 814 of the National Defense Authorization Act for Fiscal Year 2007 (Pub...

  11. 48 CFR 216.401-70 - Data collection.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 3 2012-10-01 2012-10-01 false Data collection. 216.401..., DEPARTMENT OF DEFENSE CONTRACTING METHODS AND CONTRACT TYPES TYPES OF CONTRACTS Incentive Contracts 216.401-70 Data collection. Section 814 of the National Defense Authorization Act for Fiscal Year 2007 (Pub...

  12. 48 CFR 216.401-70 - Data collection.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 3 2014-10-01 2014-10-01 false Data collection. 216.401..., DEPARTMENT OF DEFENSE CONTRACTING METHODS AND CONTRACT TYPES TYPES OF CONTRACTS Incentive Contracts 216.401-70 Data collection. Section 814 of the National Defense Authorization Act for Fiscal Year 2007 (Pub...

  13. High temperature lubricant screening and systems studies

    NASA Technical Reports Server (NTRS)

    Jones, D. A.

    1973-01-01

    Four candidate lubricants for next generation aircraft gas turbine application were tested under open atmosphere conditions in a rig simulating an advanced engine 125 mm bore mainshaft thrust bearing position. Testing was conducted at speeds to 24,000 rpm (3,000,000 bearing DN), bearing ring temperature of 500 F, and with 1200 F air and 100 psi differential pressure across the seals installed in a dual tandem arrangement. Test bearing was a 125 mm bore split inner ring, outer race riding angular contact ball bearing under a 3280 lb. thrust load. One lubricant, a type 2 ester, performed extremely well. The mainshaft seal limited the performance. Numerous design improvements for this seal were indicated.

  14. Toxoplasmosis in a Hawaiian monk seal (Monachus schauinslandi).

    PubMed

    Honnold, Shelley P; Braun, Robert; Scott, Dana P; Sreekumar, C; Dubey, J P

    2005-06-01

    Toxoplasma gondii infection in marine mammals is intriguing and indicative of contamination of the ocean environment with oocysts. T. gondii was identified in a Hawaiian monk seal (Monachus schauinslandi) that had visceral and cerebral lesions. Tachyzoites were found in the lymph nodes, spleen, diaphragm, heart, adrenal glands, and brain. A few tissue cysts were found in sections of the cerebrum. The diagnosis was confirmed serologically, by immunohistochemical staining with T. gondii-specific polyclonal rabbit serum, and by the detection of T. gondii DNA. The genotype was determined to be type III by restriction fragment length polymorphisms of the SAG2 gene. This is the first report of T. gondii infection in a Hawaiian monk seal.

  15. Performance degradation of ferrofluidic feedthroughs in a mixed irradiation field

    DOE PAGES

    Simos, Nikolaos; Fernandes, S.; Mittig, Wolfgang; ...

    2016-10-06

    We present ferrofluidic feedthrough (FF) rotary seals containing either NdFeB or SmCo-type permanent magnets that have been considered for use in the target and beam dump systems of the Facility for Rare Isotope Beams (FRIB). To evaluate their performance under irradiation three FF seals were irradiated in a mixed field consisting of fast neutrons, protons and γ-rays to an average absorbed dose of 0.2, 2.0, and 20.0 MGy at the Brookhaven Linac Isotope Producer facility (BLIP). The radiation types and energy profiles mimic those expected at the FRIB facility. Degradation of the operational performance of these devices due to irradiationmore » is expected to be the result of the de-magnetization of the permanent magnets contained within the seal and the changes in the ferrofluid properties. Post-irradiation performance was evaluated by determining the ferrofluidic seal vacuum tightness and torque under static and dynamic conditions. The study revealed that the ferrofluidic feedthrough seal irradiated to a dose of 0.2 MGy maintained its vacuum tightness under both static and rotational condition while the one irradiated to a dose of 2.0 MGy exhibited signs of ferrofluid damage but no overall performance loss. Lastly, at 20 MGy dose the effects of irradiation on the ferrofluid properties (viscosity and particle agglomeration) were shown to be severe. Furthermore, limited de-magnetization of the annular shaped Nd 2Fe 14B and Sm 2Co 17 magnets located within the irradiated FFs was observed for doses of 0.2 MGy and 20 MGy respectively.« less

  16. Effects of fault-controlled CO2 alteration on mineralogical and geomechanical properties of reservoir and seal rocks, Crystal Geyser, Green River, Utah

    NASA Astrophysics Data System (ADS)

    Major, J. R.; Eichhubl, P.; Urquhart, A.; Dewers, T. A.

    2012-12-01

    An understanding of the coupled chemical and mechanical properties of reservoir and seal units undergoing CO2 injection is critical for modeling reservoir behavior in response to the introduction of CO2. The implementation of CO2 sequestration as a mitigation strategy for climate change requires extensive risk assessment that relies heavily on computer models of subsurface reservoirs. Numerical models are fundamentally limited by the quality and validity of their input parameters. Existing models generally lack constraints on diagenesis, failing to account for the coupled geochemical or geomechanical processes that affect reservoir and seal unit properties during and after CO2 injection. For example, carbonate dissolution or precipitation after injection of CO2 into subsurface brines may significantly alter the geomechanical properties of reservoir and seal units and thus lead to solution-enhancement or self-sealing of fractures. Acidified brines may erode and breach sealing units. In addition, subcritical fracture growth enhanced by the presence of CO2 could ultimately compromise the integrity of sealing units, or enhance permeability and porosity of the reservoir itself. Such unknown responses to the introduction of CO2 can be addressed by laboratory and field-based observations and measurements. Studies of natural analogs like Crystal Geyser, Utah are thus a critical part of CO2 sequestration research. The Little Grand Wash and Salt Wash fault systems near Green River, Utah, host many fossil and active CO2 seeps, including Crystal Geyser, serving as a faulted anticline CO2 reservoir analog. The site has been extensively studied for sequestration and reservoir applications, but less attention has been paid to the diagenetic and geomechanical aspects of the fault zone. XRD analysis of reservoir and sealing rocks collected along transects across the Little Grand Wash Fault reveal mineralogical trends in the Summerville Fm (a siltstone seal unit) with calcite and smectite increasing toward to the fault, whereas illite decreases. These trends are likely the result of CO2-related diagenesis, and similar trends are also observed in sandstone units at the site. Fracture mechanics testing of unaltered and CO2-altered sandstone and siltstone samples shows that CO2-related diagenesis, which is indicated by bleaching of the Entrada Fm, has significantly decreased the fracture resistance. The subcritical fracture index is similarly affected by alteration. These compositional and mechanical changes are expected to affect the extent, geometry, and flow properties of fracture networks in CO2 sequestration systems, and thus may significantly affect reservoir and seal performance in CO2 reservoirs. This work was funded in part by the Center for Frontiers of Subsurface Energy Security, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Award Number DE-SC0001114. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

  17. 48 CFR 1516.303-75 - Amount of cost-sharing.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    .... 1516.303-75 Section 1516.303-75 Federal Acquisition Regulations System ENVIRONMENTAL PROTECTION AGENCY CONTRACTING METHODS AND CONTRACT TYPES TYPES OF CONTRACTS Cost-Reimbursement Contracts 1516.303-75 Amount of... market share position; (3) The time and risk necessary to achieve success; (4) If the results of the...

  18. MH-60R Multi-Mission Helicopter (MH-60R)

    DTIC Science & Technology

    2016-03-23

    1087 Contract Number: N00019-11-C-0077 Contract Type: Firm Fixed Price (FFP) Award Date: September 27, 2011 Definitization Date: September 27...02871- 1087 Contract Number: N00019-13-C-0012 Contract Type: Firm Fixed Price (FFP) Award Date: December 20, 2012 Definitization Date: December 20

  19. 48 CFR 315.371 - Contract preparation and award.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... CONTRACTING METHODS AND CONTRACT TYPES CONTRACTING BY NEGOTIATION Source Selection 315.371 Contract... the contract until the finance office certifies that the funds are available for obligation. ...

  20. 40 CFR 35.937-1 - Type of contract (subagreement).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 1 2011-07-01 2011-07-01 false Type of contract (subagreement). 35.937-1 Section 35.937-1 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY GRANTS AND OTHER... § 35.937-1 Type of contract (subagreement). (a) General. Cost-plus-percentage-of-cost and percentage-of...

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