WorldWideScience

Sample records for foil face seal

  1. Foil Face Seal Testing

    Science.gov (United States)

    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.

  2. Design considerations for mechanical face seals

    Science.gov (United States)

    Ludwig, L. P.; Greiner, H. F.

    1980-01-01

    Two companion reports deal with design considerations for improving performance of mechanical face seals, one of family of devices used in general area of fluid sealing of rotating shafts. One report deals with basic seal configuration and other with lubrication of seal.

  3. Dynamic Instability of Undamped Bellows Face Seals in Cryogenic Liquid

    National Research Council Canada - National Science Library

    Hudelson, John C

    1966-01-01

    .... The results of the tests indicated that dynamic instability will occur in undamped bellows face seals operating in a cryogenic environment and be of such a magnitude as to damage the sealing surface...

  4. Computer tools for face seal analyses developed at John Crane

    Science.gov (United States)

    Wu, Shifeng

    1994-01-01

    The purposes of the computer tools for face seal analysis are new product optimization, existing seals on new applications, existing seals on off-duty conditions, and trouble-shooting. Discussed in this viewgraph presentation are interface forces, friction/heat generation, heat transfer/temperature distribution, axisymmetric pressure/thermal distortion, leakage, and an example case.

  5. Enclosed mechanical seal face design for brittle materials copyright

    International Nuclear Information System (INIS)

    Marsi, J.A.

    1994-01-01

    Metal carbides are widely used as seal face material due to their hardness and wear resistance. Silicon carbide (SiC) has excellent performance as a seal face material, but it is relatively brittle and may break due to accidental overloads outside the boundary of normal operating conditions. In mechanical seals for nuclear primary coolant pumps, the shattered SiC pieces can get into the reactor system and cause serious damage. The conventional method of containing an SiC seal face is to shrink-fit it in a holder, which may lead the seal designer to contend with unwanted seal face deflections. This paper presents a successful, tested design which does not rely on shrink-fits. 5 refs., 9 figs., 4 tabs

  6. Development of Advanced Carbon Face Seals for Aircraft Engines

    Science.gov (United States)

    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.

  7. Design and development of face seal type sealing plug for advanced heavy water reactor

    International Nuclear Information System (INIS)

    Bansal, S.; Bhattacharyya, S.; Patel, R.J.; Agrawal, R.G.; Vaze, K.K.

    2005-09-01

    Advanced Heavy Water Reactor is a vertical pressure tube type reactor having light water as its coolant and heavy water as moderator. Sealing plug is required to close the pressure boundary of main heat transport system of the reactor by preventing escape of light water/steam From the coolant channel. There are 452 coolant channels in the reactor located in square lattice pitch. Sealing plug is located at the top of each coolant channel (in the top end fitting). Top end fitting is having a stepped bore to create a sealing face. Sealing plug is held through its expanded jaws in a specially provided groove of the end fitting. The plug was designed and prototypes were manufactured considering its functional importance, intricate design and precision machining requirements. Sealing plug consists of about 20 components mostly made up of precipitation hardening stainless steel, which is suitable for water environment and meets other requirements of strength and resistance to wear and galling. Seal disc is a critical component of the sealing plug as it is the pressure-retaining component. It is a circular disc with protruded stem. One face of the seal disc is nickel plated in the peripheral area that creates the sealing by abutting against the sealing face provided in the end fitting. The typical shape and profile of seal disc provides flexibility and allows elastic deformation to assist in locking of sealing plug and creating adequate seating force for effective sealing. Design and development aspects of the sealing plug have been detailed out in this report. Also results of stress analysis and experimental studies for seal disc have been mentioned in the report. Stress analysis and experimental testing was required for the seal disc because high stresses are developed due to its exposure to high pressure and temperature environment of Main Heat Transport system. Hot testing was carried out to simulate the reactor-simulated condition. The performance was found to be

  8. Dynamics of face seals for high speed turbomachinery

    Science.gov (United States)

    Leefe, Simon

    1993-10-01

    Face seals in rocket engine fuel and oxidizer turbopumps have been the subject of intense investigation for over 25 years. While advances have been made in the understanding of thin film lubrication between seal faces, valuable data has been produced on the friction and wear of material pairs in cryogenic environments; pioneering work has been done on the effect of lubricant phase change in seals, and many improvements have been made in mechanical seal design. Relatively superficial attention has been given to the vibrational dynamics of face seals in high-speed turbomachinery. BHR Group Ltd. (formerly BHRA) has recently completed the first stage of a study, commissioned by the European Space Agency, to investigate this area. This has involved the development of a two-dimensional adiabatic, turbulent lubrication model for thick gas film applications, the production of an integrated mathematical model of gas seal vibrational dynamics for thin film applications, implementation in software, the undertaking of an experimental program to validate software against variations in operating conditions and design variables, and suggestions for improved seal design.

  9. Application of the Wavy Mechanical Face Seal to Submarine Seal Design.

    Science.gov (United States)

    1982-07-01

    Entered) The nine-wave seal has been shown to operate satisfactorily in preliminary testing. Problems with fabrication, stiffness, bonding, and oil sistem ...mechanical pressure. If the fluid pressure at the faces is large enough to support all of the load, then there will be no contact and no adhesive wear.* If...is a Pure Carbon P658RC material which is epoxied into the -.ine-wave seal using 3M 1838 B/A adhesive . It should be pointed out at this time that

  10. Influence analysis of secondary O-ring seals in dynamic behavior of spiral groove gas face seals

    Science.gov (United States)

    Hu, Songtao; Huang, Weifeng; Liu, Xiangfeng; Wang, Yuming

    2016-05-01

    The current research on secondary O-ring seals used in mechanical seals has begun to focus on their dynamic properties. However, detailed analysis of the dynamic properties of O-ring seals in spiral groove gas face seals is lacking. In particular a transient study and a difference analysis of steady-state and transient performance are imperative. In this paper, a case study is performed to gauge the effect of secondary O-ring seals on the dynamic behavior (steady-state performance and transient performance) of face seals. A numerical finite element method (FEM) model is developed for the dynamic analysis of spiral groove gas face seals with a flexibly mounted stator in the axial and angular modes. The rotor tilt angle, static stator tilt angle and O-ring damping are selected to investigate the effect of O-ring seals on face seals during stable running operation. The results show that the angular factor can be ignored to save time in the simulation under small damping or undamped conditions. However, large O-ring damping has an enormous effect on the angular phase difference of mated rings, affecting the steady-state performance of face seals and largely increasing the possibility of face contact that reduces the service life of face seals. A pressure drop fluctuation is carried out to analyze the effect of O-ring seals on the transient performance of face seals. The results show that face seals could remain stable without support stiffness and O-ring damping during normal stable operation but may enter a large-leakage state when confronting instantaneous fluctuations. The oscillation-amplitude shortening effect of O-ring damping on the axial mode is much greater than that on the angular modes and O-ring damping prefers to cater for axial motion at the cost of angular motion. This research proposes a detailed dynamic-property study of O-ring seals in spiral groove gas face seals, to assist in the design of face seals.

  11. End face seals in high pressure water - learning from those failures

    International Nuclear Information System (INIS)

    Metcalfe, R.

    1976-08-01

    End face seals are complex devices which are used widely in shaft sealing of rotating equipment. In the nuclear industry, working at the limits of present sealing technlogy with a massive economic dependence on reliability, the importance of scrutinizing seal failures and thereby attempting to prevent premature failures from recurring was fully realized. This paper describes Canadian nuclear sealing experience. Failed seal data is presented; practical examples are categorized as to cause and type. (author)

  12. Design considerations in mechanical face seals for improved performance. I - Basic configurations

    Science.gov (United States)

    Ludwig, L. P.; Greiner, H. F.

    1977-01-01

    Basic assembly configurations of the mechanical face seal are described and some advantages associated with each are listed. The various forms of seal components (the primary seal, secondary seal, etc.) are illustrated, and functions pointed out. The technique of seal pressure balancing and its application is described; and the concept of the PV factor, its different forms and limitations are discussed. Brief attention is given to seal lubrication since it is covered in detail in a companion paper. Finally, the operating conditions for various applications of low pressure seals (aircraft transmissions) are listed, and the seal failure mode of a particular application is discussed.

  13. Design considerations in mechanical face seals for improved performance. 1: Basic configurations

    Science.gov (United States)

    Ludwig, L. P.; Greiner, H. F.

    1977-01-01

    Basic assembly configurations of the mechanical face seal are described and some advantages associated with each are listed. The various forms of seal components are illustrated, and functions pointed out. The technique of seal pressure balancing and its application are described; and the concept of the PV factor, its different forms and limitations are discussed. Brief attention is given to seal lubrication since it is covered in detail in a companion paper. Finally, the operating conditions for various applications of low pressure seals (aircraft transmissions) are listed, and the seal failure mode of a particular application is discussed.

  14. Design considerations in mechanical face seals for improved performance. 2: Lubrication

    Science.gov (United States)

    Ludwig, L. P.; Greiner, H. F.

    1977-01-01

    The importance of sealing technology in our industrial, chemical-oriented society in regard to maintenance and environmental contamination is pointed out. It is stated that seal performance (leakage, life) is directly related to seal lubrication. Current thinking in regard to seal lubrication is reviewed; the effect of energy dissipation in the thin lubricating film separating the sealing faces is pointed out, and the results of vaporization due to heating are illustrated. Also, hydrodynamic lubrication is reviewed, and an inherent tendency for the seal to operate with angular misalignment is shown. Recent work on hydrostatic effects is summarized and the conditions for seal instability are discussed. Four different modes of seal lubrication are postulated with the mode type being a strong function of speed and pressure.

  15. Design considerations in mechanical face seals for improved performance. II - Lubrication

    Science.gov (United States)

    Ludwig, L. P.; Greiner, H. F.

    1977-01-01

    The importance of sealing technology in the U.S. industrial chemical-orientated society in regard to maintenance and environmental contamination is pointed out. It is stated that seal performance (leakage, life) is directly related to seal lubrication, which is a mechanism not well understood. Current thinking in regard to seal lubrication is reviewed, the effect of energy dissipation in the thin lubricating film separating the sealing faces is pointed out, and the results of vaporization due to heating are illustrated. Also, hydrodynamic lubrication is reviewed, and an inherent tendency for the seal to operate with angular misalignment is pointed out. Recent work on hydrostatic effects is summarized and the conditions for seal instability are discussed. Four different modes of seal lubrication are postulated with the mode type being a strong function of speed and pressure.

  16. SOME CONSIDERATIONS REGARDING ANALITICAL SOLVING OF THE REYNOLD’S EQUATION FROM FACE SEAL

    Directory of Open Access Journals (Sweden)

    Nicolae POPA

    2010-10-01

    Full Text Available Taking into consideration a mechanical face seal which runs in hydrodynamic duty, we intend to understand what’s going on under its surfaces. Until nowadays the experimental study to measure the parameters of film between two seal surfaces is very difficult. To explain these phenomena from this interface is necessary to know the theoretical pressures. The paper uses a primary seal model where the seal surfaces are considered with misalignment but the ring centre distance is constant. Considering some simplified hypothesis it determines the Reynold’s equation, it’s solving leading to the pressure equation of sealing interface.

  17. Thermal fluid-solid interaction model and experimental validation for hydrostatic mechanical face seals

    Science.gov (United States)

    Huang, Weifeng; Liao, Chuanjun; Liu, Xiangfeng; Suo, Shuangfu; Liu, Ying; Wang, Yuming

    2014-09-01

    Hydrostatic mechanical face seals for reactor coolant pumps are very important for the safety and reliability of pressurized-water reactor power plants. More accurate models on the operating mechanism of the seals are needed to help improve their performance. The thermal fluid-solid interaction (TFSI) mechanism of the hydrostatic seal is investigated in this study. Numerical models of the flow field and seal assembly are developed. Based on the mechanism for the continuity condition of the physical quantities at the fluid-solid interface, an on-line numerical TFSI model for the hydrostatic mechanical seal is proposed using an iterative coupling method. Dynamic mesh technology is adopted to adapt to the changing boundary shape. Experiments were performed on a test rig using a full-size test seal to obtain the leakage rate as a function of the differential pressure. The effectiveness and accuracy of the TFSI model were verified by comparing the simulation results and experimental data. Using the TFSI model, the behavior of the seal is presented, including mechanical and thermal deformation, and the temperature field. The influences of the rotating speed and differential pressure of the sealing device on the temperature field, which occur widely in the actual use of the seal, are studied. This research proposes an on-line and assembly-based TFSI model for hydrostatic mechanical face seals, and the model is validated by full-sized experiments.

  18. Experimental research on friction factor of end faces of contacting mechanical seals

    Science.gov (United States)

    Wei, Long; Gu, Bo-qin; Feng, Xiu; Sun, Jian-jun

    2008-11-01

    The friction of the seal faces is the most important phenomenon in working process of contacting mechanical seals. The friction factor f is a key parameter for expressing the friction regime of the seal faces, the frictional power, the wearing capacity, the friction heat productivity, the temperature distortion of the end face and the temperature of the end face. The relationship between the friction factor f and the friction regime of the end faces of contacting mechanical seals was discussed from a microscopic point of view. The friction factor is usually worked out by the friction torque which is measured in the test. In the computer aided testing device of the mechanical seal system, the experimental investigations on the basic performance of the B104a-70 contacting mechanical seal was carried out. The test results indicate that the bigger the spring pressure of B104a-70 contacting mechanical seal, the bigger the friction factor. When the spring pressure is less, the bigger the rotational speed, the bigger the friction factor. But when the spring pressure is equal to 0.0866 MPa, the friction factor is not almost influenced by the rotational speed. When the rotational speed and spring pressure are less, the medium pressure has a less influence on the friction factor. When the rotational speed or spring pressure is bigger, the bigger the medium pressure, the less the friction factor.

  19. Study and Development of Face-Contact, Bellows Mechanical Seal for Liquid Hydrogen Turbopump

    OpenAIRE

    NOSAKA, Masataka; SUZUKI, Mineo; MIYAKAWA, Yukio; KAMIJO, Kenjiro; KIKUCHI, Masataka; MORI, Masahiro; 野坂, 正隆; 鈴木, 峰男; 宮川, 行雄; 上絛, 謙二郎; 菊池, 正孝; 森, 雅裕

    1981-01-01

    The development of a 10-ton thrust liquid oxygen and liquid hydrogen (LOX and LH2) rocket engine is under way at the National Space Development Agency. In advance of the development of a liquid hydrogen turbopump, the National Aerospace Laboratory carried out study and development of a face-contact, bellows mechanical seal for a liquid hydrogen turbopump in co-operation with the National Space Development Agency. The present report describes the fundamental experiments of the mechanical seal ...

  20. Process and device for in situ replacing sealing faces in large valves

    International Nuclear Information System (INIS)

    Francois, M.; Garit, J.; Mantes, G.

    1995-01-01

    A milling machine is fitted in the interior of the valve and first machines the sealing face of the opposite seat of the seat to be replaced so that this face can act as a reference for the tool and then machines out the seat ending up by machining a new recess for the replacement seat which is then inserted in position and fixed to the body of the valve by a circular welded joint. 23 figs

  1. Coupling analysis of frictional heat of fluid film and thermal deformation of mechanical seal end faces

    International Nuclear Information System (INIS)

    Zhou Jianfeng; Gu Boqin

    2007-01-01

    The heat transfer model of the rotating ring and the stationary ring of mechanical seal was built. The method to calculate the frictional heat that transferred by the rings was given. the coupling analysis of the frictional heat of fluid film and thermal deformation of end faces was carried out by using FEA and BP ANN, and the relationship among the rotational speed ω, the fluid film thickness h i on the inner diameter of sealing face and the radial separation angle β of deformed end faces was obtained. Corresponding to a given ω, h i and β can be obtained by the equilibrium condition between the closing force and the bearing force of fluid film. The relationship between the leakage rate and the closing force was analyzed, and the fundamental of controlling the leakage rate by regulating the closing force was also discussed. (authors)

  2. The Contact State Monitoring for Seal End Faces Based on Acoustic Emission Detection

    Directory of Open Access Journals (Sweden)

    Xiaohui Li

    2016-01-01

    Full Text Available Monitoring the contact state of seal end faces would help the early warning of the seal failure. In the acoustic emission (AE detection for mechanical seal, the main difficulty is to reduce the background noise and to classify the dispersed features. To solve these problems and achieve higher detection rates, a new approach based on genetic particle filter with autoregression (AR-GPF and hypersphere support vector machine (HSSVM is presented. First, AR model is used to build the dynamic state space (DSS of the AE signal, and GPF is used for signal filtering. Then, multiple features are extracted, and a classification model based on HSSVM is constructed for state recognition. In this approach, AR-GPF is an excellent time-domain method for noise reduction, and HSSVM has advantage on those dispersed features. Finally experimental data shows that the proposed method can effectively detect the contact state of the seal end faces and has higher accuracy rates than some other existing methods.

  3. Development of bonding techniques between W and Cu-alloys for plasma facing components by HIP method (3). Bonding tests with Au-foil insert

    International Nuclear Information System (INIS)

    Saito, Shigeru

    2002-07-01

    In recent years, it has been considered that W (tungsten) is one of candidate materials for armor tiles of plasma a facing components (PFC), like first wall or divertor, of fusion reactor. On the other hand, Cu-alloys, like OFHC-Cu or DS-Cu, are proposed as heat sink materials behind the plasma facing materials because of its high thermal conductivity. It is necessary to develop a reliable bonding techniques in order to fabricate PFC. JAERI has developed the hot isostatic press (HIP) bonding process to bond W with Cu-alloys. In this experiments, bonding tests with Au-foil insert were performed. We could get the best HIP bonding conditions for W and Cu-alloys with Au-foil as 1123K x 2hours x 147MPa. It was shown that the HIP temperature was 150K lower than that of without Au-foil. Furthermore, the tensile strength was similar to that of with without Au-foil. (author)

  4. Seals

    International Nuclear Information System (INIS)

    Welsher, R.A.G.

    1982-01-01

    An aperture through a biological shield is sealed by a flexible sheath having a beading at one end located on an annular member slidable in the aperture such that the beading bears in sealing engagement against the sides of the aperture. The annular member is retained by a retractable latch and can be rejected by pushing it out of the aperture using a replacement annular member with a replacement sheath thereon to butt against the annular member to be rejected. The replacement annular member may be mounted on a tubular device having an outer co-axial member for operating the latch when the replacement annular member butts against the annular member to be rejected. Applications include effecting a seal between a remote handling equipment and a wall through which the equipment extends. (author)

  5. FOIL ELEMENT FOR NUCLEAR REACTOR

    Science.gov (United States)

    Noland, R.A.; Walker, D.E.; Spinrad, B.I.

    1963-07-16

    A method of making a foil-type fuel element is described. A foil of fuel metal is perforated in; regular design and sheets of cladding metal are placed on both sides. The cladding metal sheets are then spot-welded to each other through the perforations, and the edges sealed. (AEC)

  6. Foil Artists

    Science.gov (United States)

    Szekely, George

    2010-01-01

    Foil can be shaped into almost anything--it is the all-purpose material for children's art. Foil is a unique drawing surface. It reflects, distorts and plays with light and imagery as young artists draw over it. Foil permits quick impressions of a model or object to be sketched. Foil allows artists to track their drawing moves, seeing the action…

  7. Thermal effects in two-phase flow through face seals. Ph.D. Thesis

    Science.gov (United States)

    Basu, Prithwish

    1988-01-01

    When liquid is sealed at high temperature, it flashes inside the seal due to pressure drop and/or viscous heat dissipation. Two-phase seals generally exhibit more erratic behavior than their single phase counterparts. Thermal effects, which are often neglected in single phase seal analyses, play an important role in determining seal behavior under two-phase operation. It is necessary to consider the heat generation due to viscous shear, conduction into the seal rings and convection with the leakage flow. Analytical models developed work reasonably well at the two extremes - for low leakage rates when convection is neglected and for higher leakage rates when conduction is neglected. A preliminary model, known as the Film Coefficient Model, is presented which considers conduction and convection both, and allows continuous boiling over an extended region unlike the previous low-leakage rate model which neglects convection and always forces a discrete boiling interface. Another simplified, semi-analytical model, based on the assumption of isothermal conditions along the seal interafce, has been developed for low leakage rates. The Film Coefficient Model may be used for more accurate and realistic description.

  8. Problems and criteria of quality improvement in end face mechanical seal rings through technological methods

    Science.gov (United States)

    Tarelnik, V.; Belous, A.; Antoszewski, B.; Zukov, A.

    2017-08-01

    In this paper are presented the recommendations for material’s selections of the mechanical seals rings and basic productive and operating requirements. The system of a directional selection of technology that ensures the required quality of working surfaces of the mechanical seals rings covers their entire life cycle. The mathematical frictional model is proposed as an instrument for calculating a linear and weighing abrasion of the mechanical seals rings and helps to improve selection’s criteria and the most rational method of strengthening.

  9. Foil Electron Multiplier

    Science.gov (United States)

    Funsten, Herbert O.; Baldonado, Juan R.; Dors, Eric E.; Harper, Ronnie W.; Skoug, Ruth M.

    2006-03-28

    An apparatus for electron multiplication by transmission that is designed with at least one foil having a front side for receiving incident particles and a back side for transmitting secondary electrons that are produced from the incident particles transiting through the foil. The foil thickness enables the incident particles to travel through the foil and continue on to an anode or to a next foil in series with the first foil. The foil, or foils, and anode are contained within a supporting structure that is attached within an evacuated enclosure. An electrical power supply is connected to the foil, or foils, and the anode to provide an electrical field gradient effective to accelerate negatively charged incident particles and the generated secondary electrons through the foil, or foils, to the anode for collection.

  10. High temperature autoclave vacuum seals

    Science.gov (United States)

    Hoffman, J. R.; Simpson, W. G.; Walker, H. M.

    1971-01-01

    Aluminum sheet forms effective sealing film at temperatures up to 728 K. Soft aluminum wire rings provide positive seal between foil and platen. For applications at temperatures above aluminum's service temperature, stainless steel is used as film material and copper wire as sealant.

  11. Seals and sealing handbook

    CERN Document Server

    Flitney, Robert K

    2014-01-01

    Seals and Sealing Handbook, 6th Edition provides comprehensive coverage of sealing technology, bringing together information on all aspects of this area to enable you to make the right sealing choice. This includes detailed coverage on the seals applicable to static, rotary and reciprocating applications, the best materials to use in your sealing systems, and the legislature and regulations that may impact your sealing choices. Updated in line with current trends this updated reference provides the theory necessary for you to select the most appropriate seals for the job and with its 'Failur

  12. Oscillating foil propulsion

    OpenAIRE

    Hauge, Jacob

    2013-01-01

    Unsteady foil theory is discussed and applied on several cases of an oscillating foil. The oscillating foil is meant as a propulsion system for a platform supply vessel.Four case studies of foil oscillation have been performed. A thrust coefficient of 0.1 was achieved at an efficiency of 0.75. A thrust coefficient of minimum 0.184 is necessary to overcome the calm water resistance of the foil.Issues connected to coupled vessel-foil models are discussed.

  13. Severe service sealing solutions

    International Nuclear Information System (INIS)

    Metcalfe, R.; Wensel, R.

    1994-09-01

    Successful sealing usually requires much more than initial leak-tightness. Friction and wear must also be acceptable, requiring a good understanding of tribology at the sealing interface. This paper describes various sealing solutions for severe service conditions. The CAN2A and CAN8 rotary face seals use tungsten carbide against carbon-graphite to achieve low leakage and long lifetime in nuclear main coolant pumps. The smaller CAN6 seal successfully uses tungsten carbide against silicon carbide in reactor water cleanup pump service. Where friction in CANDU fuelling machine rams must be essentially zero, a hydrostatic seal using two silicon carbide faces is the solution. In the NRU reactor moderator pumps, where pressure is much lower, eccentric seals that prevent boiling at the seal faces are giving excellent service. All these rotary face seals rely on supplementary elastomer seals between their parts. An integrated engineering approach to high performance sealing with O-rings is described. This is epitomized in critical Space Shuttle applications, but is increasingly being applied in CANDU plants. It includes gland design, selection and qualification of material, quality assurance, detection of defects and the effects of lubrication, surface finish, squeeze, stretch and volume constraints. In conclusion, for the severe service applications described, customized solutions have more than paid for themselves by higher reliability, lower maintenance requirements and reduced outage time. (author)

  14. Faces

    DEFF Research Database (Denmark)

    Mortensen, Kristine Køhler; Brotherton, Chloe

    2018-01-01

    In this chapter, we investigate how a face is not a singular, invariable object, but may take on a variety of forms, and how new media has especially created new venues for the moldings of faces. We suggest that faces should be viewed in plural in order to emphasize the many different facial disp...

  15. Rim seal arrangement having pumping feature

    Science.gov (United States)

    Lee, Ching-Pang; Myers, Caleb

    2017-04-25

    A rim seal arrangement for a gas turbine engine includes a first seal face on a rotor component, and a second seal face on a stationary annular rim centered about a rotation axis of the rotor component. The second seal face is spaced from the first seal face along an axial direction to define a seal gap. The seal gap is located between a radially outer hot gas path and a radially inner rotor cavity. The first seal face has a plurality of circumferentially spaced depressions, each having a depth in an axial direction and extending along a radial extent of the first seal face. The depressions influence flow in the seal gap such that during rotation of the rotor component, fluid in the seal gap is pumped in a radially outward direction to prevent ingestion of a gas path fluid from the hot gas path into the rotor cavity.

  16. Faces

    DEFF Research Database (Denmark)

    Mortensen, Kristine Køhler; Brotherton, Chloe

    2018-01-01

    for the face the be put into action. Based on an ethnographic study of Danish teenagers’ use of SnapChat we demonstrate how the face is used as a central medium for interaction with peers. Through the analysis of visual SnapChat messages we investigate how SnapChat requires the sender to put an ‘ugly’ face...... displays a single person make use of, and how this ‘pool of faces’ carries sociocultural meaning. While the past decades of swift technological development may seem to have diminished the role of face to face contact, the many new media has – on the contrary – established multiple new and innovative arenas...... forward. Especially the teenage girls engage in manipulating their faces into hideous expressions. However, this type of interaction is not random facial displays, but follow an ‘aesthetics of ugliness’. This aesthetics involve specific ways of looking ugly and is primarily performed by girls who have...

  17. Method and apparatus for coating thin foil with a boron coating

    Energy Technology Data Exchange (ETDEWEB)

    Lacy, Jeffrey L.

    2018-01-16

    An apparatus and a process is disclosed for applying a boron coating to a thin foil. Preferably, the process is a continuous, in-line process for applying a coating to a thin foil comprising wrapping the foil around a rotating and translating mandrel, cleaning the foil with glow discharge in an etching chamber as the mandrel with the foil moves through the chamber, sputtering the foil with boron carbide in a sputtering chamber as the mandrel moves through the sputtering chamber, and unwinding the foil off the mandrel after it has been coated. The apparatus for applying a coating to a thin foil comprises an elongated mandrel. Foil preferably passes from a reel to the mandrel by passing through a seal near the initial portion of an etching chamber. The mandrel has a translation drive system for moving the mandrel forward and a rotational drive system for rotating mandrel as it moves forward. The etching chamber utilizes glow discharge on a surface of the foil as the mandrel moves through said etching chamber. A sputtering chamber, downstream of the etching chamber, applies a thin layer comprising boron onto the surface of the foil as said mandrel moves through said sputtering chamber. Preferably, the coated foil passes from the mandrel to a second reel by passing through a seal near the terminal portion of the sputtering chamber.

  18. Influence of facial hair length, coarseness, and areal density on seal leakage of a tight-fitting half-face respirator.

    Science.gov (United States)

    Floyd, Evan L; Henry, J Blake; Johnson, David L

    2018-04-01

    OSHA regulations state that an employer shall not permit tight-fitting respirators to be worn by employees who have facial hair that comes between the skin and facepiece seal. Studies have shown that facial hair in the face seal zone can increase penetration and decrease the fit factor (FF), although the relationship between the amount and characteristics of facial hair and the increase in penetration is not well quantified. This article examines the influence of facial hair length, areal density, and coarseness on FF for one model of half-face elastomeric negative-pressure air purifying respirator. Quantitative fit tests (QNFT) were performed on 19 subjects with beards initially 0.500-in long and subsequently trimmed to 0.250, 0.125, and 0.063 in, then after a razor shave. Three fit tests were performed at each of the 5 lengths, for 285 total tests. The average diameter and areal density of cheek and chin hair were measured. Penetration was modeled as a function of hair length category, beard areal density, and hair coarseness. FF decreased with beard length, especially beyond 0.125 in. However, passing FF scores were achieved on all tests by all subjects at the smooth shave and 0.063 in conditions, and 98% of tests were passed at 0.125 in; seven subjects passed all tests at all conditions. Chin and cheek areal densities were significantly different and were only weakly correlated. Beard hair diameters were normally distributed across subjects (mean 76 µm, standard deviation 7.4 µm). Beard length and areal density, but not coarseness, were statistically significant predictors of fit using an arcsine transformed penetration model. FF decreased with increasing beard length, especially beyond 0.125 in, although FF with a "stubble" beard did not differ significantly from a smooth shave. FF also decreased with increasing areal beard hair density. Beard length and areal density negatively influence FF. However, tight-fitting half-face negative-pressure respirator

  19. Seals and sealing handbook

    CERN Document Server

    Flitney, Robert K

    2007-01-01

    Wherever machinery operates there will be seals of some kind ensuring that the machine remains lubricated, the fluid being pumped does not leak, or the gas does not enter the atmosphere. Seals are ubiquitous, in industry, the home, transport and many other places. This 5th edition of a long-established title covers all types of seal by application: static, rotary, reciprocating etc. The book bears little resemblance to its predecessors, and Robert Flitney has re-planned and re-written every aspect of the subject. No engineer, designer or manufacturer of seals can afford to be without this uniq

  20. Seals Research at AlliedSignal

    Science.gov (United States)

    Ullah, M. Rifat

    1996-01-01

    A consortium has been formed to address seal problems in the Aerospace sector of Allied Signal, Inc. The consortium is represented by makers of Propulsion Engines, Auxiliary Power Units, Gas Turbine Starters, etc. The goal is to improve Face Seal reliability, since Face Seals have become reliability drivers in many of our product lines. Several research programs are being implemented simultaneously this year. They include: Face Seal Modeling and Analysis Methodology; Oil Cooling of Seals; Seal Tracking Dynamics; Coking Formation & Prevention; and Seal Reliability Methods.

  1. Compliant seal development

    Science.gov (United States)

    Hendricks, Robert C.

    1993-10-01

    The compliant metallic seal combines the noncontact feature of the labyrinth seal, the low leakage of a mechanical seal, and the compliant nature of the brush seal. It consists of several thin metallic elements or leaves mounted within a ring which is press fit into the housing, and in form, sort of resembles a lip seal sections wiping the shaft. A second set of overlapping cover leaves are placed on top of the shaft riding leaves which reduces leakage and provides stiffness. The leaves can be straight or angle cut. The shaft riding fingers are designed with mismatched curvature to provide lift off similar to the Rayleigh lift pads in mechanical seals with leading edge clearances nearly twice those of the trailing edge as as shown by Fleming to be optimal for gas flows in convergent seal passages. Leading edge clearances range from 300 to 500 microinches. Balance pockets beneath the leaves provide fluid film feed to the 'Rayleigh lift' surface and the proper balance ratio (mechanical seal) when combined with the static pressure and film pressure. The leaves flex in the radial direction and accommodate thermomechanical behavior as well as axial motion and angular misalignment. In the static mode, there is a net closing force on the leaves. The seals were tested to 70 psi at speeds to 16,000 rpm or surface speeds to 330 fps and temperatures from ambient to 440 F. A slow cycle through the rig critical at 10,000 rpm induced a radial vibration response of 0.004 to 0.005 inch were accommodated by the seal. Preliminary performance data are encouraging demonstrating hydrodynamic liftoff and noncontacting operation at pressure and speeds typical of gas turbine engines. The leakage performance data are significantly better than commercial labyrinth and brush seals which should be expected as this design incorporates the features of the low leakage face or mechanical seal along with the flexibility of the brush configuration.

  2. Glass sealing

    Energy Technology Data Exchange (ETDEWEB)

    Brow, R.K.; Kovacic, L.; Chambers, R.S. [Sandia National Labs., Albuquerque, NM (United States)

    1996-04-01

    Hernetic glass sealing technologies developed for weapons component applications can be utilized for the design and manufacture of fuel cells. Design and processing of of a seal are optimized through an integrated approach based on glass composition research, finite element analysis, and sealing process definition. Glass sealing procedures are selected to accommodate the limits imposed by glass composition and predicted calculations.

  3. Circuit design on plastic foils

    CERN Document Server

    Raiteri, Daniele; Roermund, Arthur H M

    2015-01-01

    This book illustrates a variety of circuit designs on plastic foils and provides all the information needed to undertake successful designs in large-area electronics.  The authors demonstrate architectural, circuit, layout, and device solutions and explain the reasons and the creative process behind each. Readers will learn how to keep under control large-area technologies and achieve robust, reliable circuit designs that can face the challenges imposed by low-cost low-temperature high-throughput manufacturing.   • Discusses implications of problems associated with large-area electronics and compares them to standard silicon; • Provides the basis for understanding physics and modeling of disordered material; • Includes guidelines to quickly setup the basic CAD tools enabling efficient and reliable designs; • Illustrates practical solutions to cope with hard/soft faults, variability, mismatch, aging and bias stress at architecture, circuit, layout, and device levels.

  4. Monolithic exploding foil initiator

    Science.gov (United States)

    Welle, Eric J; Vianco, Paul T; Headley, Paul S; Jarrell, Jason A; Garrity, J. Emmett; Shelton, Keegan P; Marley, Stephen K

    2012-10-23

    A monolithic exploding foil initiator (EFI) or slapper detonator and the method for making the monolithic EFI wherein the exploding bridge and the dielectric from which the flyer will be generated are integrated directly onto the header. In some embodiments, the barrel is directly integrated directly onto the header.

  5. Navy GTE seal development activity

    Science.gov (United States)

    Grala, Carl P.

    1993-10-01

    Under the auspices of the Integrated High Performance Turbine Engine Technology Initiative, the Naval Air Warfare Center conducts advanced development programs for demonstration in the next generation of air-breathing propulsion systems. Among the target technologies are gas path and lube oil seals. Two development efforts currently being managed by NAWCAD are the High Performance Compressor Discharge Film-Riding Face Seal and the Subsonic Core High Speed Air/Oil Seal. The High Performance Compressor Discharge Film-Riding Face Seal Program aims at reducing parasitic leakage through application of a film-riding face sea concept to the compressor discharge location of a Phase 2 IHPTET engine. An order-of-magnitude leakage reduction relative to current labyrinth seal configurations is expected. Performance goals for these seals are (1) 1200 F air temperature, (2) 800 feet-per-second surface velocity, and (3) 600 SPI differential pressure. The two designs chosen for fabrication and rig test are a spiral groove and a Rayleigh step seal. Rig testing is currently underway. The Subsonic Core High Speed Air/Oil Seal Program is developing shaft-to-ground seals for next-generation propulsion systems that will minimize leakage and provide full life. Significantly higher rotor speeds and temperatures will be experienced. Technologies being exploited include, hydrodynamic lift assist features, ultra light weight designs, and improved cooling schemes. Parametric testing has been completed; a final seal design is entering the endurance test phase.

  6. Process for anodizing aluminum foil

    International Nuclear Information System (INIS)

    Ball, J.A.; Scott, J.W.

    1984-01-01

    In an integrated process for the anodization of aluminum foil for electrolytic capacitors including the formation of a hydrous oxide layer on the foil prior to anodization and stabilization of the foil in alkaline borax baths during anodization, the foil is electrochemically anodized in an aqueous solution of boric acid and 2 to 50 ppm phosphate having a pH of 4.0 to 6.0. The anodization is interrupted for stabilization by passing the foil through a bath containing the borax solution having a pH of 8.5 to 9.5 and a temperature above 80 0 C. and then reanodizing the foil. The process is useful in anodizing foil to a voltage of up to 760 V

  7. Mechanical seals

    CERN Document Server

    Mayer, E

    1977-01-01

    Mechanical Seals, Third Edition is a source of practical information on the design and use of mechanical seals. Topics range from design fundamentals and test rigs to leakage, wear, friction and power, reliability, and special designs. This text is comprised of nine chapters; the first of which gives a general overview of seals, including various types of seals and their applications. Attention then turns to the fundamentals of seal design, with emphasis on six requirements that must be considered: sealing effectiveness, length of life, reliability, power consumption, space requirements, and c

  8. Foil Gas Thrust Bearings for High-Speed Turbomachinery

    Science.gov (United States)

    Edmonds, Brian; DellaCorte, Christopher; Dykas, Brian

    2010-01-01

    A methodology has been developed for the design and construction of simple foil thrust bearings intended for parametric performance testing and low marginal costs, supporting continued development of oil-free turbomachinery. A bearing backing plate is first machined and surface-ground to produce flat and parallel faces. Partial-arc slots needed to retain the foil components are then machined into the plate by wire electrical discharge machining. Slot thicknesses achievable by a single wire pass are appropriate to accommodate the practical range of foil thicknesses, leaving a small clearance in this hinged joint to permit limited motion. The backing plate is constructed from a nickel-based superalloy (Inconel 718) to allow heat treatment of the entire assembled bearing, as well as to permit hightemperature operation. However, other dimensionally stable materials, such as precipitation-hardened stainless steel, can also be used for this component depending on application. The top and bump foil blanks are cut from stacks of annealed Inconel X-750 foil by the same EDM process. The bump foil has several azimuthal slits separating it into five individual bump strips. This configuration allows for variable bump spacing, which helps to accommodate the effects of the varying surface velocity, thermal crowning, centrifugal dishing, and misalignment. Rectangular tabs on the foil blanks fit into the backing plate slots. For this application, a rather traditional set of conventionally machined dies is selected, and bump foil blanks are pressed into the dies for forming. This arrangement produces a set of bump foil dies for foil thrust bearings that provide for relatively inexpensive fabrication of various bump configurations, and employing methods and features from the public domain.

  9. Security seal

    Science.gov (United States)

    Gobeli, Garth W.

    1985-01-01

    Security for a package or verifying seal in plastic material is provided by a print seal with unique thermally produced imprints in the plastic. If tampering is attempted, the material is irreparably damaged and thus detectable. The pattern of the imprints, similar to "fingerprints" are recorded as a positive identification for the seal, and corresponding recordings made to allow comparison. The integrity of the seal is proved by the comparison of imprint identification records made by laser beam projection.

  10. Seals for sealing a pressure vessel such as a nuclear reactor vessel or the like

    International Nuclear Information System (INIS)

    Bruns, H.J.; Huelsermann, K.H.

    1975-01-01

    A description is given of seals for sealing a pressure vessel such as a nuclear reactor vessel, steam boiler vessel, or any other vessel which is desirably sealed against pressure of the type including a housing and a housing closure that present opposed vertical sealing surfaces which define the sides of a channel. The seals of the present invention comprise at least one sealing member disposed in the channel, having at least one stop face, a base portion and two shank portions extending from the base portion to form a groove-like recess. The shank portions are provided with sealing surfaces arranged to mate with the opposed vertical pressure vessel sealing surfaces. A shank-spreading wedge element also disposed in the channel has at least one stop face and is engaged in the groove-like recess with the sealing member and wedge element stop face adjacent to each other

  11. Failure analysis and seal life prediction for contacting mechanical seals

    Science.gov (United States)

    Sun, J. J.; He, X. Y.; Wei, L.; Feng, X.

    2008-11-01

    Fault tree analysis method was applied to quantitatively investigate the causes of the leakage failure of mechanical seals. It is pointed out that the change of the surface topography is the main reasons causing the leakage of mechanical seals under the condition of constant preloads. Based on the fractal geometry theory, the relationship between the surface topography and working time were investigated by experiments, and the effects of unit load acting on seal face on leakage path in a mechanical seal were analyzed. The model of predicting seal life of mechanical seals was established on the basis of the relationship between the surface topography and working time and allowable leakage. The seal life of 108 mechanical seal operating at the system of diesel fuel storage and transportation was predicted and the problem of the condition monitoring for the long-period operation of mechanical seal was discussed by this method. The research results indicate that the method of predicting seal life of mechanical seals is feasible, and also is foundation to make scheduled maintenance time and to achieve safe-reliability and low-cost operation for industrial devices.

  12. Design, fabrication, and performance of foil journal bearing for the brayton rotating unit

    Science.gov (United States)

    Licht, L.; Branger, M.

    1973-01-01

    Foil bearings were designed and manufactured to replace pivoted-shoe journal bearings in an existing Brayton Cycle turbo-alternator-compressor. The design of this unconventional rotor support was accomplished within the constraints and space limitations imposed by the present machine, and the substitution of foil bearings was effected without changes or modification other machine components. A housing and a test rig were constructed to incorporate the new foil-bearing support into a unified assemble with an air-driven rotor and the gimbal-mounted thrust bearing, seals, and shrouds of an actual Brayton Rotating Unit. The foil bearing required no external pressure source, and stable self-acting rotation was achieved at all speeds up to 43,200 rpm. Excellent wipe-wear characteristics of the foil bearing permitted well over 1000 start-stop cycles with no deterioriation of performance in the entire speed range.

  13. Gas Foil Bearings for Space Propulsion Nuclear Electric Power Generation

    Science.gov (United States)

    Howard, Samuel A.; DellaCorte, Christopher

    2006-01-01

    The choice of power conversion technology is critical in directing the design of a space vehicle for the future NASA mission to Mars. One candidate design consists of a foil bearing supported turbo alternator driven by a helium-xenon gas mixture heated by a nuclear reactor. The system is a closed-loop, meaning there is a constant volume of process fluid that is sealed from the environment. Therefore, foil bearings are proposed due to their ability to use the process gas as a lubricant. As such, the rotor dynamics of a foil bearing supported rotor is an important factor in the eventual design. The current work describes a rotor dynamic analysis to assess the viability of such a system. A brief technology background, assumptions, analyses, and conclusions are discussed in this report. The results indicate that a foil bearing supported turbo alternator is possible, although more work will be needed to gain knowledge about foil bearing behavior in helium-xenon gas.

  14. Development of advanced seals for space propulsion turbomachinery

    Science.gov (United States)

    Hendricks, Robert C.; Liang, Anita D.; Childs, Dara W.; Proctor, Margaret P.

    1992-04-01

    Current activities in seals for space propulsion turbomachinery that NASA sponsors are surveyed. The overall objective is to provide the designer and researcher with the concepts and data to control seal dynamics and leakage. Included in the program are low-leakage seals, such as the brush seal, the 'ceramic rope' seal, low-leakage seals for liquid oxygen turbopumps, face seals for two phase flow, and swirl brakes for stability. Two major efforts are summarized: a seal dynamics in rotating machinery, and an effort in seal code development.

  15. Secondary seal effects in hydrostatic non-contact seals for reactor coolant pump shaft

    International Nuclear Information System (INIS)

    Fujita, T.; Koga, T.; Tanoue, H.; Hirabayashi, H.

    1987-01-01

    The paper presents a seal flow analysis in a hydrostatic non-contact seal for a PWR coolant pump shaft. A description is given of the non-contact seal for the reactor coolant pump. Results are presented for a distortion analysis of the seal ring, along with the seal flow characteristics and the contact pressure profiles of the secondary seals. The results of the work confirm previously reported findings that the seal ring distortion is sensitive to the o-ring location (which was placed between the ceramic seal face and the seal ring retainer). The paper concludes that the seal flow characteristics and the tracking performance depend upon the dynamic properties of the secondary seal. (U.K.)

  16. Nozzle seal

    International Nuclear Information System (INIS)

    Groff, R.D.; Vatovec, R.J.

    1978-01-01

    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

  17. Consequences of FOIL for Undergraduates

    Science.gov (United States)

    Koban, Lori; Sisneros-Thiry, Simone

    2015-01-01

    FOIL is a well-known mnemonic that is used to find the product of two binomials. We conduct a large sample (n = 252) observational study of first-year college students and show that while the FOIL procedure leads to the accurate expansion of the product of two binomials for most students who apply it, only half of these students exhibit conceptual…

  18. Mechanical seal having a double-tier mating ring

    Science.gov (United States)

    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.

  19. Ferrules seals

    Science.gov (United States)

    Smith, J.L.

    1984-07-10

    A device is provided for sealing an inner tube and an outer tube without excessively deforming the tubes. The device includes two ferrules which cooperate to form a vacuum-tight seal between the inner tube and outer tube and having mating surfaces such that overtightening is not possible. 3 figs.

  20. Ceramic Seal.

    Energy Technology Data Exchange (ETDEWEB)

    Smartt, Heidi A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Romero, Juan A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Custer, Joyce Olsen [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Hymel, Ross W. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Krementz, Dan [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Gobin, Derek [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Harpring, Larry [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Martinez-Rodriguez, Michael [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Varble, Don [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); DiMaio, Jeff [Tetramer Technologies, Pendleton, SC (United States); Hudson, Stephen [Tetramer Technologies, Pendleton, SC (United States)

    2016-11-01

    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 Administration (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.

  1. Ferrules seals

    Science.gov (United States)

    Smith, James L.

    1984-01-01

    A device is provided for sealing an inner tube and an outer tube without excessively deforming the tubes. The device includes two ferrules which cooperate to form a vacuum-tight seal between the inner tube and outer tube and having mating surfaces such that overtightening is not possible.

  2. Sealing devices

    International Nuclear Information System (INIS)

    Coulson, R.A.

    1980-01-01

    A sealing device for minimising the leakage of toxic or radioactive contaminated environments through a biological shield along an opening through which a flexible component moves that penetrates the shield. The sealing device comprises an outer tubular member which extends over a length not less than the maximum longitudinal movement of the component along the opening. An inner sealing block is located intermediate the length of the component by connectors and is positioned in the bore of the outer tubular member to slide in the bore and effect a seal over the entire longitudinal movement of the component. The cross-section of the device may be circular and the block may be of polytetrafluoroethylene or of nylon impregnated with molybdenum or may be metallic. A number of the sealing devices may be combined into an assembly for a plurality of adjacent longitudinally movable components, each adapted to sustain a tensile load, providing the various drives of a master-slave manipulator. (author)

  3. Application of radioisotope technique for investigation of pumps seals

    International Nuclear Information System (INIS)

    Antoszewski, B.; Zorawska, A.

    1988-01-01

    Radioisotope method of measuring the wear of rings of the face mechanical seals, bush in soft seals, and leakage in double mechanical seals is described. The examples are given. It is found that radioisotope technique can be used for investigation of the seals. (author)

  4. Film riding seals for rotary machines

    Science.gov (United States)

    Bidkar, Rahul Anil; Sarawate, Neelesh Nandkumar; Wolfe, Christopher Edward; Ruggiero, Eric John; Raj Mohan, Vivek Raja

    2017-03-07

    A seal assembly for a rotary machine is provided. The seal assembly includes multiple sealing device segments disposed circumferentially intermediate to a stationary housing and a rotor. Each of the segments includes a shoe plate with a forward-shoe section and an aft-shoe section having one or more labyrinth teeth therebetween facing the rotor. The sealing device includes a stator interface element having a groove or slot for allowing disposal of a spline seal for preventing segment leakages. The sealing device segment also includes multiple bellow springs or flexures connected to the shoe plate and to the stator interface element. Further, the sealing device segments include a secondary seal integrated with the stator interface element at one end and positioned about the multiple bellow springs or flexures and the shoe plate at the other end.

  5. Dynamic analysis of noncontacting hydrostatic seals

    International Nuclear Information System (INIS)

    Kokarakis, J.E.; Thomas, J.M.

    1988-01-01

    A troublesome operating history for hydrostatic seals in reactor coolant pumps motivates an investigation of the dynamics of a typical seal system. A dynamic model of the seal ring is formulated and the response of the seal to transient and steady excitation is analyzed. The model is capable of treating response of the seal ring to excitation by both pressure fluctuations at the faceplate and/or axial motion of the shaft. It also includes the effects of friction between the secondary seal and the mating insert. Damping, inherent in the fluid film between the seal faceplates, is considered by including dynamic pressure variations due to squeeze. A typical hydrostatic seal is analyzed in the numerical applications to study the interrelation between the design parameters, the stability of the system, and the potential contact between the stationery and rotating faces

  6. Seal Counts

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Database of seal counts from aerial photography. Counts by image, site, species, and date are stored in the database along with information on entanglements and...

  7. Aerodynamic seals for rotary machine

    Science.gov (United States)

    Bidkar, Rahul Anil; Cirri, Massimiliano; Thatte, Azam Mihir; Williams, John Robert

    2016-02-09

    An aerodynamic seal assembly for a rotary machine includes multiple sealing device segments disposed circumferentially intermediate to a stationary housing and a rotor. Each of the segments includes a shoe plate with a forward-shoe section and an aft-shoe section having multiple labyrinth teeth therebetween facing the rotor. The sealing device segment also includes multiple flexures connected to the shoe plate and to a top interface element, wherein the multiple flexures are configured to allow the high pressure fluid to occupy a forward cavity and the low pressure fluid to occupy an aft cavity. Further, the sealing device segments include a secondary seal attached to the top interface element at one first end and positioned about the flexures and the shoe plate at one second end.

  8. [Christmas seals].

    Science.gov (United States)

    Loytved, G

    2006-11-01

    Christmas seals, i. e., special stamps used to decorate or seal Christmas and New Year's mail, were created by the Danish post office clerk E. Holboell. The proceeds from the sale of the stickers were meant to alleviate the suffering of children sick with tuberculosis. The first Christmas seal, showing a portrait of Queen Louise of Denmark, was issued on December 10, 1904. The demand at the post office was enormous. The funds raised exceeded all expectations and made it possible to finance the construction of a sanatorium for tuberculosis children. The idea of Christmas seals spread quickly around the world and ended up being copied in 130 countries. At the beginning of the 20 (th) century, the small stamp with the red double-barred cross became a banner for the crusade against tuberculosis. For many patients, it also represented a symbol of hope for recovery even though this hope, given the cure rates of a sanatorium treatment, only became a reality for a few. Worldwide, Christmas seals were and are colourful and imaginatively designed, mostly with Christmas symbols or motives relating to the fight against tuberculosis. The funds raised through the sale of the seals initially helped to build hospitals and were later also used to screen persons at risk for tuberculosis, to improve housing conditions of patients and for other measures of support. With the decrease of tuberculosis, some organisations discontinued fundraising through Christmas seals while others widened their intended purpose and supported, for example, the prevention of and research on lung diseases. In Germany, Christmas seals are closely connected with the German Central Committee against Tuberculosis. Today the "Kuratorium Tuberkulose in der Welt" is the only organisation in this country that still raises funds by this means. The funds are mostly used to assist developing countries with a high burden of tuberculosis.

  9. System for inspection of package seal integrity

    Science.gov (United States)

    Gibson, Terry G.

    1995-10-01

    There is an increasing acceptance of reduced waste packaging methods for pharmaceutical and medical products. The high level of product integrity must be maintained, while manufacturing lines are required to increase production rates. To ensure their confidence in these packaging methods, manufacturers have turned to process validation as one method of check. In addition to that effort, automated on-line inspection has become increasingly important. Automated inspection can be used to augment manual inspection techniques that are viable at slower production rates. In this paper we explore the elements of a systematic approach that can provide 100% automatic inspection of product seals at full production rates. The various materials used to seal packages effect the system configuration. One such package sealing material is highly specular (mirror-like) laminated foil. A characteristic of this packaging method is its ability to reflect nearly all of the light from the surface. However, the heat process required to bond the seal to the package creates a coining effect where a uniform, low to medium intensity light source, transmitted at a low incident angle, can be used to identify seal defects. It is equally difficult to inspect package seals that are opaque, translucent, or transparent. Each seal material requires a specific lighting solution. When using reflective material, great care must be taken to develop and integrate the lighting method to an automated package seal inspection system.

  10. Stabilizing geometry for hydrodynamic rotary seals

    Science.gov (United States)

    Dietle, Lannie L.; Schroeder, John E.

    2010-08-10

    A hydrodynamic sealing assembly including a first component having first and second walls and a peripheral wall defining a seal groove, a second component having a rotatable surface relative to said first component, and a hydrodynamic seal comprising a seal body of generally ring-shaped configuration having a circumference. The seal body includes hydrodynamic and static sealing lips each having a cross-sectional area that substantially vary in time with each other about the circumference. In an uninstalled condition, the seal body has a length defined between first and second seal body ends which varies in time with the hydrodynamic sealing lip cross-sectional area. The first and second ends generally face the first and second walls, respectively. In the uninstalled condition, the first end is angulated relative to the first wall and the second end is angulated relative to the second wall. The seal body has a twist-limiting surface adjacent the static sealing lip. In the uninstalled condition, the twist-limiting surface is angulated relative to the peripheral wall and varies along the circumference. A seal body discontinuity and a first component discontinuity mate to prevent rotation of the seal body relative to the first component.

  11. Foil-to-foil system integration through capillary self-alignment directed by laser patterning

    OpenAIRE

    Arutinov, G Gari; Mastrangeli, M; Smits, ECP Edsger; Heck, van, G; Toonder, den, JMJ Jaap; Dietzel, AH Andreas

    2015-01-01

    This paper introduces a new integration technology for cost-effective high-precision mechanical and electrical integration of mesoscopic functional foil components onto foil substrates. The foil-to-foil assembly process is based on topological surface structuring via laser patterning that enables accurate capillarity-driven self-alignment of foil dies. The concurrent establishment of high-yield electrical interconnections is obtained through conductive adhesives. The foil surface energy contr...

  12. Post-foil interaction in foil-induced molecular dissociation

    International Nuclear Information System (INIS)

    Faibis, A.; Kanter, E.P.; Koenig, W.; Plesser, I.; Vager, Z.

    1985-01-01

    The authors have investigated the foil-induced dissociation of 175- 250- keV/amu CH + , NH + , and OH + , FH + and NeH + ions by coincident detection of the fragment atoms. The dissociation energies corresponding to in-foil and post-foil interactions were deduced from the measured relative flight times of the fragment pairs to a set of detectors downstream from the target. The authors considered final states consisting of a) a proton and a heavy-ion and, b) a hydrogen atom and a heavy-ion. Surprisingly, in both cases the energy released in the post-target interaction shows a similar linear increase with the charge state of the heavy partner

  13. Air riding seal with purge cavity

    Science.gov (United States)

    Sexton, Thomas D; Mills, Jacob A

    2017-08-15

    An air riding seal for a turbine in a gas turbine engine, where an annular piston is axial moveable within an annular piston chamber formed in a stator of the turbine and forms a seal with a surface on the rotor using pressurized air that forms a cushion in a pocket of the annular piston. A purge cavity is formed on the annular piston and is connected to a purge hole that extends through the annular piston to a lower pressure region around the annular piston or through the rotor to an opposite side. The annular piston is sealed also with inner and outer seals that can be a labyrinth seal to form an additional seal than the cushion of air in the pocket to prevent the face of the air riding seal from overheating.

  14. Numerical and experimental investigation of bump foil mechanical behaviour

    DEFF Research Database (Denmark)

    Larsen, Jon Steffen; Cerda Varela, Alejandro Javier; Santos, Ilmar

    2014-01-01

    Corrugated foils are utilized in air foil bearings to introduce compliance and damping thus accurate mathematical predictions are important. A corrugated foil behaviour is investigated experimentally as well as theoretically. The experimental investigation is performed by compressing the foil...

  15. kFOIL: Learning simple relational kernels

    OpenAIRE

    Landwehr, Niels; Passerini, Andrea; De Raedt, Luc; Frasconi, Paolo

    2006-01-01

    A novel and simple combination of inductive logic programming with kernel methods is presented. The kFOIL algorithm integrates the well-known inductive logic programming system FOIL with kernel methods. The feature space is constructed by leveraging FOIL search for a set of relevant clauses. The search is driven by the performance obtained by a support vector machine based on the resulting kernel. In this way, kFOIL implements a dynamic propositionalization approach. Both classification an...

  16. Foil-to-Foil system integration through capillary self-alignment directed by laser patterning

    NARCIS (Netherlands)

    Arutinov, G.; Mastrangeli, M.; Smits, E.C.P.; Heck, G. van; Toonder, J.M.J. den; Dietzel, A.H.

    2014-01-01

    This paper introduces a new integration technology for cost-effective high-precision mechanical and electrical integration of mesoscopic functional foil components onto foil substrates. The foil-to-foil assembly process is based on topological surface structuring via laser patterning that enables

  17. Passive Thermal Management of Foil Bearings

    Science.gov (United States)

    Bruckner, Robert J. (Inventor)

    2015-01-01

    Systems and methods for passive thermal management of foil bearing systems are disclosed herein. The flow of the hydrodynamic film across the surface of bearing compliant foils may be disrupted to provide passive cooling and to improve the performance and reliability of the foil bearing system.

  18. Actively controlled shaft seals for aerospace applications

    Science.gov (United States)

    Salant, Richard F.

    1995-07-01

    This study experimentally investigates an actively controlled mechanical seal for aerospace applications. The seal of interest is a gas seal, which is considerably more compact than previous actively controlled mechanical seals that were developed for industrial use. In a mechanical seal, the radial convergence of the seal interface has a primary effect on the film thickness. Active control of the film thickness is established by controlling the radial convergence of the seal interface with a piezoelectric actuator. An actively controlled mechanical seal was initially designed and evaluated using a mathematical model. Based on these results, a seal was fabricated and tested under laboratory conditions. The seal was tested with both helium and air, at rotational speeds up to 3770 rad/sec, and at sealed pressures as high as 1.48 x 10(exp 6) Pa. The seal was operated with both manual control and with a closed-loop control system that used either the leakage rate or face temperature as the feedback. The output of the controller was the voltage applied to the piezoelectric actuator. The seal operated successfully for both short term tests (less than one hour) and for longer term tests (four hours) with a closed-loop control system. The leakage rates were typically 5-15 slm (standard liters per minute), and the face temperatures were generally maintained below 100C. When leakage rate was used as the feedback signal, the setpoint leakage rate was typically maintained within 1 slm. However, larger deviations occurred during sudden changes in sealed pressure. When face temperature was used as the feedback signal, the setpoint face temperature was generally maintained within 3 C, with larger deviations occurring when the sealed pressure changes suddenly. the experimental results were compared to the predictions from the mathematical model. The model was successful in predicting the trends in leakage rate that occurred as the balance ratio and sealed pressure changed

  19. Rotatable seal assembly. [Patent application; rotating targets

    Science.gov (United States)

    Logan, C.M.; Garibaldi, J.L.

    1980-11-12

    An assembly is provided for rotatably supporting a rotor on a stator so that vacuum chambers in the rotor and stator remain in communication while the chambers are sealed from ambient air, which enables the use of a ball bearing or the like to support most of the weight of the rotor. The apparatus includes a seal device mounted on the rotor to rotate therewith, but shiftable in position on the rotor while being sealed to the rotor as by an O-ring. The seal device has a flat face that is biased towards a flat face on the stator, and pressurized air is pumped between the faces to prevent contact between them while spacing them a small distance apart to avoid the inflow of large amounts of air between the faces and into the vacuum chambers.

  20. Development of a new foil positioning mechanism

    International Nuclear Information System (INIS)

    Ansari, Q.N.; Bhagwat, P.V.; Gupta, A.K.; Choudhury, R.K.

    2009-01-01

    In a tandem accelerator, negative ions are accelerated to high voltage terminal where beam pass through a foil stripper/gas stripper or combination of both, ultimately positive ions accelerated. The optimum thickness of stripper foil is in the range of 3-5 μg/cm 2 for 14 MeV ion beam. A new foil changing system for Pelletron Accelerator has been developed based on micro-stepping stepper motor arrangement. Present Geneva based mechanism is driven by the AC motor using belt and pulley, which rotates by 90° for each revolution of motor shaft and brings the foil in position with beam axis. The belt carries 200 foils and due to prolonged usage and subsequent slackness of the belt, the foil position is not reproducible. Also, it is found that sometimes foil position is proper either in increase or in decrease mode. There is no provision to adjust foil position with respect to beam axis in the current mechanism. To overcome this problem a new stepper motor based system is under development which uses smooth rotation and fine positioning. Micro-controller chip used is programmed to control the rotation and select the foils in increase/decrease mode. In addition, a fine control is also provided to adjust the angular position of foil to avail optimum transmission. This paper presents the salient features of the foil positioning mechanism. (author)

  1. Upgrading primary heat transport pump seals

    International Nuclear Information System (INIS)

    Graham, T.; Metcalfe, R.; Rhodes, D.; McInnes, D.

    1995-01-01

    Changes in the operating environment at the Bruce-A Nuclear Generating Station created the need for an upgraded Primary Heat Transport Pump (PHTP) seal. In particular, the requirement for low pressure running during more frequent start-ups exposed a weakness of the CAN2 seal and reduced its reliability. The primary concern at Bruce-A was the rotation of the CAN2 No. 2 stators in their holders. The introduction of low pressure running exacerbated this problem, giving rapid wear of the stator back face, overheating, and thermocracking. In addition, the resulting increase in friction between the stator and its holder increased stationary-side hysteresis and thereby changed the seal characteristic to the point where interseal pressure oscillations became prevalent. The resultant increased hysteresis also led to hard rubbing of the seal faces during temperature transients. An upgraded seal was required for improved reliability to avoid forced outages and to reduce maintenance costs. This paper describes this upgraded 'replacement seal' and its performance history. In spite of the 'teething' problems detailed in this paper, there have been no forced outages due to the replacement seal, and in the words of a seal maintenance worker at Bruce-A, 'it allows me to go home and sleep at night instead of worrying about seal failures.' (author)

  2. Zika Vaccine Development: Flavivirus Foils

    Science.gov (United States)

    2016-09-01

    Martins, Bavari, Zika Vaccine Development 1 Zika Vaccine Development: Flavivirus Foils Martins KAO, Bavari S. The current Zika virus...contrast, work had been underway for decades on the development of an Ebola virus vaccine , laying the groundwork for a rapid response in 2014. The...broader community’s extensive experience with Dengue virus vaccine development and with the pros and cons of different vaccine platforms has led to

  3. Reactor coolant pump shaft seal behavior during station blackout

    International Nuclear Information System (INIS)

    Kittmer, C.A.; Wensel, R.G.; Rhodes, D.B.; Metcalfe, R.; Cotnam, B.M.; Gentili, H.; Mings, W.J.

    1985-04-01

    A testing program designed to provide fundamental information pertaining to the behavior of reactor coolant pump (RCP) shaft seals during a postulated nuclear power plant station blackout has been completed. One seal assembly, utilizing both hydrodynamic and hydrostatic types of seals, was modeled and tested. Extrusion tests were conducted to determine if seal materials could withstand predicted temperatures and pressures. A taper-face seal model was tested for seal stability under conditions when leaking water flashes to steam across the seal face. Test information was then used as the basis for a station blackout analysis. Test results indicate a potential problem with an elastomer material used for O-rings by a pump vendor; that vendor is considering a change in material specification. Test results also indicate a need for further research on the generic issue of RCP seal integrity and its possible consideration for designation as an unresolved safety issue

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

    Science.gov (United States)

    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

  5. Method and system to facilitate sealing in gas turbines

    Science.gov (United States)

    Morgan, Victor John; Foster, Gregory Thomas; Sarawate, Neelesh Nandkumar

    2017-09-12

    A method and system for sealing between components within a gas turbine is provided. A first recess defined in a first component receives a seal member. A second recess defined in a second component adjacent the first component also receives the seal member. The first and second recesses are located proximate a hot gas path defined through the gas turbine, and define circumferential paths about the turbine axis. The seal member includes a sealing face that extends in a direction substantially parallel to the turbine axis. The seal member also includes a plurality of seal layers, wherein at least one of the seal layers includes at least one stress relief region for facilitating flexing of the first seal member.

  6. Note: Radial-thrust combo metal mesh foil bearing for microturbomachinery.

    Science.gov (United States)

    Park, Cheol Hoon; Choi, Sang Kyu; Hong, Doo Euy; Yoon, Tae Gwang; Lee, Sung Hwi

    2013-10-01

    This Note proposes a novel radial-thrust combo metal mesh foil bearing (MMFB). Although MMFBs have advantages such as higher stiffness and damping over conventional air foil bearings, studies related to MMFBs have been limited to radial MMFBs. The novel combo MMFB is composed of a radial top foil, thrust top foils, and a ring-shaped metal mesh damper--fabricated by compressing a copper wire mesh--with metal mesh thrust pads for the thrust bearing at both side faces. In this study, the combo MMFB was fabricated in half-split type to support the rotor for a micro gas turbine generator. The manufacture and assembly process for the half-split-type combo MMFB is presented. In addition, to verify the proposed combo MMFB, motoring test results up to 250,000 rpm and axial displacements as a function of rotational speed are presented.

  7. Technical Development Path for Gas Foil Bearings

    Science.gov (United States)

    Dellacorte, Christopher

    2016-01-01

    Foil gas bearings are in widespread commercial use in air cycle machines, turbocompressors and microturbine generators and are emerging in more challenging applications such as turbochargers, auxiliary power units and propulsion gas turbines. Though not well known, foil bearing technology is well over fifty years old. Recent technological developments indicate that their full potential has yet to be realized. This paper investigates the key technological developments that have characterized foil bearing advances. It is expected that a better understanding of foil gas bearing development path will aid in future development and progress towards more advanced applications.

  8. Performance Analysis of Gas Foil Bearing with Different Foil Pivot Configuration

    OpenAIRE

    Milind Babasaheb Patil; Karuna Kalita; Sashindra K. Kakoty

    2013-01-01

    A numerical model is developed in order to find out the performance characteristics of gas foil bearings. The static performance analysis of gas foil bearings has been carried out using an elastic foundation model of the foil. The steady state results have been compared with the experimental and theoretical results available in the literature. The characteristics of the bearing have been investigated with change in foil pivot position. It has been shown that the load carrying capacity is diff...

  9. Radiation lifetimes and failure mechanisms of carbon stripper foils

    International Nuclear Information System (INIS)

    Auble, R.L.

    1981-01-01

    Measurements of lifetimes of thin carbon foils under heavy-ion irradiation are compiled and recent advances in stripper foil technology are reviewed. The impact of recent foil lifetime improvements, many by more than an order of magnitude, on heavy-ion electrostatic accelerators is discussed. Foil inhomogeneities, particularly those caused by sputtering are suggested to be a prime factor in usable foil lifetimes

  10. A New Analysis Tool Assessment for Rotordynamic Modeling of Gas Foil Bearings

    Science.gov (United States)

    Howard, Samuel A.; SanAndres, Luis

    2010-01-01

    Gas foil bearings offer several advantages over traditional bearing types that make them attractive for use in high-speed turbomachinery. They can operate at very high temperatures, require no lubrication supply (oil pumps, seals, etc.), exhibit very long life with no maintenance, and once operating airborne, have very low power loss. The use of gas foil bearings in high-speed turbomachinery has been accelerating in recent years, although the pace has been slow. One of the contributing factors to the slow growth has been a lack of analysis tools, benchmarked to measurements, to predict gas foil bearing behavior in rotating machinery. To address this shortcoming, NASA Glenn Research Center (GRC) has supported the development of analytical tools to predict gas foil bearing performance. One of the codes has the capability to predict rotordynamic coefficients, power loss, film thickness, structural deformation, and more. The current paper presents an assessment of the predictive capability of the code, named XLGFBTH (Texas A&M University). A test rig at GRC is used as a simulated case study to compare rotordynamic analysis using output from the code to actual rotor response as measured in the test rig. The test rig rotor is supported on two gas foil journal bearings manufactured at GRC, with all pertinent geometry disclosed. The resulting comparison shows that the rotordynamic coefficients calculated using XLGFBTH represent the dynamics of the system reasonably well, especially as they pertain to predicting critical speeds.

  11. Mechanical seal with textured sidewall

    Energy Technology Data Exchange (ETDEWEB)

    Khonsari, Michael M.; Xiao, Nian

    2017-02-14

    The present invention discloses a mating ring, a primary ring, and associated mechanical seal having superior heat transfer and wear characteristics. According to an exemplary embodiment of the present invention, one or more dimples are formed onto the cylindrical outer surface of a mating ring sidewall and/or a primary ring sidewall. A stationary mating ring for a mechanical seal assembly is disclosed. Such a mating ring comprises an annular body having a central axis and a sealing face, wherein a plurality of dimples are formed into the outer circumferential surface of the annular body such that the exposed circumferential surface area of the annular body is increased. The texture added to the sidewall of the mating ring yields superior heat transfer and wear characteristics.

  12. Advanced Seal Development for Large Industrial Gas Turbines

    Science.gov (United States)

    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.

  13. A metal-lustrous porphyrin foil.

    Science.gov (United States)

    Morisue, Mitsuhiko; Hoshino, Yuki; Shimizu, Masaki; Tomita, Shogo; Sasaki, Sono; Sakurai, Shinichi; Hikima, Takaaki; Kawamura, Ayaka; Kohri, Michinari; Matsui, Jun; Yamao, Takeshi

    2017-09-26

    A metal-lustrous self-standing film, named "porphyrin foil", was formed from a glass-forming polymeric porphyrin. The amorphous glass nature of the porphyrin foil played a key role in spontaneously producing a smooth surface. Its sharp contrast in intense absorption and specular reflection of light at each wavelength provided a brilliant metallic lustre.

  14. Dress Images on Gold-foil Figures

    DEFF Research Database (Denmark)

    Mannering, Ulla; Andersson Strand, Eva Birgitta

    2009-01-01

    From the Late Iron Age settlement Sorte Muld on Bornholm both gold foil figures with depictions of costumes and textile tools can tell about textile production.......From the Late Iron Age settlement Sorte Muld on Bornholm both gold foil figures with depictions of costumes and textile tools can tell about textile production....

  15. Mechanical Seal Assembly

    Energy Technology Data Exchange (ETDEWEB)

    Kotlyar, Oleg M.

    1999-06-18

    An improved mechanical seal assembly is provided for sealing rotating shafts with respect to their shaft housings, wherein the rotating shafts are subject to substantial axial vibrations. The mechanical seal assembly generally includes a rotating sealing ring fixed to the shaft, a non-rotating sealing ring adjacent to and in close contact with the rotating sealing ring for forming an annular seal about the shaft, and a mechanical diode element that applies a biasing force to the non-rotating sealing ring by means of hemispherical joint. The alignment of the mechanical diode with respect to the sealing rings is maintained by a series of linear bearings positioned axially along a desired length of the mechanical diode. Alternative embodiments include mechanical or hydraulic amplification components for amplifying axial displacement of the non-rotating sealing ring and transferring it to the mechanical diode.

  16. Mechanical seal assembly

    Science.gov (United States)

    Kotlyar, Oleg M.

    2001-01-01

    An improved mechanical seal assembly is provided for sealing rotating shafts with respect to their shaft housings, wherein the rotating shafts are subject to substantial axial vibrations. The mechanical seal assembly generally includes a rotating sealing ring fixed to the shaft, a non-rotating sealing ring adjacent to and in close contact with the rotating sealing ring for forming an annular seal about the shaft, and a mechanical diode element that applies a biasing force to the non-rotating sealing ring by means of hemispherical joint. The alignment of the mechanical diode with respect to the sealing rings is maintained by a series of linear bearings positioned axially along a desired length of the mechanical diode. Alternative embodiments include mechanical or hydraulic amplification components for amplifying axial displacement of the non-rotating sealing ring and transferring it to the mechanical diode.

  17. Seal design alternatives study

    International Nuclear Information System (INIS)

    Van Sambeek, L.L.; Luo, D.D.; Lin, M.S.; Ostrowski, W.; Oyenuga, D.

    1993-06-01

    This report presents the results from a study of various sealing alternatives for the WIPP sealing system. Overall, the sealing system has the purpose of reducing to the extent possible the potential for fluids (either gas or liquid) from entering or leaving the repository. The sealing system is divided into three subsystems: drift and panel seals within the repository horizon, shaft seals in each of the four shafts, and borehole seals. Alternatives to the baseline configuration for the WIPP seal system design included evaluating different geometries and schedules for seal component installations and the use of different materials for seal components. Order-of-magnitude costs for the various alternatives were prepared as part of the study. Firm recommendations are not presented, but the advantages and disadvantages of the alternatives are discussed. Technical information deficiencies are identified and studies are outlined which can provide required information

  18. Measurements of activation products associated with Havar foils from a GE PETtrace medical cyclotron using high resolution gamma spectroscopy.

    Science.gov (United States)

    Manickam, Vivek; Brey, Richard R; Jenkins, Peter A; Christian, Paul E

    2009-02-01

    Havar foils are specially engineered for beam-line windows used in the General Electric (GE) PETtrace medical cyclotron that can withstand the high pressure differentials and also temperatures developed near the target with proton bombardment. These foils effectively separate components along the beam line of the cyclotron. Various activation products are produced in the foils from the primary proton beam and other secondary radiations. An accurate estimate of the activation products is necessary for the disposal of these foils. The foils were assayed using two High Purity Germanium (HPGe) detectors calibrated over a wide energy range. These were positioned at different distances (0.10 m, 0.24 m, and 1.74 m) away from the detector faces to accommodate their high activities. A summary of the anticipated relative abundance of each activation product and a scatter plot of the average exposure rate per unit charge incident on the foil vs. time post-activation are provided. A detailed spectral analysis of the foils in the energy ranges between 12 keV to 300 keV and 12 keV through 2,500 keV revealed the residual activation products 56Co, 57Co, 58Co, 54Mn, and 183Re at 264 d post-irradiation. Spectral examinations of the different foils removed between 2003 and 2005 show the same activation products regardless of the irradiation time or foil position in the target assembly. The information presented in this paper can be used along with the integrated charge incident on the foils in estimating the activity of Havar foils for the purpose of disposal.

  19. Mechanical seal program

    International Nuclear Information System (INIS)

    Lowery, G.B.

    1983-01-01

    The experimental plans and timing for completion of the mechanical seal program for both the slurry and transfer pumps are given. The slurry pump seal program will be completed by April 1984 with turnover of two seals in pumps to SRP Tank 15H. Transfer pump seal design will be released for plant use by May 1984. Also included are various other pump and seal related tests

  20. Shape memory alloy seals for geothermal applications. Final report. Report ESG-82-14

    Energy Technology Data Exchange (ETDEWEB)

    Friske, Warren H.; Schwartzbart, Harry

    1982-07-30

    A novel temperature-actuated seal for geothermal applications is under development. This program uses the shape memory property of nickel-titanium (Nitinol) alloys to achieve an improved seal in geothermal downhole pumps. Nitinol flange face seals and pump shaft seals have been designed, fabricated, and tested. It has been demonstrated that the shape memory effect of Nitinol alloys can be utilized to activate and maintain a leaktight seal in geothermal environments.

  1. Nuclear reactor sealing system

    International Nuclear Information System (INIS)

    McEdwards, J.A.

    1983-01-01

    A liquid metal-cooled nuclear reactor sealing system is disclosed. The nuclear reactor includes a vessel sealed at its upper end by a closure head. The closure head comprises at least two components, one of which is rotatable; and the two components define an annulus therebetween. The sealing system includes at least a first and second inflatable seal disposed in series in an upper portion of the annulus. The system further includes a dip seal extending into a body of insulation located adjacent a bottom portion of the closure head. The dip seal comprises a trough formed by a lower portion of one of the components, and a seal blade pendently supported from the other component and extending downwardly into the trough. A body of liquid metal is contained in the trough which submerges a portion of the seal blade. The seal blade is provided with at least one aperture located above the body of liquid metal for providing fluid communication between the annulus intermediate the dip seal and the inflatable seals, and a body of cover gas located inside the vessel. There also is provided means for introducing a purge gas into the annulus intermediate the inflatable seals and the seal blade. The purge gas is introduced in an amount sufficient to substantially reduce diffusion of radioactive cover gas or sodium vapor up to the inflatable seals. The purge gas mixes with the cover gas in the reactor vessel where it can be withdrawn from the vessel for treatment and recycle to the vessel

  2. Miniature magnetic fluid seal working in liquid environments

    Energy Technology Data Exchange (ETDEWEB)

    Mitamura, Yoshinori, E-mail: ymitamura@par.odn.ne.jp [Graduate School of Information Science and Technology, Hokkaido University, Sapporo 060-0814 (Japan); Durst, Christopher A., E-mail: chris@procyrion.com [Procyrion, Inc., Houston, TX 77027 (United States)

    2017-06-01

    This study was carried out to develop a miniature magnetic fluid (MF) seal working in a liquid environment. The miniature MF seal is intended for use in a catheter blood pump. The requirements for the MF seal included a size of less than Ø4×4.5 mm, shaft diameter of 1 mm, sealing pressure of 200 mmHg, shaft speed of up to 40000 rpm, and life of one month. The miniature MF seal was composed of an NdFeB magnet (Ø4×Ø2×1) sandwiched between two pole pieces (Ø4×Ø1.1×0.5). A shield (Ø4×Ø1.2×1.5) was placed on the pole piece facing the liquid to minimize the influence of pump flow on the MF. The seal was installed on a Ø1 shaft. A seal was formed by injecting MF (Ms: 47.8 kA/m and η: 0.5 Pa·sec) into the gap between the pole pieces and the shaft. Total volume of the MF seal was 44 μL. A sealing pressure of 370 mmHg was obtained at motor speeds of 0-40,000 rpm. The seal remained perfect for 10 days in saline under the condition of a pump flow of 1.5 L/min (The test was terminated in accordance with plans). The seal remained intact after ethylene oxide sterilization during which the seal was exposed to high pressures. In conclusion, the newly developed MF seal will be useful for a catheter pump. - Highlights: • A miniature magnetic fluid seal working in a liquid environment was developed. • The seal can be installed on Ø1 mm shaft and can seal against 370 mmHg at 40000 rpm. • The magnetic fluid seal will be useful for a catheter blood pump.

  3. Hyaluronan-lecithin foils and their properties

    Energy Technology Data Exchange (ETDEWEB)

    BiaIopiotrowicz, Tomasz [Department of Interfacial Phenomena, Faculty of Chemistry, Maria Curie-SkIodowska University, Maria Curie-SkIodowska Square 3, 20-031 Lublin (Poland); Janczuk, BronisIaw [Department of Interfacial Phenomena, Faculty of Chemistry, Maria Curie-SkIodowska University, Maria Curie-SkIodowska Square 3, 20-031 Lublin (Poland); Fiedorowicz, Maciej [Department of Chemistry, Agricultural University of Krakow, Mickiewicz Ave., 21, 31 120 Cracow (Poland); Khachatryan, Gohar [Department of Chemistry, Agricultural University of Krakow, Mickiewicz Ave., 21, 31 120 Cracow (Poland); Tomasik, Piotr [Department of Chemistry, Agricultural University of Krakow, Mickiewicz Ave., 21, 31 120 Cracow (Poland)]. E-mail: rrtomasi@cyf-kr.edu.pl; Bakos, Dusan [Faculty of Chemical and Food Technology, Slovak Technical University, Radlinskeho 9, 812 37 Bratislava (Slovakia)

    2006-01-10

    Thin, elastic foils of good resistance to the air exposure, patented as wound healing aids, were prepared by evaporation of a blend of lecithin (L) and sodium hyaluronan (H) taken under varying proportions. The contact angle for water, glycerol, formamide, ethylene glycol and diiodomethane, was determined for these foils. The contact angle was correlated against the H:L foil composition. For all liquids but formamide the highest contact angle was noted for the H:L = 2:1 (g g{sup -1}) ratio. The contact angles provided estimation of the work of adhesion. At the same L:H ratio the work of adhesion was the lowest. It was suggested that lecithin cross-linked hyaluronan. Since the work of adhesion of the studied liquids was similar to that of diiodomethane, it could be concluded that almost all functional groups on the foil surface were completely blocked. Perhaps, at H:L = 2:1 (g g{sup -1}) a stoichiometric complex of hyaluronic acid with lecithin was formed, and polar functional groups from both reagents were involved. Foils seem to be electrostatic complexes of H with L. Foils with the H:L equal to 2:1 exhibited specific properties confirmed by the IR reflectance spectra of the foils. The thermogravimetry (TG/DTG) also revealed unique thermal behaviour confirming other specific properties of the foil of this composition. For the same ratio a thorough inspection of the scanning electron micrographs (SEM) revealed few irregularly distributed perforations of 1-2 {mu}m in diameter seen as black points, which can be recognized as pores. Properties of the foils determined in the contact angle measurements are nicely backed by the results from thermogravimetric and scanning electron microscopic studies.

  4. Analysis of Mechanical Properties for GEM Foil

    CERN Document Server

    Chin, Yuk Ming

    2016-01-01

    In view of new assembly technique of the GEM detector; in which three foils stack is stretched to get the uniform gaps among the foils. We studied the mechanical properties of the foil material. We conditioned the samples in different environments to make them extra dry and wet. As holes are the major source of the charge amplification their deformation can effect the detector performance. Therefore in our studies we also studied at which level of the stress the holes deformation is seen. These tensile and holes deformation studies can help to optimize the stress during detector assembly.

  5. Bonded Invar Clip Removal Using Foil Heaters

    Science.gov (United States)

    Pontius, James T.; Tuttle, James G.

    2009-01-01

    A new process uses local heating and temperature monitoring to soften the adhesive under Invar clips enough that they can be removed without damaging the composite underneath or other nearby bonds. Two 1x1 in. (approx.2.5x2.5 cm), 10-W/sq in. (approx.1.6-W/sq cm), 80-ohm resistive foil Kapton foil heaters, with pressure-sensitive acrylic adhesive backing, are wired in parallel to a 50-V, 1-A limited power supply. At 1 A, 40 W are applied to the heater pair. The temperature is monitored in the clip radius and inside the tube, using a dual thermocouple readout. Several layers of aluminum foil are used to speed the heat up, allowing clips to be removed in less than five minutes. The very local heating via the foil heaters allows good access for clip removal and protects all underlying and adjacent materials.

  6. Radioactivity analysis in niobium activation foils

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, G.E.

    1995-06-01

    The motivation for this study was to measure and analyze the activity of six (6) niobium (Nb) foils (the x-rays from an internal transition in Nb-93m) and apply this information with previously obtained activation foil data. The niobium data was used to determine the epithermal to MeV range for the neutron spectrum and fluence. The foil activation data was re-evaluated in a spectrum analysis code (STAY`SL) to provide new estimates of the exposure at the Los Alamos Spallation Radiation Effect Facility (LASREF). The activity of the niobium foils was measured and analyzed at the University of Missouri-Columbia (UMC) under the direction of Professor William Miller. The spectrum analysis was performed at the University of Missouri-Rolla (UMR) by Professor Gary Mueller.

  7. Magnetically Actuated Seal Project

    Data.gov (United States)

    National Aeronautics and Space Administration — FTT proposes development of a magnetically actuated dynamic seal. Dynamic seals are used throughout the turbopump in high-performance, pump-fed, liquid rocket...

  8. Seal coat research project

    Science.gov (United States)

    1999-12-01

    This study evaluates the use of seal coating as a method to protect bituminous pavements from oxidation, water infiltration, and raveling. The Minnesota Department of Transportation (Mn/DOT) applied seal coating to a roadway segment of Trunk Highway ...

  9. Magnetically Actuated Seal

    Science.gov (United States)

    Pinera, Alex

    2013-01-01

    This invention is a magnetically actuated seal in which either a single electromagnet, or multiple electromagnets, are used to control the seal's position. This system can either be an open/ close type of system or an actively controlled system.

  10. Reactor vessel sealing plug

    International Nuclear Information System (INIS)

    Dooley, R.A.

    1986-01-01

    This invention relates to an apparatus and method for sealing the cold leg nozzles of a nuclear reactor pressure vessel from a remote location during maintenance and inspection of associated steam generators and pumps while the pressure vessel and refueling canal are filled with water. The apparatus includes a sealing plug for mechanically sealing the cold leg nozzle from the inside of a reactor pressure vessel. The sealing plugs include a primary and a secondary O-ring. An installation tool is suspended within the reactor vessel and carries the sealing plug. The tool telescopes to insert the sealing plug within the cold leg nozzle, and to subsequently remove the plug. Hydraulic means are used to activate the sealing plug, and support means serve to suspend the installation tool within the reactor vessel during installation and removal of the sealing plug

  11. Method of making hermetic seals for hermetic terminal assemblies

    Science.gov (United States)

    Hsu, John S.; Marlino, Laura D.; Ayers, Curtis W.

    2010-04-13

    This invention teaches methods of making a hermetic terminal assembly comprising the steps of: inserting temporary stops, shims and jigs on the bottom face of a terminal assembly thereby blocking assembly core open passageways; mounting the terminal assembly inside a vacuum chamber using a temporary assembly perimeter seal and flange or threaded assembly interfaces; mixing a seal admixture and hardener in a mixer conveyor to form a polymer seal material; conveying the polymer seal material into a polymer reservoir; feeding the polymer seal material from the reservoir through a polymer outlet valve and at least one polymer outlet tube into the terminal assembly core thereby filling interstitial spaces in the core adjacent to service conduits, temporary stop, and the terminal assembly casing; drying the polymer seal material at room temperature thereby hermetically sealing the core of the terminal assembly; removing the terminal assembly from the vacuum chamber, and; removing the temporary stops, shims.

  12. Transient and steady state behaviour of elasto–aerodynamic air foil bearings, considering bump foil compliance and top foil inertia and flexibility: A numerical investigation

    DEFF Research Database (Denmark)

    Nielsen, Bo Bjerregaard; Santos, Ilmar F.

    2017-01-01

    This work gives a theoretical contribution to the problem of modelling air foil bearings considering large sagging effects in the calculation of the non-linear transient and steady state response of a rigid rotor. This paper consists of two parts: the development of a miltiphysics model of the air...... foils and one air foil bearing with a fully supported top foil. The steady state responses of a journal supported by these air foil bearings are investigated for varied rotational speeds and journal unbalances as well as the top foil sagging in the unsupported area. The study reveals that sub...

  13. Hermetically Sealed Compressor

    Science.gov (United States)

    Holtzapple, Mark T.

    1994-01-01

    Proposed hermetically sealed pump compresses fluid to pressure up to 4,000 atm (400 MPa). Pump employs linear electric motor instead of rotary motor to avoid need for leakage-prone rotary seals. In addition, linear-motor-powered pump would not require packings to seal its piston. Concept thus eliminates major cause of friction and wear. Pump is double-ended diaphragm-type compressor. All moving parts sealed within compressor housing.

  14. Cask systems development program seal technology

    International Nuclear Information System (INIS)

    Madsen, M.M.; Humphreys, D.L.; Edwards, K.R.

    1991-01-01

    General design or test performance requirements for radioactive materials (RAM) packages are specified in Title 10 of the US Code of Federal Regulations Part 71 (10 CFR 71). Seals that provide the containment system interface between the packaging body and the closure must function in both high- and low-temperature environments under dynamic and static conditions. Experiments were performed to characterize the performance of several seal materials at low temperatures. Helium leak tests on face seals were used to compare the materials. Materials tested include butyl, neoprene, ethylene propylene, fluorosilicone, silicone, Eypel, Kalrez, Teflon, fluorocarbon, and Teflon/silicone composites. Results show that the seal materials tested, with the exception of silicone S613-60, are not leak tight (1 x 10 -7 std cm 3 /s) at manufacturer low-temperature ratings

  15. High pressure shaft seal

    International Nuclear Information System (INIS)

    Martinson, A.R.; Rogers, V.D.

    1980-01-01

    In relation to reactor primary coolant pumps, mechanical seal assembly for a pump shaft is disclosed which features a rotating seal ring mounting system which utilizes a rigid support ring loaded through narrow annular projections in combination with centering non-sealing O-rings which effectively isolate the rotating seal ring from temperature and pressure transients while securely positioning the ring to adjacent parts. A stationary seal ring mounting configuration allows the stationary seal ring freedom of motion to follow shaft axial movement up to 3/4 of an inch and shaft tilt about the pump axis without any change in the hydraulic or pressure loading on the stationary seal ring or its carrier. (author)

  16. Capillary self-alignment of mesoscopic foil components for sensor-systems-in-foil

    NARCIS (Netherlands)

    Arutinov, G.; Smits, E.C.P.; Mastrangeli, M.; Heck, G. van; Brand, J. van den; Schoo, H.F.M.; Dietzel, A.H.

    2012-01-01

    This paper reports on the effective use of capillary self-alignment for low-cost and time-efficient assembly of heterogeneous foil components into a smart electronic identification label. Particularly, we demonstrate the accurate (better than 50m) alignment of cm-sized functional foil dies. We

  17. Foil-to-foil lamination and electrical interconnection of printed components on flexible substrates

    NARCIS (Netherlands)

    Vásquez Quintero, A.; Remoortere, B. van; Smits, E.C.P.; Brand, J. van den; Briand, D.; Schoo, H.F.M.; Rooij, N.F. de

    2013-01-01

    This paper describes and compares two integration methods to structurally laminate and interconnect foil-based components with flexible polymeric substrates. The first method uses isotropic conductive adhesives (ICA) confined in laser-ablated through foil vias (TFV), while the second one uses an

  18. Balanced (C_7, C_8)-Foil Designs and Related Designs

    OpenAIRE

    USHIO, Kazuhiko

    2011-01-01

    [Abstract] In graph theory, the decomposition problem of graphs is a very important topic. Various type of decompositions of many graphs can be seen in the literature of graph theory. This paper gives balanced (C_7, C_8)-foil designs, balanced C_15-foil designs, balanced (C_〈14〉, C_〈16〉)-foil designs, balanced C_〈30〉-foil designs, balanced C_45-foil designs, balanced C_〈60〉-foil designs, balanced C_〈75〉-foil designs, balanced C_〈90〉-foil designs, balanced C_〈105〉-foil designs, balanced C_〈120...

  19. [The taphonomic aspects of cadaverous changes in corpses, buried in the plastic foils].

    Science.gov (United States)

    Stuller, F; Straka, L; Macko, V; Krivos, D; Krajcovic, J; Novomeský, F

    2008-10-01

    The forensic expertise of the 6 human bodies, being murdered in organised crime activities, had been realised by the authors. All the cadavers were packed in plastic bags or plastic foils, then buried to the illegal graves, being prepared in advance. The detail overlook and autopsy of the bodies had disclosed, that due of almost airtight sealing of the cadavers in plastic materials, the postmortal cadaverous changes went on much slower and were manifested under a different picture, as seen in the human cadavers being buried in the standard wooden coffins. The authors point out the peculiarities of such a postmortal changes, with particular focusing on the estimation of postmortal period.

  20. Additional security features for optically variable foils

    Science.gov (United States)

    Marshall, Allan C.; Russo, Frank

    1998-04-01

    For thousands of years, man has exploited the attraction and radiance of pure gold to adorn articles of great significance. Today, designers decorate packaging with metallic gold foils to maintain the prestige of luxury items such as perfumes, chocolates, wine and whisky, and to add visible appeal and value to wide range of products. However, today's products do not call for the hand beaten gold leaf of the Ancient Egyptians, instead a rapid production technology exists which makes use of accurately coated thin polymer films and vacuum deposited metallic layers. Stamping Foils Technology is highly versatile since several different layers may be combined into one product, each providing a different function. Not only can a foil bring visual appeal to an article, it can provide physical and chemical resistance properties and also protect an article from human forms of interference, such as counterfeiting, copying or tampering. Stamping foils have proved to be a highly effective vehicle for applying optical devices to items requiring this type of protection. Credit cards, bank notes, personal identification documents and more recently high value packaged items such as software and perfumes are protected by optically variable devices applied using stamping foil technology.

  1. Lifetime measurements on carbon stripper foils

    International Nuclear Information System (INIS)

    Auble, R.L.; Galbraith, D.M.

    1981-01-01

    One of the most exciting recent developments in accelerator technology is the new breed of electrostatic accelerators. These machines have terminal potentials of 25 million volts and higher and are being built to accelerate intense beams of heavy ions. One such accelerator is now nearing completion at ORNL. A crucial component in these--as in any electrostatic accelerator--is a tiny bit of carbon in the form of a very thin foil. These foils, called stripper foils, are used to strip electrons from atoms so that they will be accelerated to high energy by the electrostatic potential. While carbon foils are not the only method of stripping electrons, they have a number of advantages over the alternative gas strippers. In particular, they produce higher charge states which are essential for providing the energetic ions required for heavy ion physics experiments. Because of the importance of stripper foils to the most efficient operation of the new ORNL accelerator, we are quite interested in their properties and in improving their performance

  2. Cryostat with Foil and MLI

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Peter K.F.; Gung, Chen-yu

    2005-10-06

    Induction cores are used to accelerate heavy ion beam array, which are built around the outer diameter of the cryostat housing the superconducting quadruple array. Compact cryostat is highly desirable to reduce the cost of the induction cores. Recent experiences in fabrication of a cryostat for single beam transport revealed that it is possible to reduce the spacing in the cryostat vacuum jacket by using low-emissivity thermal insulation material instead of conventional MLI. However, it is labor-intensive to install the new type of insulation as compared with using MLI. It is promising to build a cost-effective compact cryostat for quadruple magnet array for heavy ion beam array transport by using low-emissivity material combined with conventional MLI as radiation insulation. A matrix of insulation designs and tests will be performed as the feasibility study and for the selection of the optimal thermal insulation as the Phase I work. The selected mixed insulation will be used to build prototype compact cryostats in the Phase II project, which are aiming for housing quadruple doublet array. In this STTR phase I study, a small cryostat has been designed and built to perform calorimetric characterization of the heat load in a liquid helium vessel insulated with a vacuum layer with a nominal clearance of 3.5 mm. The vacuum clearance resembled that used in the warm-bore beam tube region in a prototype cryostat previously built for the heavy ion beam transport experiment. The vacuum clearance was geometrically restricted with a heater shell with the temperature controlled at near 300 K. Various combinations of radiation and thermal shields were installed in the tight vacuum clearance for heat load measurements. The measured heat loads are reported and compared with previous test result using a compact vacuum layer. Further developments of the thermal insulations used in the present study are discussed. The compact cryostat with foil and MLI insulation may be used in the

  3. Flexible ring seal

    International Nuclear Information System (INIS)

    Abbes, Claude; Gournier, Andre; Rouaud, Christian; Villepoix, Raymond de.

    1976-01-01

    The invention concerns a flexible metal ring seal, able to ensure a perfect seal between two bearings due to the crushing and elastic deformation properties akin to similar properties in elastomers. Various designs of seal of this kind are already known, particularly a seal made of a core formed by a helical wire spring with close-wound turns and with high axial compression ratio, closed on itself and having the shape of an annulus. This wire ring is surrounded by at least one envelope having at rest the shape of a toroidal surface of which the generating circle does not close on itself. In a particular design mode, the seal in question can include, around the internal spring, two envelopes of which one in contact with the spring is composed of a low ductility elastic metal, such as mild steel or stainless steel and the other is, on the contrary, made of a malleable metal, such as copper or nickel. The first envelope evenly distributes the partial crushing of the spring, when the seal is tightened, on the second envelope which closely fits the two surfaces between which the seal operates. The stress-crushing curve characteristic of the seal comprises two separate parts, the first with a relatively sharp slope corresponds to the start of the seal compression phase, enabling at least some of these curves to reach the requisite seal threshold very quickly, then, beyond this, a second part, practically flat, where the stress is appreciably constant for a wide operating bracket [fr

  4. Optofluidic dye laser in a foil

    DEFF Research Database (Denmark)

    Vannahme, Christoph; Christiansen, Mads Brøkner; Mappes, Timo

    2010-01-01

    First order distributed feedback optofluidic dye lasers embedded in a 350 mu m thick TOPAS (R) foil are demonstrated. They are designed in order to give high output pulse energies. Microfluidic channels and first order distributed feedback gratings are fabricated in parallel by thermal nanoimprint...... into a 100 mu m foil. The channels are closed by thermal bonding with a 250 mu m thick foil and filled with 5.10(-3) mol/l Pyrromethene 597 in benzyl alcohol. The fluid forms a liquid core single mode slab waveguide of 1.6 mu m height on a nanostructured grating area of 0.5 x 0.5 mm(2). This results...

  5. Seals in nuclear reactors

    International Nuclear Information System (INIS)

    1979-01-01

    The seals described are for use in a nuclear reactor where there are fuel assemblies in a vessel, an inlet and an outlet for circulating a coolant in heat transfer relationship with the fuel assemblies and a closure head on the vessel in a tight fluid relationship. The closure head comprises rotatable plugs which have mechanical seals disposed in the annulus around each plug while allowing free rotation of the plug when the seal is not actuated. The seal is usually an elastomer or copper. A means of actuating the seal is attached for drawing it vertically into the annulus for sealing. When the reactor coolant is liquid sodium, contact with oxygen must be avoided and argon cover gas fills the space between the bottom of the closure head and the coolant liquid level and the annuli in the closure head. (U.K.)

  6. Calculation of electron transmission through aluminium foil

    International Nuclear Information System (INIS)

    Abroyan, M.A.; Mel'ker, A.I.; Mikhajlin, A.I.; Sirotinkin, V.V.; Tokmakov, I.L.

    1987-01-01

    Calculated by Monte Carlo method energy and angular distributions of electrons transmitted through aluminium foil with 50 μm thickness are presented. 200-500 electron energy ranges and angles of electron incidence on foil from 0 to 40 deg C are considered. That allows to use results for more universal accelerator group, for example, for accelerators with scanning beam used in industry. The received values of angular and energy characteristics allow to increase essentially estimation accuracy of accelerator extraction devices and dose distribution on irradiating item

  7. Compressor ported shroud for foil bearing cooling

    Science.gov (United States)

    Elpern, David G [Los Angeles, CA; McCabe, Niall [Torrance, CA; Gee, Mark [South Pasadena, CA

    2011-08-02

    A compressor ported shroud takes compressed air from the shroud of the compressor before it is completely compressed and delivers it to foil bearings. The compressed air has a lower pressure and temperature than compressed outlet air. The lower temperature of the air means that less air needs to be bled off from the compressor to cool the foil bearings. This increases the overall system efficiency due to the reduced mass flow requirements of the lower temperature air. By taking the air at a lower pressure, less work is lost compressing the bearing cooling air.

  8. Spallation Neutron Source SNS Diamond Stripper Foil Development

    International Nuclear Information System (INIS)

    Shaw, Robert W.; Plum, Michael A.; Wilson, Leslie L.; Feigerle, Charles S.; Borden, Michael J.; Irie, Y.; Sugai, I.; Takagi, A.

    2007-01-01

    Diamond stripping foils are under development for the SNS. Freestanding, flat 300 to 500 (micro)g/cm 2 foils as large as 17 x 25 mm 2 have been prepared. These nano-textured polycrystalline foils are grown by microwave plasma-assisted chemical vapor deposition in a corrugated format to maintain their flatness. They are mechanically supported on a single edge by a residual portion of their silicon growth substrate; fine foil supporting wires are not required for diamond foils. Six foils were mounted on the SNS foil changer in early 2006 and have performed well in commissioning experiments at reduced operating power. A diamond foil was used during a recent experiment where 15 (micro)C of protons, approximately 64% of the design value, were stored in the ring. A few diamond foils have been tested at LANSCE/PSR, where one foil was in service for a period of five months (820 C of integrated injected charge) before it was replaced. Diamond foils have also been tested in Japan at KEK (640 keV H - ) where their lifetimes slightly surpassed those of evaporated carbon foils, but fell short of those for Sugai's new hybrid boron carbon (HBC) foils.

  9. Pressure actuated film riding seals for turbo machinery

    Science.gov (United States)

    Bidkar, Rahul Anil; Thatte, Azam Mihir; Gibson, Nathan Evan McCurdy; Giametta, Andrew Paul

    2015-08-25

    A seal assembly for a rotary machine is provided. The seal assembly includes multiple sealing device segments disposed circumferentially intermediate to a stationary housing and a rotor. Each of the sealing device segments includes a stator interface element, a shoe plate having an extended portion having one or more labyrinth teeth facing the rotor and a load bearing portion, wherein the shoe plate is configured to generate an aerodynamic force between the shoe plate and the rotor. The sealing device segment further includes a secondary seal configured to be in contact with the stator interface element at a radially outer end and configured to be in contact with an elevated nose section of the extended portion of the shoe plate on a radially inner end; and multiple flexible elements attached to the shoe plate and to the stator interface element.

  10. Seals in nuclear reactors

    International Nuclear Information System (INIS)

    1979-01-01

    The aim of this invention is the provision of improved seals for reactor vessels in which fuel assemblies are located together with inlets and outlets for the circulation of a coolant. The object is to provide a seal arrangement for the rotatable plugs of nuclear reactor closure heads which has good sealing capacities over a wide gap during operation of the reactor but which also permits uninhibited rotation of the plugs for maintenance. (U.K.)

  11. Seal containment system

    International Nuclear Information System (INIS)

    Kugler, R.W.; Gerkey, K.S.; Kasner, W.H.

    1978-01-01

    An automated system for transporting nuclear fuel elements between fuel element assembly stations without contaminating the area outside the sealed assembly stations is described. The system comprises a plurality of assembly stations connected together by an elongated horizontal sealing mechanism and an automatic transport mechanism for transporting a nuclear fuel element in a horizontal attitude between the assembly stations while the open end of the fuel element extends through the sealing mechanism into the assembly station enclosure. The sealing mechanism allows the fuel element to be advanced by the transport mechanism while limiting the escape of radioactive particles from within the assembly station enclosure. 4 claims, 6 figures

  12. Magnetic shaft seals prevent hazardous leakage from wastewater agitators

    International Nuclear Information System (INIS)

    Traino, F.A.

    1985-01-01

    The US Department of Energy's laboratory in Miamisburg, OH, operated by Monsanto Research Corporation, processes approximately 45,000 gallons per week of low-level radioactive wastewater to meet Federal Environmental Protection Agency quality standards. Preventing the spread of radioactive contamination throughout the operating area demands effective sealing of all process piping, valves, pumps, and agitators. Rotating shafts of pumps and agitators installed a the start of operations in 1947 were sealed by stuffing glands with graphite impregnated asbestos packing. These pumps proved to be unsatisfactory. In the mid-1970's, new process pumps with mechanical seals and some with magnetic drives were installed. Later, in January 1979, new agitator shaft drives with double tandem, spring-loaded mechanical seals were installed, maintenance of these pumps was costly. The agitator drive shafts were redesigned to accommodate magnetic seals of the type successfully used in blowers and vacuum/pressure pumps in other plant locations. One inherent advantage of the magnetic seal is that it operates with a face loading as much as 50% less than a conventional spring-loaded mechanical seal. The lower loading by a predetermined uniform magnetic force contributes to long face life. Other advantages include compactness, ease of assembly with only a few parts, and insensitivity to vibration. The magnetic shaft seals installed on the agitator shafts in February 1983 are still in service without any leakage or need for maintenance. Based on current operating data and a projected five-year meantime between failures, the estimated cost benefit of the magnetic seals over spring-loaded mechanical seals over spring-loaded mechanical seals will be $640 vs $2400 respectively per seal, with 60% less downtime for maintenance

  13. High Test Peroxide High Sealing Conical Seal, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — High Test Peroxide (HTP) Highly Compatible High Sealing Conical Seals are necessary for ground test operations and space based applications. Current conical seals...

  14. High pressure thimble/guide tube seal fitting with built-in low pressure seal especially suitable for facilitated and more efficient nuclear reactor refueling service

    International Nuclear Information System (INIS)

    Bhatt, P.N.; Blaushield, R.M.

    1991-01-01

    This patent describes a HP/LP seal arrangement for an elongated guide tube and an elongated thimble disposed therein. The guide tube and thimble extending outwardly from the core of a nuclear reactor to a seal table where the guide tube is welded to the seal table to provide a high pressure seal relative thereto. It comprises: a tubular seal fitting disposed in alignment with the guide tube with the thimble extending therethrough on the low pressure side of the seal table; first high pressure sealing means coupling one end of the fitting to an end of the guide tube to prevent leakage from within the guide tube; inwardly facing thread means disposed adjacent the other and outer end of the seal fitting; a nut having an opening through which the thimble extends and further having outwardly facing threading in mating engagement with the fitting thread means; the fitting having a seal seat spaced longitudinally inwardly from the thread means and facing the fitting outer end and further disposed annularly about the inner surface of the fitting; deformable ring seal means; second releasable high pressure sealing means coupling the thimble to the outer end portion of the guide tube

  15. Examination of the picture properties of luminescence memory foils

    International Nuclear Information System (INIS)

    Ewert, U.; Heine, S.; Nockemann, C.; Stade, J.; Tillack, G.R.; Wessel, H.; Zscherpel, U.; Mattis, A.

    1995-01-01

    Luminescence memory foils are a new medium for radiography without films. They are known by the name of image plates or digital memory foils. The suitability of such systems for industrial radiography is examined. (orig.) [de

  16. LENA Conversion Foils Using Single-Layer Graphene, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Our key innovation will be the use of single-layer graphene as LENA conversion foils, with appropriate microgrids and nanogrids to support the foils. Phase I...

  17. Face to Face

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 14; Issue 10. Turning a New Leaf H. Y. Mohan Ram talks to Sujata Varadarajan. H Y Mohan Ram Sujata Varadarajan. Face to Face Volume 14 Issue 10 October 2009 pp 1003-1017 ...

  18. Face to Face

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 20; Issue 3. Symmetry and Mathematics: Pioneering Insights into the Structure of Physics. Urjit A Yajnik. Face to Face Volume 20 Issue 3 March 2015 pp 264-276. Fulltext. Click here to view fulltext PDF. Permanent link:

  19. Face to Face

    DEFF Research Database (Denmark)

    Jungfalk, Michael; Rossen, Svend

    2008-01-01

    Blended learning in education is the combination of face‐to‐face seminars and on‐line work based on the internet. We have investigated which factors that we found were important in designing and conducting face‐to‐face seminars in order to facilitate learning processes in the periods of on...

  20. Face to Face

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 16; Issue 1. Do We Learn to See? Torsten Wiesel Prasanna Venkhatesh Venkataramani. Face to Face Volume 16 Issue 1 January 2011 pp 88-99. Fulltext. Click here to view fulltext PDF. Permanent link:

  1. Face to Face

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 19; Issue 5. Science is Not a Zero-Sum Game. Devendra Mani. Face to Face Volume 19 Issue 5 May 2014 pp 471-477. Fulltext. Click here to view fulltext PDF. Permanent link: https://www.ias.ac.in/article/fulltext/reso/019/05/0471-0477. Author Affiliations.

  2. Electronically controlled mechanical seal for aerospace applications--Part 2: Transient tests

    Science.gov (United States)

    Wolff, Paul J.; Salant, Richard F.

    1995-01-01

    An electronically controlled mechanical seal for use as the purge gas seal in a liquid oxygen turbopump has been fabricated and tested under transient operating conditions. The thickness of the lubricating film is controlled by adjusting the coning of the carbon face. This is accomplished by applying a voltage to a piezoelectric actuator to which the carbon face is bonded. The seal has been operated with a closed-loop control system that utilizes either the leakage rate or seal face temperature as the feedback. Both speed and pressure transients have been imposed on the seal. The transient tests have demonstrated that the seal is capable of maintaing low leakage rates while limiting face temperatures.

  3. Hydrogen and Palladium Foil: Two Classroom Demonstrations

    Science.gov (United States)

    Klotz, Elsbeth; Mattson, Bruce

    2009-01-01

    In these two classroom demonstrations, students observe the reaction between H[subscript 2] gas and Pd foil. In the first demonstration, hydrogen and palladium combine within one minute at 1 atm and room temperature to yield the non-stoichiometric, interstitial hydride with formula close to the maximum known value, PdH[subscript 0.7]. In the…

  4. 6Li foil thermal neutron detector

    Energy Technology Data Exchange (ETDEWEB)

    Ianakiev, Kiril D [Los Alamos National Laboratory; Swinhoe, Martyn T [Los Alamos National Laboratory; Favalli, Andrea [Los Alamos National Laboratory; Chung, Kiwhan [Los Alamos National Laboratory; Macarthur, Duncan W [Los Alamos National Laboratory

    2010-01-01

    In this paper we report on the design of a multilayer thermal neutron detector based on {sup 6}Li reactive foil and thin film plastic scintillators. The {sup 6}Li foils have about twice the intrinsic efficiency of {sup 10}B films and about four times higher light output due to a unique combination of high energy of reaction particles, low self absorption, and low ionization density of tritons. The design configuration provides for double sided readout of the lithium foil resulting in a doubling of the efficiency relative to a classical reactive film detector and generating a pulse height distribution with a valley between neutron and gamma signals similar to {sup 3}He tubes. The tens of microns thickness of plastic scintillator limits the energy deposited by gamma rays, which provides the necessary neutron/gamma discrimination. We used MCNPX to model a multilayer Li foil detector design and compared it with the standard HLNCC-II (18 {sup 3}He tubes operated at 4 atm). The preliminary results of the {sup 6}Li configuration show higher efficiency and one third of the die-away time. These properties, combined with the very short dead time of the plastic scintillator, offer the potential of a very high performance detector.

  5. The Fluid Foil: The Seventh Simple Machine

    Science.gov (United States)

    Mitts, Charles R.

    2012-01-01

    A simple machine does one of two things: create a mechanical advantage (lever) or change the direction of an applied force (pulley). Fluid foils are unique among simple machines because they not only change the direction of an applied force (wheel and axle); they convert fluid energy into mechanical energy (wind and Kaplan turbines) or vice versa,…

  6. Vortex wakes of a flapping foil

    DEFF Research Database (Denmark)

    Schnipper, Teis; Andersen, Anders Peter; Bohr, Tomas

    2009-01-01

    We present an experimental study of a symmetric foil performing pitching oscillations in a vertically flowing soap film. By varying the frequency and amplitude of the oscillation we visualize a variety of wakes with up to 46 vortices per oscillation period, including von Karman vortex street, inv...

  7. Thermal Sensitive Foils in Physics Experiments

    Science.gov (United States)

    Bochnícek, Zdenek; Konecný, Pavel

    2014-01-01

    The paper describes a set of physics demonstration experiments where thermal sensitive foils are used for the detection of the two dimensional distribution of temperature. The method is used for the demonstration of thermal conductivity, temperature change in adiabatic processes, distribution of electromagnetic radiation in a microwave oven and…

  8. Beam-foil study of neon in the EUV with foils of carbon, silver and gold

    International Nuclear Information System (INIS)

    Demarest, J.A.; Watson, R.L.; Texas A and M Univ., College Station

    1988-01-01

    A beam-foil study of 40 MeV neon was conducted in the EUV with a 1-meter grazing incidence spectrometer configured with a position sensitive microchannel plate detector. A number of new lines of Ne IX, mainly from transitions to n = 3 levels, were detected in the wavelength region covering 50-350 A. Comparison of the spectra obtained using the different foils revealed that the average charge state of the neon projectiles was nearly one unit higher with carbon than with either of the two metals. Measurements of line intensities versus distance from the foils showed that cascade contributions were greatly reduced for the metals. It was also found that n = 3 states of low l were overpopulated relative to a statistical distribution, irrespective of the foil material. (orig.)

  9. Identification of dynamic properties of radial air-foil bearings

    NARCIS (Netherlands)

    Arora, Vikas; Arora, V.; van der Hoogt, Peter; Aarts, Ronald G.K.M.; de Boer, Andries

    2010-01-01

    Air-foil bearings (AFBs) are self acting hydrodynamic bearings made from sheet metal foils comprised of at least two layers. The innermost “top foil” layer traps a gas pressure film that supports a load while the layer or layers underneath provide an elastic foundation. Air-foil bearings are

  10. Orientation and alignment in beam tilted-foil spectroscopy

    International Nuclear Information System (INIS)

    Berry, H.G.

    1976-01-01

    The production of atomic orientation and alignment, by anisotropic excitation is analyzed. The stokes parameters of the light emitted from tilted-foil excited ions provide measurements of orientation and alignment, and some examples are given. The variations of the stokes parameters with foil tilt angle, excited state, ion velocity and foil material are compared with existing theories

  11. Stripping foils for the PSB H- injection system

    CERN Document Server

    Aiba, M; Goddard, B; Weterings, W

    2009-01-01

    Beam physics considerations for the stripping foil of the PSB H- injection system are described, including the arguments for the foil type, thickness, geometry and positioning. The foil performance considerations are described, including expected stripping efficiency, emittance growth, energy straggling, temperature and lifetime. The required movement ranges and tolerances are detailed, together with the assumptions used.

  12. An investigative approach to explore optimum assembly process design for annular targets carrying LEU foil

    Science.gov (United States)

    Hoyer, Annemarie

    Technetium-99m is the most widely used nuclear isotope in the medical field, with nearly 80 to 85% of all diagnostic imaging procedures. The daughter isotope of molybdenum-99 is currently produced using weapons-grade uranium. A suggested design for aluminum targets carrying low-enriched uranium (LEU) foil is presented for the fulfillment of eliminating highly enriched uranium (HEU) for medical isotope production. The assembly process that this research focuses on is the conventional draw-plug process which is currently used and lastly the sealing process. The research is unique in that it is a systematic approach to explore the optimal target assembly process to produce those targets with the required quality and integrity. Conducting 9 parametric experiments, aluminum tubes with a nickel foil fission-barrier and a surrogate stainless steel foil are assembled, welded and then examined to find defects, to determine residual stresses, and to find the best cost-effective target dimensions. The experimental design consists of 9 assembly combinations that were found through orthogonal arrays in order to explore the significance of each factor. Using probabilistic modeling, the parametric study is investigated using the Taguchi method of robust analysis. Depending on the situation, optimal conditions may be a nominal, a minimized or occasionally a maximized condition. The results will provide the best target design and will give optimal quality with little or no assembly defects.

  13. Sealed radioactive sources toolkit

    International Nuclear Information System (INIS)

    Mac Kenzie, C.

    2005-09-01

    The IAEA has developed a Sealed Radioactive Sources Toolkit to provide information to key groups about the safety and security of sealed radioactive sources. The key groups addressed are officials in government agencies, medical users, industrial users and the scrap metal industry. The general public may also benefit from an understanding of the fundamentals of radiation safety

  14. Seals and Scrolls.

    Science.gov (United States)

    Macaulay, Sara Grove

    2000-01-01

    Describes an art unit in which students sculpt a signature seal out of clay and use Chinese brush painting techniques to paint a scroll. Discusses the seal and its historical use in China. Lists materials needed and explains the procedure. (CMK)

  15. Accessory components in gas-lubricated floating ring seals; Zusatzeinrichtungen an gasgeschmierten Gleitringdichtungen

    Energy Technology Data Exchange (ETDEWEB)

    Kirchner, C.; Victor, K.H.

    1995-12-31

    The present paper uses existing designs of floating-ring seal systems to illustrate their use as accessory components in gas-lubricated axial-face seals. These floating-ring seals may be used as pre-seals on the side of the axial-face seal facing the product. Here they are subject to high ambient pressure and small pressure differences. On the side of the axial-face seal facing the sliding bearing they are used as post-seals, where they are subject to atmospheric conditions and small pressure differences. The authors present various purpose-specific designs of these seal systems. Theoretical calculation models are compared with measuring results obtained under conditions close to actual practice. (orig.) [Deutsch] Anhand von ausgefuehrten Konstruktionen werden Schwimmring-Dichtungssysteme als Zusatzeinrichtung an gasgeschmierten Gleitringdichtungen (GLRD) erlaeutert. Auf der produktzugewandten Seite der GLRD werden diese Schwimmringdichtungen als Vordichtung (Pre-Seal) eingesetzt, die bei hohen Umgebungsdruecken und geringen Druckdifferenzen betrieben werden. Auf der dem Gleitlager zugewandten Seite der GLRD werden Schwimmringdichtungen bei atmosphaerischen Bedingungen und ebenfalls geringen Druckdifferenzen als nachgeschaltete Dichtung (Post-Seal) eingesetzt. Es werden konstruktive Loesungen fuer die verschiedenen Aufgaben dieser Dichtungssysteme vorgestellt. Theoretische Berechnungsmodelle werden mit praxisnahen Messergebnissen verglichen. (orig.)

  16. Miniature magnetic fluid seal working in liquid environments

    Science.gov (United States)

    Mitamura, Yoshinori; Durst, Christopher A.

    2017-06-01

    This study was carried out to develop a miniature magnetic fluid (MF) seal working in a liquid environment. The miniature MF seal is intended for use in a catheter blood pump. The requirements for the MF seal included a size of less than Ø4×4.5 mm, shaft diameter of 1 mm, sealing pressure of 200 mmHg, shaft speed of up to 40000 rpm, and life of one month. The miniature MF seal was composed of an NdFeB magnet (Ø4×Ø2×1) sandwiched between two pole pieces (Ø4×Ø1.1×0.5). A shield (Ø4×Ø1.2×1.5) was placed on the pole piece facing the liquid to minimize the influence of pump flow on the MF. The seal was installed on a Ø1 shaft. A seal was formed by injecting MF (Ms: 47.8 kA/m and η: 0.5 Pa·sec) into the gap between the pole pieces and the shaft. Total volume of the MF seal was 44 μL. A sealing pressure of 370 mmHg was obtained at motor speeds of 0-40,000 rpm. The seal remained perfect for 10 days in saline under the condition of a pump flow of 1.5 L/min (The test was terminated in accordance with plans). The seal remained intact after ethylene oxide sterilization during which the seal was exposed to high pressures. In conclusion, the newly developed MF seal will be useful for a catheter pump.

  17. Scaling laws for radial foil bearings

    Science.gov (United States)

    Honavara Prasad, Srikanth

    The effects of fluid pressurization, structural deformation of the compliant members and heat generation in foil bearings make the design and analysis of foil bearings very complicated. The complex fluid-structural-thermal interactions in foil bearings also make modeling efforts challenging because these phenomena are governed by highly non-linear partial differential equations. Consequently, comparison of various bearing designs require detailed calculation of the flow fields (velocities, pressures), bump deflections (structural compliance) and heat transfer phenomena (viscous dissipation in the fluid, frictional heating, temperature profile etc.,) resulting in extensive computational effort (time/hardware). To obviate rigorous computations and aid in feasibility assessments of foil bearings of various sizes, NASA developed the "rule of thumb" design guidelines for estimation of journal bearing load capacity. The guidelines are based on extensive experimental data. The goal of the current work is the development of scaling laws for radial foil bearings to establish an analytical "rule of thumb" for bearing clearance and bump stiffness. The use of scale invariant Reynolds equation and experimentally observed NASA "rule of thumb" yield scale factors which can be deduced from first principles. Power-law relationships between: a. Bearing clearance and bearing radius, and b. bump stiffness and bearing radius, are obtained. The clearance and bump stiffness values obtained from scaling laws are used as inputs for Orbit simulation to study various cases. As the clearance of the bearing reaches the dimensions of the material surface roughness, asperity contact breaks the fluid film which results in wear. Similarly, as the rotor diameter increases (requiring larger bearing diameters), the load capacity of the fluid film should increase to prevent dry rubbing. This imposes limits on the size of the rotor diameter and consequently bearing diameter. Therefore, this thesis aims

  18. Flexible Seal Accommodates Part Mismatch

    Science.gov (United States)

    Bobb, I.

    1983-01-01

    Chain of plates embedded in flexible seal enables it to withstand side loading of 2,300 psi (116MPa) while sealing gap of up to 0.5 inch (13 mm) between cylindrical chamber wall and test fixture. Pressure-actuated seal along inner edge forces seal into contact even though cylinder wall becomes eccentric as cylinder pressure increases. Seal has many industrial applications, particularly where heat or pressure causes distortion of chamber being sealed.

  19. Brush seal performance measurement system

    OpenAIRE

    Aksoy, Serdar; Akşit, Mahmut Faruk; Aksit, Mahmut Faruk; Duran, Ertuğrul Tolga; Duran, Ertugrul Tolga

    2009-01-01

    Brush seals are rapidly replacing conventional labyrinth seals in turbomachinery applications. Upon pressure application, seal stiffness increases drastically due to frictional bristle interlocking. Operating stiffness is critical to determine seal wear life. Typically, seal stiffness is measured by pressing a curved shoe to brush bore. The static-unpressurized measurement is extrapolated to pressurized and high speed operating conditions. This work presents a seal stiffness measurement syste...

  20. Reactor vessel sealing plug

    International Nuclear Information System (INIS)

    Dooley, R.A.

    1986-01-01

    An apparatus is described for sealing a cold leg nozzle of a nuclear reactor pressure vessel from a remote location comprising: at least one sealing plug for mechanically sealing the nozzle from the inside of the reactor pressure vessel. The sealing plug includes a plate and a cone assembly having an end part receptive in the nozzle, the plate being axially moveable relative to the cone assembly. The plate and cone assembly have confronting bevelled edges defining an opening therebetween. A primary O-ring is disposed about the opening and is supported on the bevelled edges, the plate being guidably mounted to the cone assembly for movement toward the cone assembly to radially expand the primary O-ring into sealing engagement with the nozzle. A means is included for providing relative movement between the outer plate and the cone assembly

  1. Novel Seals and Specialty Component Attachment Mechanisms for Respiratory Protection System (RESPO 21)

    Science.gov (United States)

    1992-10-01

    use in a warm clima ,, Ao~ hccts rovcf rur % Cr. ugc na il oimnte nber o prna in ntting materil coupled to skin separat lc~oe tect wocn f h~i. Sae...the mask shell on the side vagina and cervix of a woman in labor , electrode meam &h thereof facing the face. said sealing tube having a fixed sealed

  2. Carbon stripper foils held in place with carbon fibers

    International Nuclear Information System (INIS)

    Jolivet, Connie S.; Miller, Shawn A.; Stoner, John O.; Ladd, Peter

    2008-01-01

    The Spallation Neutron Source (SNS) currently under construction at Oak Ridge National Laboratory, Oak Ridge, Tennessee, is planned to initially utilize carbon stripper foils having areal densities approximately 260 μg/cm 2 . The projected design requires that each foil be supported by only one fixed edge. For stability of the foil, additional support is to be provided by carbon fibers. The feasibility of manufacturing and shipping such mounted carbon foils produced by arc evaporation was studied using two prototypes. Production of the foils is described. Fibers were chosen for satisfactory mechanical strength consistent with minimal interference with the SNS beam. Mounting of the fibers, and packaging of the assemblies for shipping are described. Ten completed assemblies were shipped to SNS for further testing. Preliminary evaluation of the survivability of the foils in the SNS foil changer is described

  3. Advances in targetry with thin diamond-like carbon foils

    CERN Document Server

    Liechtenstein, V K; Olshanski, E D; Repnow, R; Levin, J; Hellborg, R; Persson, P; Schenkel, T

    2002-01-01

    Thin and stable diamond-like carbon (DLC) foils, which were fabricated at the Kurchatov Institute by sputter deposition, have proved recently to be advantageous for stripping and secondary electron timing of high energy heavy ions in a number of accelerator experiments. This resulted in expanding applications of these DLC foils which necessitated further development efforts directed toward the following applications of DLC targetry: (i) thin stripper foils for lower energy tandem accelerators, (ii) enlarged (up to 66 mm in diameter) stop foils for improved time-of-flight elastic recoil detection ion beam analysis, and (iii) ultra-thin (about 0.6 mu g/cm sup 2) DLC foils for some fundamental and applied physics experiments. Along with the fabrication of thin DLC stripper foils for tandem accelerators, much thicker (up to 200 mu g/cm sup 2) foils for post-stripping of heavy-ion beams in higher energy linacs, are within reach.

  4. Mechanical Seal Opening Condition Monitoring Based on Acoustic Emission Technology

    Directory of Open Access Journals (Sweden)

    Erqing Zhang

    2014-06-01

    Full Text Available Since the measurement of mechanical sealing film thickness and just-lift-off time is very difficult, the sealing film condition monitoring method based on acoustic emission signal is proposed. The mechanical seal acoustic emission signal present obvious characteristics of time-varying nonlinear and pulsating. In this paper, the acoustic emission signal is used to monitor the seal end faces just-lift-off time and friction condition. The acoustic emission signal is decomposed by empirical mode decomposition into a series of intrinsic mode function with independent characteristics of different time scales and different frequency band. The acoustic emission signal only generated by end faces friction is obtained by eliminating the false intrinsic mode function components. The correlation coefficient of acoustic emission signal and Multi-scale Laplace Wavelet is calculated. It is proved that the maximum frequency (8000 Hz of the correlation coefficient is appeared at the spindle speed of 300 rpm. And at this time (300 rpm the end faces have just lifted off. By a set of mechanical oil seal running test, it is demonstrated that this method could accurately identify mechanical seal end faces just-lift-off time and friction condition.

  5. SEALING SIMULATED LEAKS

    Energy Technology Data Exchange (ETDEWEB)

    Michael A. Romano

    2004-09-01

    This report details the testing equipment, procedures and results performed under Task 7.2 Sealing Simulated Leaks. In terms of our ability to seal leaks identified in the technical topical report, Analysis of Current Field Data, we were 100% successful. In regards to maintaining seal integrity after pigging operations we achieved varying degrees of success. Internal Corrosion defects proved to be the most resistant to the effects of pigging while External Corrosion proved to be the least resistant. Overall, with limitations, pressure activated sealant technology would be a viable option under the right circumstances.

  6. Viscous investigation of a flapping foil propulsor

    Science.gov (United States)

    Posri, Attapol; Phoemsapthawee, Surasak; Thaweewat, Nonthipat

    2018-01-01

    Inspired by how fishes propel themselves, a flapping-foil device is invented as an alternative propulsion system for ships and boats. The performance of such propulsor has been formerly investigated using a potential flow code. The simulation results have shown that the device has high propulsive efficiency over a wide range of operation. However, the potential flow gives good results only when flow separation is not present. In case of high flapping frequency, the flow separation can occur over a short instant due to fluid viscosity and high angle of attack. This may cause a reduction of propulsive efficiency. A commercial CFD code based on Lattice Boltzmann Method, XFlow, is then employed in order to investigate the viscous effect over the propulsive performance of the flapping foil. The viscous results agree well with the potential flow results, confirming the high efficiency of the propulsor. As expected, viscous results show lower efficiency in high flapping frequency zone.

  7. Composite metal foil and ceramic fabric materials

    Science.gov (United States)

    Webb, Brent J.; Antoniak, Zen I.; Prater, John T.; DeSteese, John G.

    1992-01-01

    The invention comprises new materials useful in a wide variety of terrestrial and space applications. In one aspect, the invention comprises a flexible cloth-like material comprising a layer of flexible woven ceramic fabric bonded with a layer of metallic foil. In another aspect, the invention includes a flexible fluid impermeable barrier comprising a flexible woven ceramic fabric layer having metal wire woven therein. A metallic foil layer is incontinuously welded to the woven metal wire. In yet another aspect, the invention includes a material comprising a layer of flexible woven ceramic fabric bonded with a layer of an organic polymer. In still another aspect, the invention includes a rigid fabric structure comprising a flexible woven ceramic fabric and a resinous support material which has been hardened as the direct result of exposure to ultraviolet light. Inventive methods for producing such material are also disclosed.

  8. Brazing Inconel 625 Using the Copper Foil

    Science.gov (United States)

    Chen, Wen-Shiang; Wang, Cheng-Yen; Shiue, Ren-Kae

    2013-12-01

    Brazing Inconel 625 (IN-625) using the copper foil has been investigated in this research. The brazed joint is composed of nanosized CrNi3 precipitates and Cr/Mo/Nb/Ni quaternary compound in the Cu/Ni-rich matrix. The copper filler 50 μm in thickness is enough for the joint filling. However, the application of Cu foil 100 μm in thickness has little effect on the shear strength of the brazed joint. The specimen brazed at 1433 K (1160 °C) for 1800 seconds demonstrates the best shear strength of 470 MPa, and its fractograph is dominated by ductile dimple fracture with sliding marks. Decreasing the brazing temperature slightly decreases the shear strength of the brazed joint due to the presence of a few isolated solidification shrinkage voids smaller than 15 μm. Increasing the brazing temperature, especially for the specimen brazed at 1473 K (1200 °C), significantly deteriorates the shear strength of the joint below 260 MPa because of coalescence of isothermal solidification shrinkage voids in the joint. The Cu foil demonstrates potential in brazing IN-625 for industrial application.

  9. Sealing properties of mechanical seals for an axial flow blood pump.

    Science.gov (United States)

    Tomioka, J; Mori, T; Yamazaki, K; Koyanagi, H

    1999-08-01

    A miniature intraventricular axial flow blood pump for left ventricular support is under development. One of the key technologies required for such pumps is sealing of the motor shaft. In this study, to prevent blood backflow into the motor side, mechanical seals were developed and their sealing properties investigated. In the experimental apparatus, the mechanical seal separated the bovine blood on the chamber side from the cooling water on the motor side. A leakage of the blood was measured by inductively coupled plasma (ICP) light emission analysis. The rate of hemolysis was measured by the cyanmethemoglobin method. Frictional torque acting on the shaft was measured by a torque transducer. In the experiments, the rotational speed of the shaft was changed from 1,000 to 10,000 rpm, and the contact force of the seal faces was changed from 1.96 to 4.31 N. To estimate lubrication regimes, the Stribeck curve, a diagram of the coefficient of friction against the bearing characteristic G number, was drawn. The results of the experiments showed that both the leakage of blood and the rate of hemolysis were very small. The friction loss was also very small. The mechanical seal was operated in various lubrication regimes, from a fluid lubrication regime to a mixed lubrication regime.

  10. SRC seal testing

    Science.gov (United States)

    Miller, E. D.; Kohout, G. J.

    1973-01-01

    Small venthole drilled in semisealed silicon-controlled rectifier (SCR) cavity eliminates entrapped helium. Although these devices show slightly greater leak than those before lead installation, it is now possible to distinguish device with good hermetic seal from defective one.

  11. Turbine seal assembly

    Science.gov (United States)

    Little, David A.

    2013-04-16

    A seal assembly that limits gas leakage from a hot gas path to one or more disc cavities in a turbine engine. The seal assembly includes a seal apparatus that limits gas leakage from the hot gas path to a respective one of the disc cavities. The seal apparatus comprises a plurality of blade members rotatable with a blade structure. The blade members are associated with the blade structure and extend toward adjacent stationary components. Each blade member includes a leading edge and a trailing edge, the leading edge of each blade member being located circumferentially in front of the blade member's corresponding trailing edge in a direction of rotation of the turbine rotor. The blade members are arranged such that a space having a component in a circumferential direction is defined between adjacent circumferentially spaced blade members.

  12. [Sleep of Caspian seals].

    Science.gov (United States)

    Mukhametov, L M; Supin, A Ia; Poliakova, I G

    1984-01-01

    ECoG both hemispheres, EOG, neck EMG, ECG and electrical activity of olfactory bulbs were recorded in 4 free moving adult Caspean seals of both sexes. Their sleep on land and in water was compared. The wakefulness occupied 85,5 +/- 1,5% of total recording time, the slow wave sleep--12,8 +/- 1,4% and paradoxical sleep--1,7 +/- 0,2%. Unlike the dolphins, the Caspean seals possess no unihemispheric slow wave sleep. When the seals sleep on the land or on the water surface and do not change their posture for breathing they may breathe without awakening like the terrestrial mammals. But when the seals emerge or change their posture to get nostrils above the water they wake up briefly for respiration period.

  13. Core disruptive accident margin seal

    International Nuclear Information System (INIS)

    Golden, M.P.

    1979-01-01

    An apparatus for sealing the annulus defined within a substantially cylindrical rotatable riser assembly and plug combination of a nuclear reactor closure head is described. The apparatus comprises an inflatable sealing mechanism disposed in one portion of the riser assembly near the annulus such that upon inflation the sealing mechanism is radially actuated against the other portion of the riser assembly thereby sealing the annulus. The apparatus further comprises a connecting mechanism which places one end of the sealing mechanism in fluid communication with the reactor cover gas so that overpressurization of the reactor cover gas will increase the radial actuation of the sealing mechanism thus enhancing sealing of the annulus

  14. Ultra high vacuum seal arrangement

    Science.gov (United States)

    Flaherty, Robert

    1981-01-01

    Arrangement for demountably sealing two concentric metallic tubes in an ultra high vacuum system which facilitates remote actuation. A tubular seal includes integral spaced lips which circumferentially engage the metallic tubes. The lips plastically deform the metallic tubes by mechanical forces resulting from a martensite to austenite transformation of the tubular seal upon application of a predetermined temperature. The sealing force is released upon application of another temperature which causes a transformation from the stronger austenite to the weaker martensite. Use of a dual acting sealing ring and driving ring circumferentially contacting the sealing ring is particularly applicable to sealing larger diameter concentric metallic members.

  15. Titanium hermetic seals

    Science.gov (United States)

    Brow, Richard K.; Watkins, Randall D.

    1995-01-01

    Titanium is prenitrided by being heated in a nitrogen environment under conditions which give rise to the formation of a titanium-nitride surface layer on the titanium. Titanium thus prenitrided may be used in electrical components which are hermetically sealed using silicate glasses and standard glass sealing techniques. According to the method of the invention, alkali volatilization and formation of deleterious interfacial silicide are inhibited.

  16. A Gas Lubricant Combined Support-sealing Node

    Science.gov (United States)

    Falaleev, S. V.; Nadjari, H.; Vinogradov, A. S.

    2018-01-01

    The purpose of the research provided in this article is to develop a gas-dynamic device capable of performing the functions of support sealing, unloading devices for axial thrust bearings and damping of axial vibrations of the rotor. Some kinds of seals applied in supports of aircraft engines are known. A face gas-dynamic seal is one of the most effective and standard technology solution for compressors. As the basic element of the developed device, a face gas-dynamic seal with spiral grooves is considered. It also includes the fundamental mathematical calculation of such devices and the experimental research outcomes that form the basis of which such devices can be produced and adapted for use.

  17. Monitoring the degradation of partly decomposable plastic foils

    Directory of Open Access Journals (Sweden)

    Rétháti Gabriella

    2014-11-01

    Full Text Available We have monitored the behaviour of different polyethylene foils including virgin medium density polyethylene (MDPE, MDPE containing pro-oxydative additives (238, 242 and MDPE with pro-oxydative additives and thermoplastic starch (297 in the soil for a period of one year. A foil based on a blend of polyester and polylactic acid (BASF Ecovio served as degradable control. The experiment was carried out by weekly measurements of conductivity and capacity of the soil, since the setup was analogous to a condenser, of which the insulating layer was the foil itself. The twelve replications allowed monthly sampling; the specimen taken out from the soil each month were tested visually for thickness, mechanical properties, morphological and structural changes, and molecular mass. Based on the obtained capacity values, we found that among the polyethylene foils, the one that contained thermoplastic starch extenuated the most. This foil had the greatest decrease in tensile strength and elongation at break due to the presence of thermoplastic starch. The starch can completely degrade in the soil; thus, the foil had cracks and pores. The polyethylene foils that contained pro-oxydant additives showed smaller external change compared to the virgin foil, since there was no available UV radiation and oxygen for their degradation. The smallest change occurred in the virgin polyethylene foil. Among the five examined samples, the commercially available BASF foil showed the largest extenuation and external change, and it deteriorated the most in the soil.

  18. Foil changer for the Chalk River superconducting cyclotron

    International Nuclear Information System (INIS)

    Hoffmann, C.R.; Kilborn, R.I.; Mouris, J.E.; Proulx, D.R.; Weaver, J.F.

    1985-01-01

    Capture of an injected beam in the Chalk River superconducting cyclotron requires that a carbon stripping foil be accurately placed in a dee to intercept the incoming beam. Foil radial position must be precisely adjustable and foils must be easily replaced. A foil changing apparatus has been designed, built and tested to meet these requirements. The main components are a supply magazine, a transport system, and unloading and loading mechanisms. The magazine is on top of the cyclotron. It holds 300 foils and can be isolated from machine vacuum for refilling. Each foil is mounted on a stainless steel frame. A stainless steel roller chain fitted with 33 copper sleeves (shrouds) carries foils, one per shroud, down a dee stem to the midplane. A 12-bit absolute optical shaft encoder senses foil position. To replace a foil a shroud is positioned at the top of the cyclotron, a foil is removed, and another is transferred from the magazine to the empty shroud. Three stepping motors and associated electronics provide mechanical drive and are interfaced with a CAMAC control system

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

    Science.gov (United States)

    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

  20. Serum chemistry and antibodies against pathogens in antarctic fur seals, Weddell seals, crabeater seals, and Ross seals.

    Science.gov (United States)

    Tryland, Morten; Nymo, Ingebjørg H; Nielsen, Ole; Nordøy, Erling S; Kovacs, Kit M; Krafft, Bjørn A; Thoresen, Stein I; Åsbakk, Kjetil; Osterrieder, Klaus; Roth, Swaantje J; Lydersen, Christian; Godfroid, Jacques; Blix, Arnoldus S

    2012-07-01

    Information on health parameters, such as antibody prevalences and serum chemistry that can reveal exposure to pathogens, disease, and abnormal physiologic conditions, is scarce for Antarctic seal species. Serum samples from Antarctic fur seals (Arctocephalus gazella, n=88) from Bouvetøya (2000-2001 and 2001-2002), and from Weddell seals (Leptonychotes weddellii, n=20), Ross seals (Ommatophoca rossii, n=20), and crabeater seals (Lobodon carcinophagus, n=9) from the pack-ice off Queen Maud Land, Antarctica (2001) were analyzed for enzyme activity, and concentrations of protein, metabolites, minerals, and cortisol. Adult Antarctic fur seal males had elevated levels of total protein (range 64-99 g/l) compared to adult females and pups (range 52-79 g/l). Antarctic fur seals had higher enzyme activities of creatine kinase, lactate dehydrogenase, and amylase, compared to Weddell, Ross, and crabeater seals. Antibodies against Brucella spp. were detected in Weddell seals (37%), Ross seals (5%), and crabeater seals (11%), but not in Antarctic fur seals. Antibodies against phocine herpesvirus 1 were detected in all species examined (Antarctic fur seals, 58%; Weddell seals, 100%; Ross seals, 15%; and crabeater seals, 44%). No antibodies against Trichinella spp., Toxoplasma, or phocine distemper virus (PDV) were detected (Antarctic fur seals were not tested for PDV antibodies). Antarctic seals are challenged by reduced sea ice and increasing temperatures due to climate change, and increased anthropogenic activity can introduce new pathogens to these vulnerable ecosystems and represent a threat for these animals. Our data provide a baseline for future monitoring of health parameters of these Antarctic seal species, for tracking the impact of environmental, climatic, and anthropogenic changes in Antarctica over time.

  1. Upgrading inflatable door seals

    International Nuclear Information System (INIS)

    Sykes, T.M.; Metcalfe, R.; Welch, L.A.; Josefowich, J.M.

    1997-01-01

    Inflatable door seals are used for airlocks in CANDU stations. They have been a significant source of unreliability and maintenance cost. A program is underway to improve their performance and reliability, backed by environmental qualification testing. Only commercial products and suppliers existed in 1993. For historical reasons, these 'existing products' did not use the most durable material then available. In hindsight, neither had they been adapted nor optimized to combat conditions often experienced in the plants-sagging doors, damaged sealing surfaces, and many thousands of openings and closings per year. Initial attempts to involve the two existing suppliers in efforts to upgrade these seals were unsuccessful. Another suitable supplier had therefore to be found, and a 'new,' COG-owned seal developed; this was completed in 1997. This paper summarizes its testing, along with that of the two existing products. Resistance to aging has been improved significantly. Testing has shown that an accident can be safely withstood after 10 years of service or 40,000 openings-closings, whichever comes first. AECL's Fluid Sealing Technology Unit (FSTU) has invested in the special moulds, test fixtures and other necessary tooling and documentation required to begin commercial manufacture of this new quality product. Accordingly, as with FSTU's other nuclear products such as pump seals, the long-term supply of door seals to CANDU plants is now protected from many external uncertainties-e.g., commercial products being discontinued, materials being changed, companies going out of business. Manufacturing to AECL's detailed specifications is being subcontracted to the new supplier. FSTU is performing the quality surveillance, inspection, testing, and customer service activities concomitant with direct responsibility for supply to the plants. (author)

  2. Method of forming a thin unbacked metal foil

    Science.gov (United States)

    Duchane, David V.; Barthell, Barry L.

    1984-01-01

    In a method of forming a thin (foil having a desired curviplanar shape, a soluble polymeric film, preferably comprising polyvinyl alcohol, is formed on a supporting structure having a shape that defines the desired shape of the foil product. A layer of metal foil is deposited onto one side of the soluble film, preferably by vacuum vapor deposition. The metallized film is then immersed in a suitable solvent to dissolve the film and thereby leave the metal foil as an unbacked metal foil element mounted on the supporting structure. Aluminum foils less than 0.2 .mu.m (2,000 .ANG.) thick and having an areal density of less than 54 .mu.g/cm.sup.2 have been obtained.

  3. Extreme extensibility of copper foil under compound forming conditions.

    Science.gov (United States)

    Yu, Qingbo; Liu, Xianghua; Tang, Delin

    2013-12-19

    A copper foil with an extreme extensibility up to 43,684% was obtained without any intermediate annealing by means of asynchronous rolling with high tension. It was found that under the combination of compression, shearing and tension, the copper foil represents a wonderful phenomenon. As the reduction increases, the specimen hardness increases up to a peak value 138 HV0.05 when the foil thickness rolled to around 100 μm, and then it decreases down to 78 HV0.05 when the foil thickness rolled to the final size 19 μm. It tells us that the strain-softening effect occurs when the foil thickness is rolled down to a threshold level. The experimental results bring us some fresh ideas different with the traditional understanding on the strain-hardening mechanism of metals, which provides an experimental basis to establish the forming mechanism of the thin foil.

  4. Effects of Aluminum Foil Packaging on Elemental Analysis of Bone.

    Science.gov (United States)

    Lewis, Lyniece; Christensen, Angi M

    2016-03-01

    Burned skeletal material is often very fragile and at high risk for fragmentation during packaging and transportation. One method that has been suggested to protect bones in these cases is to carefully wrap them in aluminum foil. Traces of aluminum, however, are known to transfer from foil packaging materials to food products. If such transfer occurs between aluminum foil and bones, it could interfere with subsequent chemical, elemental and isotopic analyses, which are becoming more common in forensic anthropological investigations. This study examined aluminum levels in bones prior to and following the use of aluminum foil packaging and storage for a 6-week period. Results indicate no significant change in the detected levels of aluminum (p > 0.05), even when packaged in compromised foil and exposed to elevated temperatures. Aluminum foil can therefore continue to be recommended as a packaging medium without affecting subsequent chemical examinations. © 2015 American Academy of Forensic Sciences.

  5. Microfabricated Segmented-Involute-Foil Regenerator for Stirling Engines

    Science.gov (United States)

    Ibrahim, Mounir; Danila, Daniel; Simon, Terrence; Mantell, Susan; Sun, Liyong; Gedeon, David; Qiu, Songgang; Wood, Gary; Kelly, Kevin; McLean, Jeffrey

    2010-01-01

    An involute-foil regenerator was designed, microfabricated, and tested in an oscillating-flow test rig. The concept consists of stacked involute-foil nickel disks (see figure) microfabricated via a lithographic process. Test results yielded a performance of about twice that of the 90-percent random-fiber currently used in small Stirling converters. The segmented nature of the involute- foil in both the axial and radial directions increases the strength of the structure relative to wrapped foils. In addition, relative to random-fiber regenerators, the involute-foil has a reduced pressure drop, and is expected to be less susceptible to the release of metal fragments into the working space, thus increasing reliability. The prototype nickel involute-foil regenerator was adequate for testing in an engine with a 650 C hot-end temperature. This is lower than that required by larger engines, and high-temperature alloys are not suited for the lithographic microfabrication approach.

  6. Stresses in the foil of an electron accelerator extraction channel

    International Nuclear Information System (INIS)

    Abroyan, M.A.; Makarenko, T.I.; Tokmakov, I.L.

    1983-01-01

    Stresses in the foil of an electron accelerator extraction channel are assessed with account of contributions of thermal expansion and stress concentrations during switchings. Optimization of extraction grid parameters of the electron accelerator extraction channel and choice of foil material for high current electron beam is conducted. It is suggested that an extraction grid with circular cells and Al-Mg foil should be used. A simple formula applicable for design calculations is proposed for evaluation of stress concentration coefficient during phase switchings

  7. Forged seal detection based on the seal overlay metric.

    Science.gov (United States)

    Lee, Joong; Kong, Seong G; Lee, Young-Soo; Moon, Ki-Woong; Jeon, Oc-Yeub; Han, Jong Hyun; Lee, Bong-Woo; Seo, Joong-Suk

    2012-01-10

    This paper describes a method for verifying the authenticity of a seal impression imprinted on a document based on the seal overlay metric, which refers to the ratio of an effective seal impression pattern and the noise in the neighborhood of the reference impression region. A reference seal pattern is obtained by taking the average of a number of high-quality impressions of a genuine seal. A target seal impression to be examined, often on paper with some background texts and lines, is segmented out from the background by an adaptive threshold applied to the histogram of color components. The segmented target seal impression is then spatially aligned with the reference by maximizing the count of matching pixels. Then the seal overlay metric is computed for the reference and the target. If the overlay metric of a target seal is below a predetermined limit for the similarity to the genuine, then the target is classified as a forged seal. To further reduce the misclassification rate, the seal overlay metric is adjusted by the filling rate, which reflects the quality of inked pattern of the target seal. Experiment results demonstrate that the proposed method can detect elaborate seal impressions created by advanced forgery techniques such as lithography and computer-aided manufacturing. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  8. Characterization of U-Mo Foils for AFIP-7

    Energy Technology Data Exchange (ETDEWEB)

    Edwards, Danny J.; Ermi, Ruby M.; Schemer-Kohrn, Alan L.; Overman, Nicole R.; Henager, Charles H.; Burkes, Douglas; Senor, David J.

    2012-11-07

    Twelve AFIP in-process foil samples, fabricated by either Y-12 or LANL, were shipped from LANL to PNNL for potential characterization using optical and scanning electron microscopy techniques. Of these twelve, nine different conditions were examined to one degree or another using both techniques. For this report a complete description of the results are provided for one archive foil from each source of material, and one unirradiated piece of a foil of each source that was irradiated in the Advanced Test Reactor. Additional data from two other LANL conditions are summarized in very brief form in an appendix. The characterization revealed that all four characterized conditions contained a cold worked microstructure to different degrees. The Y-12 foils exhibited a higher degree of cold working compared to the LANL foils, as evidenced by the highly elongated and obscure U-Mo grain structure present in each foil. The longitudinal orientations for both of the Y-12 foils possesses a highly laminar appearance with such a distorted grain structure that it was very difficult to even offer a range of grain sizes. The U-Mo grain structure of the LANL foils, by comparison, consisted of a more easily discernible grain structure with a mix of equiaxed and elongated grains. Both materials have an inhomogenous grain structure in that all of the characterized foils possess abnormally coarse grains.

  9. Note: the influence of exploding foil shape on energy deposition.

    Science.gov (United States)

    Zeng, Qingxuan; Lv, Junjun; Li, Mingyu

    2013-06-01

    The main influence factors of exploding bridge foil were studied in order to improve energy utilization of the explosion foil initiator. "Square" and "curving" shaped bridge foils were fabricated using magnetron sputtering and chemical etching techniques, and the key dimension of the bridge foil was measured using surface profiler. Commercial software MATLAB was employed to calculate the burst current, burst voltage, and energy deposition. Simulation results were in good agreement with experiment data. In this study, the energy deposition ratio of "square" shaped bridge is between 45%-50%, while the value of "curving" shaped bridge is between 55%-75%.

  10. LENA Conversion Foils Using Single-Layer Graphene, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Implementing graphene foils in existing neutral atom detector designs will increase their angular and energy resolution, and also improve their mass discrimination...

  11. Foil focusing of relativistic electron beams

    Energy Technology Data Exchange (ETDEWEB)

    Ekdahl, Jr., Carl August [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-10-26

    When an intense relativistic electron beams (IREB) passes through a grounded metal foil, the transverse electric field due to the beam space charge is locally shorted out, and the beam is focused by the magnetic field of its current. The effect can be treated as focusing by a thin lens with first order aberration. Expressions for the focal length and aberration coefficient of the equivalent thin lens are developed in this note. These are then applied to practical examples representative of IREB research at Los Alamos National Laboratory.

  12. The Los Alamos foil implosion project

    International Nuclear Information System (INIS)

    Brownell, J.; Parker, J.; Bartsch, R.; Benage, J.; Bowers, R.; Cochrane, J.; Forman, P.; Goforth, J.; Greene, A.; Kruse, H.

    1993-01-01

    The goal of the Los Alamos foil implosion project is to produce an intense (>100 TW), multi-megajoule, laboratory soft x-ray source for material studies and fusion experiments. The concept involves the implosion of annular, current-carrying, cylindrical metallic plasmas via their self-magnetic forces. The project features inductive storage systems using both capacitor banks and high explosive-driven flux compression generators as prime energy sources. Fast opening switches are employed to shorten the electrical pulses. The program will be described and activities to date will be summarized

  13. Pool gateway seal

    International Nuclear Information System (INIS)

    Starr, J.A.; Steinert, L.A.

    1983-01-01

    A device for sealing a gateway between interconnectable pools in a nuclear facility comprising a frame supporting a liquid impermeable sheet positioned in a u-shaped gateway between the pools. An inflatable tube carried in a channel in the periphery of the frame and adjoining the gateway provides a seal therebetween when inflated. A restraining arrangement on the bottom edge of the frame is releasably engagable with an adjacent portion of the gateway to restrict the movement of the frame in the u-shaped gateway upon inflation of the tube, thereby enhancing the seal. The impermeable sheet is formed of an elastomer and thus is conformable to a liquid permeable supportive wall upon application of liquid pressure to the side of the sheet opposite the wall

  14. HMSRP Hawaiian Monk Seal Master Identification Records (seal)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains records of all individually identified Hawaiian monk seals since 1981. These seals were identified by PSD personnel and cooperating scientists...

  15. Structural Design and Sealing Performance Analysis of Biomimetic Sealing Ring

    Directory of Open Access Journals (Sweden)

    Chuanjun Han

    2015-01-01

    Full Text Available In order to reduce the failure probability of rubber sealing rings in reciprocating dynamic seal, a new structure of sealing ring based on bionics was designed. The biomimetic ring has three concave ridges and convex bulges on each side which are very similar to earthworms. Bulges were circularly designed and sealing performances of the biomimetic ring in both static seal and dynamic seal were simulated by FEM. In addition, effects of precompression, medium pressure, speed, friction coefficient, and material parameters on sealing performances were discussed. The results show that von Mises stress of the biomimetic sealing ring distributed symmetrically in no-pressure static sealing. The maximum von Mises stress appears on the second bulge of the inner side. High contact stress concentrates on left bulges. Von Mises stress distribution becomes uneven under medium pressure. Both von Mises stress and contact stress increase when precompression, medium pressure, and rubber hardness increase in static sealing. Biomimetic ring can avoid rolling and distortion in reciprocating dynamic seal, and its working life is much longer than O-ring and rectangular ring. The maximum von Mises stress and contact stress increase with the precompression, medium pressure, rubber hardness, and friction coefficient in reciprocating dynamic seal.

  16. Actinide Foil Production for MPACT Research

    Energy Technology Data Exchange (ETDEWEB)

    Beller, Denis

    2012-10-30

    Sensitive fast-neutron detectors are required for use in lead slowing down spectrometry (LSDS), an active interrogation technique for used nuclear fuel assay for Materials Protection, Accounting, and Controls Technologies (MPACT). During the past several years UNLV sponsored a research project at RPI to investigate LSDS; began development of fission chamber detectors for use in LSDS experiments in collaboration with INL, LANL, and Oregon State U.; and participated in a LSDS experiment at LANL. In the LSDS technique, research has demonstrated that these fission chamber detectors must be sensitive to fission energy neutrons but insensitive to thermal-energy neutrons. Because most systems are highly sensitive to large thermal neutron populations due to the well-known large thermal cross section of 235U, even a miniscule amount of this isotope in a fission chamber will overwhelm the small population of higher-energy neutrons. Thus, fast-fission chamber detectors must be fabricated with highly depleted uranium (DU) or ultra-pure thorium (Th), which is about half as efficient as DU. Previous research conducted at RPI demonstrated that the required purity of DU for assay of used nuclear fuel using LSDS is less than 4 ppm 235U, material that until recently was not available in the U.S. In 2009 the PI purchased 3 grams of ultra-depleted uranium (uDU, 99.99998% 238U with just 0.2 ± 0.1 ppm 235U) from VNIIEF in Sarov, Russia. We received the material in the form of U3O8 powder in August of 2009, and verified its purity and depletion in a FY10 MPACT collaboration project. In addition, chemical processing for use in FC R&D was initiated, fission chamber detectors and a scanning alpha-particle spectrometer were developed, and foils were used in a preliminary LSDS experiment at a LANL/LANSCE in Sept. of 2010. The as-received U3O8 powder must be chemically processed to convert it to another chemical form while maintaining its purity, which then must be used to electro-deposit U

  17. Static seal for turbine engine

    Science.gov (United States)

    Salazar, Santiago; Gisch, Andrew

    2014-04-01

    A seal structure for a gas turbine engine, the seal structure including first and second components located adjacent to each other and forming a barrier between high and low pressure zones. A seal cavity is defined in the first and second components, the seal cavity extending to either side of an elongated gap extending generally in a first direction between the first and second components. A seal member is positioned within the seal cavity and spans across the elongated gap. The seal member includes first and second side edges extending into each of the components in a second direction transverse to the first direction, and opposing longitudinal edges extending between the side edges generally parallel to the first direction. The side edges include a groove formed therein for effecting a reduction of gas flow around the seal member at the side edges.

  18. Magnetically Actuated Seal, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — FTT proposes development of a magnetically actuated dynamic seal. Dynamic seals are used throughout the turbopump in high-performance, pump-fed, liquid rocket...

  19. Magnetically Actuated Seal, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — FTT proposes development of a magnetically actuated dynamic seal. Dynamic seals are used throughout the turbopump in high-performance, pump-fed, liquid rocket...

  20. Continuous improvement of pump seals

    International Nuclear Information System (INIS)

    Wong, W.; Eyvindson, A.; Rhodes, D.B.

    2003-01-01

    Pump seal reliability continues to be an area needing improvement and ongoing vigilance. Methods have been developed for identifying and assessing factors relating to seal performance, selecting the most relevant ones for a specific station, and then focusing on the most significant aspects and how to improve. Discussion invariably addresses maintenance practices, seal design, monitoring capabilities, operating conditions, transients, and pump and motor design. Success in reliability improvement requires ongoing dialogue among the station operators, pump manufacturers and seal designers. AECL CAN-seals lead the nuclear industry in reliability and seal life. They effectively save operators millions of dollars in outage time and person-rem. This paper describes some of the significant developments in AECL's ongoing program in seal R and D, as well as recent new installations following the most demanding seal qualification programs to date. (author)

  1. Axial seal system for a gas turbine steam-cooled rotor

    Science.gov (United States)

    Mashey, Thomas Charles

    2002-01-01

    An axial seal assembly is provided at the interface between adjacent wheels and spacers of a gas turbine rotor and disposed about tubes passing through openings in the rotor adjacent the rotor rim and carrying a thermal medium. Each seal assembly includes a support bushing for supporting a land of the thermal medium carrying tube, an axially registering seat bushing disposed in the opposed opening and a frustoconical seal between the seal bushing and seat. The seal bushing includes a radial flange having an annular recess for retaining the outer diameter edge of the seal, while the seat bushing has an axially facing annular surface forming a seat for engagement by the inner diameter edge of the seal.

  2. GOLD PRESSURE VESSEL SEAL

    Science.gov (United States)

    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)

  3. Four Sided Seal Tester

    Science.gov (United States)

    2009-07-01

    The Center for Advanced Food Technology School of Enviromental and Biological Sciences New Brunswick, NJ 08903 FTR 216 Defense Logistics Agency...specification for four sided seal tester as function of confinement plate distance” The following modifications were issued :  Jul 18, 2007 0013/01

  4. Detection of grey seal

    NARCIS (Netherlands)

    van Bleijswijk, J.; Begeman, L.; Witte, H.J.; IJsseldijk, L.L.; Brasseur, S.M.J.M.; Gröne, A.; Leopold, M.F.

    2014-01-01

    DNA was analysed from external wounds on 3 dead harbour porpoises Phocoena phocoena that were stranded in the Netherlands. Puncture wounds as well as the edges of large open wounds were sampled with sterile cotton swabs. With specific primers that target the mtDNA control region of grey seal

  5. Design and optimization of vertex detector foils by superplastic forming

    NARCIS (Netherlands)

    Snippe, Q.H.C.

    2011-01-01

    The production of one of the parts in a particle detector, called the RF Foil, has been a very intensive process in the past. The design and production process, which had a trial and error character, led eventually to an RF Foil that met the most important requirement: a sufficient leak tightness

  6. Foil fabrication for the ROMANO event. Revision 1

    International Nuclear Information System (INIS)

    Romo, J.G. Jr.; Weed, J.W.; Griggs, G.E.; Brown, T.G.; Tassano, P.L.

    1984-01-01

    The Vacuum Processes Lab (VPL), of LLNL's M.E. Dept. - Material Fabrication Division (MFD), conducted various vacuum related support activities for the ROMANO nuclear physics experiment. This report focuses on the foil fabrication activities carried out between July and November 1983 for the ROMANO event. Other vacuum related activities for ROMANO, such as outgassing tests of materials, are covered in separate documentation. VPL was asked to provide 270 coated Parylene foils for the ROMANO event. However, due to the developmental nature of some of the procedures, approximately 400 coated foils were processed. In addition, VPL interacted with MFD's Plastics Shop to help supply Parylene substrates to other organizations (i.e., LBL and commercial vendors) which had also been asked to provide coated foils for ROMANO. The purposes of this report are (A) to document the processes developed and the techniques used to produce the foils, and (B) to suggest future directions. The report is divided into four sections describing: (1) nuclear target foil fabrication, (2) Parylene substrate preparation and production, (3) calibration foil fabrication, and (4) foil and substrate inspections

  7. Practical and research aspects of beam-foil spectroscopy

    International Nuclear Information System (INIS)

    Bashkin, S.

    1974-01-01

    Practical aspects of the application of low-energy accelerators to research in beam-foil spectroscopy are discussed, and the kinds of equipment and associated costs are described in some detail. Some typical beam-foil experiments, emphasizing the most recent studies, are treated so as to show how relatively simple facilities can be used to produce physics of great interest

  8. Lithographic patterning of metals on flexible plastic foils

    NARCIS (Netherlands)

    Peter, M.; Furthner, F.; Deen, J.; Laat, W.J.M.de; Meinders, E.R.

    2009-01-01

    In this paper the challenges of patterning electrodes with separations in the micron and sub-micron range onto thin polyethylene naphthalate foils for use in biochips are discussed. It was found that it was necessary to improve the adhesion of the metal electrodes to the foil by using plasma

  9. Ultrasonic dip seal maintenance system

    International Nuclear Information System (INIS)

    Poindexter, A.M.; Ricks, H.E.

    1978-01-01

    Disclosed is a system for removing impurities from the surfaces of liquid dip seals and for wetting the metal surfaces of liquid dip seals in nuclear components. The system comprises an ultrasonic transducer that transmits ultrasonic vibrations along an ultrasonic probe to the metal and liquid surfaces of the dip seal thereby loosening and removing those impurities

  10. Characterization of the water diffusion in GEM foil material

    Science.gov (United States)

    Benussi, L.; Bianco, S.; Saviano, G.; Muhammad, S.; Piccolo, D.; Raffone, G.; Caponero, M.; Passamonti, L.; Pierluigi, D.; Russo, A.; Primavera, F.; Cerbelli, S.; Lalli, A.; Valente, M.; Ferrini, M.; Teissandier, B.; Taborelli, M.; Parvis, M.; Grassini, S.; Tirilló, J.; Sarasini, F.; Franchi, A. V.

    2018-02-01

    Systematic studies on the GEM foil material are performed to measure the moisture diffusion rate and saturation level. These studies are important because the presence of this compound inside the detector' s foil can possibly change its mechanical and electrical properties, and in such a way, the detector performance can be affected. To understand this phenomenon, a model is developed with COMSOL Multiphysics v. 4.3 [1], which described the adsorption and diffusion within the geometry of GEM foil, the concentration profiles and the time required to saturate the foil. The COMSOL model is verified by experimental observations on a GEM foil sample. This note will describe the model and its experimental verification results.

  11. Gas Foil Bearing Misalignment and Unbalance Effects

    Science.gov (United States)

    Howard, Samuel A.

    2008-01-01

    The effects of misalignment and unbalance on gas foil bearings are presented. The future of U.S. space exploration includes plans to conduct science missions aboard space vehicles, return humans to the Moon, and place humans on Mars. All of these endeavors are of long duration, and require high amounts of electrical power for propulsion, life support, mission operations, etc. One potential source of electrical power of sufficient magnitude and duration is a nuclear-fission-based system. The system architecture would consist of a nuclear reactor heat source with the resulting thermal energy converted to electrical energy through a dynamic power conversion and heat rejection system. Various types of power conversion systems can be utilized, but the Closed Brayton Cycle (CBC) turboalternator is one of the leading candidates. In the CBC, an inert gas heated by the reactor drives a turboalternator, rejects excess heat to space through a heat exchanger, and returns to the reactor in a closed loop configuration. The use of the CBC for space power and propulsion is described in more detail in the literature (Mason, 2003). In the CBC system just described, the process fluid is a high pressure inert gas such as argon, krypton, or a helium-xenon mixture. Due to the closed loop nature of the system and the associated potential for damage to components in the system, contamination of the working fluid is intolerable. Since a potential source of contamination is the lubricant used in conventional turbomachinery bearings, Gas Foil Bearings (GFB) have high potential for the rotor support system. GFBs are compliant, hydrodynamic journal and thrust bearings that use a gas, such as the CBC working fluid, as their lubricant. Thus, GFBs eliminate the possibility of contamination due to lubricant leaks into the closed loop system. Gas foil bearings are currently used in many commercial applications, both terrestrial and aerospace. Aircraft Air Cycle Machines (ACMs) and ground

  12. Thin foil expansion into a vacuum

    International Nuclear Information System (INIS)

    Mora, P.

    2005-01-01

    Plasma expansion into a vacuum is an old problem which has been renewed recently in various contexts: expansion of ultra-cold plasmas, cluster expansion, of dust grains, expansion of thin foils. In this presentation I will first discuss the physics of the expansion of a thin foil irradiated by an ultra-short ultra-intense laser pulse. The expansion results in the formation of high energy ions. For an infinitely steep plasma-vacuum interface the fastest ions are located in the outer part of the expansion and their velocity is given by ν m ax∼ 2 C s (In ω p it) where c s (Zk B T e /m i )''1/2 is the ion-acoustic velocity ω p i=(n e 0Ze''2/m i e 0 )''1/2 is the ion plasma frequency, n e 0 is the electron density in the unperturbed plasma, Z is the ion charge number. In the above expression, t is either the pulse duration or the effective acceleration time (in particular t∼L/2c s , where L is the width of the foil, when the electron cooling is taken into account). A salient characteristic of the expansion is the occurrence of a double layer structure and a peak of the accelerating electric field at the ion front. I will explain the origin of the peak and predict its temporal behavior. This peak has been diagnosed in recent experiments. I will also discuss the effect of a 2-temperatures electron distribution function on the expansion, showing the dominant role of the hot electron component. Finally I will discuss the occurrence of ion spikes in the expansion when the initial density profile is smooth. The ion spike is due to a wave breaking which cannot be handled in a satisfactory way by a fluid code and requires a kinetic description. A. simple collisionless particle code has been used to treat the evolution of the spike after the wave breaking and the results will be shown. (Author)

  13. Nanocrystalline diamond coatings for mechanical seals applications.

    Science.gov (United States)

    Santos, J A; Neto, V F; Ruch, D; Grácio, J

    2012-08-01

    A mechanical seal is a type of seal used in rotating equipment, such as pumps and compressors. It consists of a mechanism that assists the connection of the rotating shaft to the housings of the equipments, preventing leakage or avoiding contamination. A common cause of failure of these devices is end face wear out, thus the use of a hard, smooth and wear resistant coating such as nanocrystalline diamond would be of great importance to improve their working performance and increase their lifetime. In this paper, different diamond coatings were deposited by the HFCVD process, using different deposition conditions. Additionally, the as-grown films were characterized for, quality, morphology and microstructure using scanning electron microscopy (SEM) and Raman spectroscopy. The topography and the roughness of the films were characterized by atomic force microscopy (AFM).

  14. Elastomer seal for a large toroidal vacuum chamber

    International Nuclear Information System (INIS)

    Skellett, S.; Casey, F.; Blake, H.

    1978-07-01

    An aluminium toroidal vacuum chamber for use at 10(-6) torr, whose overall diameter is in the region of 5 metres, was built from 4 component parts which resulted in joint lines in the horizontal and vertical planes crossing each other in 4 places. A viton seal was developed which allows a vacuum tight joint to be made without the need for tightly toleranced fitting of the mating faces and also overcomes the difficulty of ensuring a reliable seal at cross-over joints. Ease of maintenance and repair in situ are important factors of the design. An assembly which presented the geometry of the sealing problem was tested and is described here. Various adhesives for bonding viton were examined for the manufacture of the seal. The most suitable adhesive was found to be Loctite S496, chosen for its bond strength and convenience in use. A device for preparing and bonding the viton in situ is described. (author)

  15. Design considerations for foil windows for PET radioisotope targets

    International Nuclear Information System (INIS)

    Hughey, B.J.; Shefer, R.E.; Klinkowstein, R.E.; Welch, M.J.

    1992-01-01

    This paper describes the results of a study performed at SRL to develop analytical and computational techniques for optimizing the design of conduction-cooled foil windows for PET targets. Single foil conduction cooled windows have been found to be good target entrance windows for both low energy accelerators and medium energy cyclotrons. Detailed thermal analysis has given an approximate analytical expression for the maximum temperature reached in a foil window under conditions of realistic ion beam bombardment. The effects of 'hot spots' in the beam density profile were investigated. It was shown that a factor of two safety margin in window design should be adequate to compensate for any possible beam hot spots. In addition, the reduction of foil stress by slack mounting was verified by experiments. The properties of conventional and novel foil materials were investigated for use in conduction cooled windows. Novel foil materials include two-component Al/Ti and Al/Havar foil. Results on the testing of candidate foil materials for thermal conductivity and mechanical strength at elevated temperature were presented. Two optimum foil window geometries were analyzed: a high aspect ratio window and a multiply slotted window. The multiply slotted window combines the advantages of a high aspect ratio foil window with a circular beam strike and is a promising window design for both TCA and cyclotron targets. A multiply slotted window for a N 2 gas target for 15 O production was designed using the methodologies discussed above. This prototype target was successfully tested using the TCA beam at SRL. (author) 6 figs., 3 tabs., 10 refs

  16. High strain rate metalworking with vaporizing foil actuator: control of flyer velocity by varying input energy and foil thickness.

    Science.gov (United States)

    Vivek, A; Hansen, S R; Daehn, Glenn S

    2014-07-01

    Electrically driven rapid vaporization of thin metallic foils can generate a high pressure which can be used to launch flyers at high velocities. Recently, vaporizing foil actuators have been applied toward a variety of impulse-based metal working operations. In order to exercise control over this useful tool, it is imperative that an understanding of the effect of characteristics of the foil actuator on its ability for mechanical impulse generation is developed. Here, foil actuators made out of 0.0508 mm, 0.0762 mm, and 0.127 mm thick AA1145 were used for launching AA2024-T3 sheets of thickness 0.508 mm toward a photonic Doppler velocimeter probe. Launch velocities ranging between 300 m/s and 1100 m/s were observed. In situ measurement of velocity, current, and voltage assisted in understanding the effect of burst current density and deposited electrical energy on average pressure and velocity with foil actuators of various thicknesses. For the pulse generator, geometry, and flyer used here, the 0.0762 mm thick foil was found to be optimal for launching flyers to high velocities over short distances. Experimenting with annealed foil actuators resulted in no change in the temporal evolution of flyer velocity as compared to foil actuators of full hard temper. A physics-based analytical model was developed and found to have reasonable agreement with experiment.

  17. Gulf and Dilmun Type seals

    DEFF Research Database (Denmark)

    Laursen, Steffen

    2011-01-01

    From around 2100 BC a glyptic tradition emerges in the Arabian Gulf, which is dependant on the well-established schools of the Indus Valley seal cutters. These circular hybrids of classic Harappan seals rapidly became popular amongst the merchants of Dilmun, centered on Bahrain Island. At first...... these Gulf Type‘ seals drew heavily on Indus Valley iconography and Indus script was occasionally employed in a pidgin-like manner. While the earliest circular seals incorporate features from Mesopotamian glyptic only to a lesser extent, this becomes a more important source of inspiration for later Dilmun...... Type seals....

  18. {beta}-nmr of Palladium foil

    Energy Technology Data Exchange (ETDEWEB)

    Parolin, T.J. [Department of Chemistry, University of British Columbia, Vancouver, BC, V6T 1Z1 (Canada); Salman, Z. [TRIUMF, 4004 Wesbrook Mall, Vancouver, BC, V6T 2A3 (Canada); Chakhalian, J. [Max-Plank Institute for Solid State Research, D-70569 Stuttgart (Germany); Wang, D. [Department of Physics and Astronomy, University of British Columbia, Vancouver, BC, V6T 1Z1 (Canada); Keeler, T.A. [Department of Physics and Astronomy, University of British Columbia, Vancouver, BC, V6T 1Z1 (Canada); Hossain, Md. [Department of Physics and Astronomy, University of British Columbia, Vancouver, BC, V6T 1Z1 (Canada); Kiefl, R.F. [TRIUMF, 4004 Wesbrook Mall, Vancouver, BC, V6T 2A3 (Canada); Department of Physics and Astronomy, University of British Columbia, Vancouver, BC, V6T 1Z1 (Canada); Canadian Institute for Advanced Research (Canada); Chow, K.H. [Department of Physics, University of Alberta, Edmonton, AB, T6G 2J1 (Canada); Morris, G.D. [TRIUMF, 4004 Wesbrook Mall, Vancouver, BC, V6T 2A3 (Canada); Miller, R.I. [TRIUMF, 4004 Wesbrook Mall, Vancouver, BC, V6T 2A3 (Canada); MacFarlane, W.A. [Department of Chemistry, University of British Columbia, Vancouver, BC, V6T 1Z1 (Canada)]. E-mail: wam@chem.ubc.ca

    2006-03-31

    Beta-detected NMR ({beta}-nmr) of low-energy implanted {sup 8}Li{sup +} was studied in metallic palladium. The resonance was found to have a large negative shift with respect to the reference signal in the cubic insulator MgO. This shift exhibited significant temperature dependence on cooling below room temperature, approximately proportionate to the temperature-dependent spin susceptibility of pure Pd. Thus it is tentatively attributed to a Knight shift (K) caused by a large negative hyperfine coupling; a phenomenon common in transition metal ions, but not in alkalis. However, the spin-lattice relaxation of {sup 8}Li is much slower than expected from the Korringa law for such a large K. We compare results from samples of very different thicknesses: 12.5{mu}m foil and a 100nm thin film.

  19. Large-area beryllium metal foils

    Science.gov (United States)

    Stoner, J. O., Jr.

    1997-02-01

    To manufacture beryllium filters having diameters up to 82 mm and thicknesses in the range 0.1-1 μm, it was necessary to construct apparatus in which the metal could safely be evaporated, and then to find an acceptable substrate and evaporation procedure. The metal was evaporated resistively from a tantalum dimple boat mounted in a baffled enclosure that could be placed in a conventional vacuum bell jar, obviating the need for a dedicated complete vacuum system. Substrates were 102 mm × 127 mm × 0.05 mm cleaved mica sheets, coated with 0.1 μm of NaCl, then with approximately 50 μg/cm 2 of cellulose nitrate. These were mounted on poly(methyl methacrylate) sheets 3 mm thick that were in turn clamped to a massive aluminum block for thermal stability. Details of the processes for evaporation, float off, and mounting are given, and the resulting foils described.

  20. Preparation of selenium coatings onto beryllium foils

    International Nuclear Information System (INIS)

    Erikson, E.D.; Tassano, P.L.; Reiss, R.H.; Griggs, G.E.

    1984-09-01

    A technique for preparing selenium films onto 50.8 microns thick beryllium foils is described. The selenium was deposited in vacuum from a resistance heated evaporation source. Profilometry measurements of the coatings indicate deposit thicknesses of 5.5, 12.9, 37.5, 49.8 and 74.5 microns. The control of deposition rate and of coating thickness was facilitated using a commercially available closed-loop programmable thin film controller. The x-ray transmission of the coated substrates was measured using a tritiated zirconium source. The transmissivities of the film/substrate combination are presented for the range of energies from 4 to 20 keV. 15 references, 3 figures

  1. Evidence for age-related performance degradation of (241)Am foil sources commonly used in UK schools.

    Science.gov (United States)

    Whitcher, R; Page, R D; Cole, P R

    2014-06-01

    The characteristics of alpha radiation have for decades been demonstrated in UK schools using small sealed (241)Am sources. There is a small but steady number of schools who report a considerable reduction in the alpha count rate detected by an end-window GM detector compared with when the source was new. This cannot be explained by incorrect apparatus or set-up, foil surface contamination, or degradation of the GM detector. The University of Liverpool and CLEAPSS collaborated to research the cause of this performance degradation. The aim was to find what was causing the performance degradation and the ramifications for both the useful and safe service life of the sources. The research shows that these foil sources have greater energy straggling with a corresponding reduction in spectral peak energy. A likely cause for this increase in straggling is a significant diffusion of the metals over time. There was no evidence to suggest the foils have become unsafe, but precautionary checks should be made on old sources.

  2. Polarity influence on the indentation punching of thin {111} GaAs foils at elevated temperatures

    International Nuclear Information System (INIS)

    Patriarche, G; Largeau, L; Riviere, J P; Bourhis, E Le

    2005-01-01

    Thin {111} GaAs substrates were deformed by a Vickers indenter at 350 deg. C-370 deg. C under loads ranging between 0.4 and 1.9 N. Optical microscopy and interferometry were used to observe the indented and opposite faces of the thin foils and hence to investigate the plastic flow through the samples. Attention was paid to the polarity (A or B) of the specimen surface, as GaAs is known to show a large difference between α and β dislocations mobilities. A model considering the influence of polarity is proposed to describe the material flow throughout thin samples

  3. Hermetic Seal Leak Detection Apparatus

    Science.gov (United States)

    Kelley, Anthony R. (Inventor)

    2013-01-01

    The present invention is a hermetic seal leak detection apparatus, which can be used to test for hermetic seal leaks in instruments and containers. A vacuum tight chamber is created around the unit being tested to minimize gas space outside of the hermetic seal. A vacuum inducing device is then used to increase the gas chamber volume inside the device, so that a slight vacuum is pulled on the unit being tested. The pressure in the unit being tested will stabilize. If the stabilized pressure reads close to a known good seal calibration, there is not a leak in the seal. If the stabilized pressure reads closer to a known bad seal calibration value, there is a leak in the seal. The speed of the plunger can be varied and by evaluating the resulting pressure change rates and final values, the leak rate/size can be accurately calculated.

  4. Seals Having Textured Portions for Protection in Space Environments

    Science.gov (United States)

    Daniels, Christopher (Inventor); Garafolo, Nicholas (Inventor)

    2016-01-01

    A sealing construct for a space environment includes a seal-bearing object, a seal on the seal-bearing object, and a seal-engaging object. The seal includes a seal body having a sealing surface, and a textured pattern at the sealing surface, the textured pattern defining at least one shaded channel surface. The seal-engaging object is selectively engaged with the seal-bearing object through the seal. The seal-engaging object has a sealing surface, wherein, when the seal-engaging object is selectively engaged with the seal-bearing object, the sealing surface of the seal-engaging object engages the sealing surface of the seal, and the seal is compressed between the seal-bearing object and the seal-engaging object such that at least one shaded channel surface engages the sealing surface of the seal-engaging object.

  5. Radioactive waste sealing container

    International Nuclear Information System (INIS)

    Tozawa, S.; Kitamura, T.; Sugimoto, S.

    1984-01-01

    A low- to medium-level radioactive waste sealing container is constructed by depositing a foundation coating consisting essentially of zinc, cadmium or a zinc-aluminum alloy over a steel base, then coating an organic synthetic resin paint containing a metal phosphate over the foundation coating, and thereafter coating an acryl resin, epoxy resin, and/or polyurethane paint. The sealing container can consist of a main container body, a lid placed over the main body, and fixing members for clamping and fixing the lid to the main body. Each fixing member may consist of a material obtained by depositing a coating consisting essentially of cadmium or a zinc-aluminum alloy over a steel base

  6. Compliant Foil Journal Bearing Performance at Alternate Pressures and Temperatures

    Science.gov (United States)

    Bruckner, Robert J.; Puleo, Bernadette J.

    2008-01-01

    An experimental test program has been conducted to determine the highly loaded performance of current generation gas foil bearings at alternate pressures and temperatures. Typically foil bearing performance has been reported at temperatures relevant to turbomachinery applications but only at an ambient pressure of one atmosphere. This dearth of data at alternate pressures has motivated the current test program. Two facilities were used in the test program, the ambient pressure rig and the high pressure rig. The test program utilized a 35 mm diameter by 27 mm long foil journal bearing having an uncoated Inconel X-750 top foil running against a shaft with a PS304 coated journal. Load capacity tests were conducted at 3, 6, 9, 12, 15, 18, and 21 krpm at temperatures from 25 to 500 C and at pressures from 0.1 to 2.5 atmospheres. Results show an increase in load capacity with increased ambient pressure and a reduction in load capacity with increased ambient temperature. Below one-half atmosphere of ambient pressure a dramatic loss of load capacity is experienced. Additional lightly loaded foil bearing performance in nitrogen at 25 C and up to 48 atmospheres of ambient pressure has also been reported. In the lightly loaded region of operation the power loss increases for increasing pressure at a fixed load. Knowledge of foil bearing performance at operating conditions found within potential machine applications will reduce program development risk of future foil bearing supported turbomachines.

  7. Electromagnetic shaft seal

    International Nuclear Information System (INIS)

    Takahashi, Kenji.

    1994-01-01

    As an electromagnetic shaft seal, there are disposed outwarding electromagnetic induction devices having generating power directing to an electroconductive fluid as an object of sealing, and inwarding electromagnetic induction device added coaxially. There are disposed elongate rectangular looped first coils having a predetermined inner diameter, second coils having the same shape and shifted by a predetermined pitch relative to the first coil and third coil having the same shape and shifted by a predetermined pitch relative to the second coil respectively each at a predetermined inner diameter of clearance to the outwarding electromagnetic induction devices and the inwarding electromagnetic induction device. If the inwarding electromagnetic induction device and the outwarding electromagnetic induction device are operated, they are stopped at a point that the generating power of the former is equal with the sum of the generating power of the latter and a differential pressure. When three-phase AC is charged to the first coil, the second coil and the third coil successively, a force is generated in the advancing direction of the magnetic field in the electroconductive fluid by the similar effect to that of a linear motor, and the seal is maintained at high reliability. Moreover, the limit for the rotational angle of the shaft is not caused. (N.H.)

  8. Rolling and pitching oscillating foil propulsion in ground effect.

    Science.gov (United States)

    Perkins, Matthew D; Elles, Dane; Badlissi, George; Mivehchi, Amin; Dahl, Jason; Licht, Stephen

    2017-09-04

    In this paper, we investigate the effect of operating near a solid boundary on the forces produced by harmonically oscillating thrust generating foils. A rolling and pitching foil was towed in a freshwater tank in a series of experiments with varying kinematics. Hydrodynamic forces and torques were measured in the free stream and at varying distances from a solid boundary, and changes in mean lift and thrust were found when the foil approached the boundary. The magnitude of this ground effect exhibited a strong nonlinear dependence on the distance between the foil and the boundary. Significant effects were found within three chord lengths of the boundary, and ground effect can be induced at greater distances from the boundary by biasing the tip of the foil toward the boundary. Lift coefficients changed by as much as 0.2 at the closest approach to the ground, with changes ≥0.05 for all cases across Strouhal number ranging from 0.3 to 0.6, and nominal maximum angle of attack ranging from 20° to 40°. The ubiquity of the ground effect in high thrust kinematics suggests that the ground effect can provide a passive obstacle avoidance capability for foil propelled vehicles. By comparison to previous experimental work, we find that the ground effect experienced by a high-aspect ratio rolling and pitching foil is a fully three-dimensional phenomenon, as it is not accurately predicted when two-dimensional flow and/or two-dimensional kinematics are enforced. While two dimensional foil kinematics are more easily modeled for numerical studies, three-dimensional foil kinematics may be more practical for real world implementation in underwater vehicles. © 2017 IOP Publishing Ltd.

  9. Quantified Faces

    DEFF Research Database (Denmark)

    Sørensen, Mette-Marie Zacher

    2016-01-01

    Abstract: The article presents three contemporary art projects that, in various ways, thematise questions regarding numerical representation of the human face in relation to the identification of faces, for example through the use of biometric video analysis software, or DNA technology. The Dutch...... artist Marnix de Nijs' Physiognomic Scrutinizer is an interactive installation whereby the viewer's face is scanned and identified with historical figures. The American artist Zach Blas' project Fag Face Mask consists of three-dimensional portraits that blend biometric facial data from 30 gay men's faces...

  10. A novel carbon coating technique for foil bolometers.

    Science.gov (United States)

    Sheikh, U A; Duval, B P; Labit, B; Nespoli, F

    2016-11-01

    Naked foil bolometers can reflect a significant fraction of incident energy and therefore cannot be used for absolute measurements. This paper outlines a novel coating approach to address this problem by blackening the surface of gold foil bolometers using physical vapour deposition. An experimental bolometer was built containing four standard gold foil bolometers, of which two were coated with 100+ nm of carbon. All bolometers were collimated and observed the same relatively high temperature, ohmically heated plasma. Preliminary results showed 13%-15% more incident power was measured by the coated bolometers and this is expected to be much higher in future TCV detached divertor experiments.

  11. Preparation of self-supporting metallic foils of nickel isotopes

    International Nuclear Information System (INIS)

    Sugai, Isao.

    1975-01-01

    This is the fourth report on the practical methods of target preparation for use in low energy nuclear experiments following the previous one (INS-J-150). An electroplating method has been developed as a dependable and reproducible technique for making self-supporting metallic foils of nickel in the thickness range of 0.5 to 10 mg/cm 2 . The procedures minimized the necessary amount of material so that nickel isotopes could be processed economically. Impurity contamination of the nickel foils during the electroplating process was less than 500 ppm, and the thickness variation in each foil was less than 3% of the central thickness. (auth.)

  12. Elevated Temperature Tensile Tests on DU–10Mo Rolled Foils

    Energy Technology Data Exchange (ETDEWEB)

    Schulthess, Jason [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2014-09-01

    Tensile mechanical properties for uranium-10 wt.% molybdenum (U–10Mo) foils are required to support modeling and qualification of new monolithic fuel plate designs. It is expected that depleted uranium-10 wt% Mo (DU–10Mo) mechanical behavior is representative of the low enriched U–10Mo to be used in the actual fuel plates, therefore DU-10Mo was studied to simplify material processing, handling, and testing requirements. In this report, tensile testing of DU-10Mo fuel foils prepared using four different thermomechanical processing treatments were conducted to assess the impact of foil fabrication history on resultant tensile properties.

  13. Method of fabricating a uranium-bearing foil

    Science.gov (United States)

    Gooch, Jackie G [Seymour, TN; DeMint, Amy L [Kingston, TN

    2012-04-24

    Methods of fabricating a uranium-bearing foil are described. The foil may be substantially pure uranium, or may be a uranium alloy such as a uranium-molybdenum alloy. The method typically includes a series of hot rolling operations on a cast plate material to form a thin sheet. These hot rolling operations are typically performed using a process where each pass reduces the thickness of the plate by a substantially constant percentage. The sheet is typically then annealed and then cooled. The process typically concludes with a series of cold rolling passes where each pass reduces the thickness of the plate by a substantially constant thickness amount to form the foil.

  14. Closure and Sealing Design Calculation

    International Nuclear Information System (INIS)

    T. Lahnalampi; J. Case

    2005-01-01

    The purpose of the ''Closure and Sealing Design Calculation'' is to illustrate closure and sealing methods for sealing shafts, ramps, and identify boreholes that require sealing in order to limit the potential of water infiltration. In addition, this calculation will provide a description of the magma that can reduce the consequences of an igneous event intersecting the repository. This calculation will also include a listing of the project requirements related to closure and sealing. The scope of this calculation is to: summarize applicable project requirements and codes relating to backfilling nonemplacement openings, removal of uncommitted materials from the subsurface, installation of drip shields, and erecting monuments; compile an inventory of boreholes that are found in the area of the subsurface repository; describe the magma bulkhead feature and location; and include figures for the proposed shaft and ramp seals. The objective of this calculation is to: categorize the boreholes for sealing by depth and proximity to the subsurface repository; develop drawing figures which show the location and geometry for the magma bulkhead; include the shaft seal figures and a proposed construction sequence; and include the ramp seal figure and a proposed construction sequence. The intent of this closure and sealing calculation is to support the License Application by providing a description of the closure and sealing methods for the Safety Analysis Report. The closure and sealing calculation will also provide input for Post Closure Activities by describing the location of the magma bulkhead. This calculation is limited to describing the final configuration of the sealing and backfill systems for the underground area. The methods and procedures used to place the backfill and remove uncommitted materials (such as concrete) from the repository and detailed design of the magma bulkhead will be the subject of separate analyses or calculations. Post-closure monitoring will not

  15. TECHNOLOGY ROADMAPPING FOR IAEA SEALS.

    Energy Technology Data Exchange (ETDEWEB)

    HOFFHEINS,B.; ANNESE,C.; GOODMAN,M.; OCONNOR,W.; GUSHUE,S.; PEPPER,S.

    2003-07-13

    In the fall of 2002, the U.S. Support Program (USSP) initiated an effort to define a strategy or ''roadmap'' for future seals technologies and to develop a generalized process for planning safeguards equipment development, which includes seals and other safeguards equipment. The underlying objectives of the USSP include becoming more proactive than reactive in addressing safeguards equipment needs, helping the IAEA to maintain an inventory of cost-effective, reliable, and effective safeguards equipment, establishing a long-term planning horizon, and securing IAEA ownership in the process of effective requirements definition and timely transitioning of new or improved systems for IAEA use. At an initial workshop, seals, their functions, performance issues, and future embodiments were discussed in the following order: adhesive seals, metal seals, passive and active loop seals, ultrasonic seals, tamper indicating enclosures (including sample containers, equipment enclosures, and conduits). Suggested improvements to these technologies focused largely on a few themes: (1) The seals must be applied quickly, easily, and correctly; (2) Seals and their associated equipment should not unduly add bulk or weight to the inspectors load; (3) Rapid, in-situ verifiability of seals is desirable; and (4) Seal systems for high risk or high value applications should have two-way, remote communications. Based upon these observations and other insights, the participants constructed a skeletal approach for seals technology planning. The process begins with a top-level review of the fundamental safeguards requirements and extraction of required system features, which is followed by analysis of suitable technologies and identification of technology gaps, and finally by development of a planning schedule for system improvements and new technology integration. Development of a comprehensive procedure will require the partnership and participation of the IAEA. The

  16. TECHNOLOGY ROADMAPPING FOR IAEA SEALS

    International Nuclear Information System (INIS)

    HOFFHEINS, B.; ANNESE, C.; GOODMAN, M.; OCONNOR, W.; GUSHUE, S.; PEPPER, S.

    2003-01-01

    In the fall of 2002, the U.S. Support Program (USSP) initiated an effort to define a strategy or ''roadmap'' for future seals technologies and to develop a generalized process for planning safeguards equipment development, which includes seals and other safeguards equipment. The underlying objectives of the USSP include becoming more proactive than reactive in addressing safeguards equipment needs, helping the IAEA to maintain an inventory of cost-effective, reliable, and effective safeguards equipment, establishing a long-term planning horizon, and securing IAEA ownership in the process of effective requirements definition and timely transitioning of new or improved systems for IAEA use. At an initial workshop, seals, their functions, performance issues, and future embodiments were discussed in the following order: adhesive seals, metal seals, passive and active loop seals, ultrasonic seals, tamper indicating enclosures (including sample containers, equipment enclosures, and conduits). Suggested improvements to these technologies focused largely on a few themes: (1) The seals must be applied quickly, easily, and correctly; (2) Seals and their associated equipment should not unduly add bulk or weight to the inspectors' load; (3) Rapid, in-situ verifiability of seals is desirable; and (4) Seal systems for high risk or high value applications should have two-way, remote communications. Based upon these observations and other insights, the participants constructed a skeletal approach for seals technology planning. The process begins with a top-level review of the fundamental safeguards requirements and extraction of required system features, which is followed by analysis of suitable technologies and identification of technology gaps, and finally by development of a planning schedule for system improvements and new technology integration. Development of a comprehensive procedure will require the partnership and participation of the IAEA. The presentation will include a

  17. Air-stable and freestanding lithium alloy/graphene foil as an alternative to lithium metal anodes.

    Science.gov (United States)

    Zhao, Jie; Zhou, Guangmin; Yan, Kai; Xie, Jin; Li, Yuzhang; Liao, Lei; Jin, Yang; Liu, Kai; Hsu, Po-Chun; Wang, Jiangyan; Cheng, Hui-Ming; Cui, Yi

    2017-10-01

    Developing high-capacity anodes is a must to improve the energy density of lithium batteries for electric vehicle applications. Alloy anodes are one promising option, but without pre-stored lithium, the overall energy density is limited by the low-capacity lithium metal oxide cathodes. Recently, lithium metal has been revived as a high-capacity anode, but faces several challenges owing to its high reactivity and uncontrolled dendrite growth. Here, we show a series of Li-containing foils inheriting the desirable properties of alloy anodes and pure metal anodes. They consist of densely packed Li x M (M = Si, Sn, or Al) nanoparticles encapsulated by large graphene sheets. With the protection of graphene sheets, the large and freestanding Li x M/graphene foils are stable in different air conditions. With fully expanded Li x Si confined in the highly conductive and chemically stable graphene matrix, this Li x Si/graphene foil maintains a stable structure and cyclability in half cells (400 cycles with 98% capacity retention). This foil is also paired with high-capacity Li-free V 2 O 5 and sulfur cathodes to achieve stable full-cell cycling.

  18. Air-stable and freestanding lithium alloy/graphene foil as an alternative to lithium metal anodes

    Science.gov (United States)

    Zhao, Jie; Zhou, Guangmin; Yan, Kai; Xie, Jin; Li, Yuzhang; Liao, Lei; Jin, Yang; Liu, Kai; Hsu, Po-Chun; Wang, Jiangyan; Cheng, Hui-Ming; Cui, Yi

    2017-10-01

    Developing high-capacity anodes is a must to improve the energy density of lithium batteries for electric vehicle applications. Alloy anodes are one promising option, but without pre-stored lithium, the overall energy density is limited by the low-capacity lithium metal oxide cathodes. Recently, lithium metal has been revived as a high-capacity anode, but faces several challenges owing to its high reactivity and uncontrolled dendrite growth. Here, we show a series of Li-containing foils inheriting the desirable properties of alloy anodes and pure metal anodes. They consist of densely packed LixM (M = Si, Sn, or Al) nanoparticles encapsulated by large graphene sheets. With the protection of graphene sheets, the large and freestanding LixM/graphene foils are stable in different air conditions. With fully expanded LixSi confined in the highly conductive and chemically stable graphene matrix, this LixSi/graphene foil maintains a stable structure and cyclability in half cells (400 cycles with 98% capacity retention). This foil is also paired with high-capacity Li-free V2O5 and sulfur cathodes to achieve stable full-cell cycling.

  19. Troubleshooting ProSeal LMA

    Directory of Open Access Journals (Sweden)

    Bimla Sharma

    2009-01-01

    Full Text Available Supraglottic devices have changed the face of the airway management. These devices have contributed in a big way in airway management especially, in the difficult airway scenario significantly decreasing the pharyngolaryngeal morbidity. There is a plethora of these devices, which has been well matched by their wider acceptance in clinical practice. ProSeal laryngeal mask airway (PLMA is one such frequently used device employed for spontaneous as well as controlled ventilation. However, the use of PLMAat tunes maybe associated with certain problems. Some of the problems related with its use are unique while others are akin to the classic laryngeal mask airway (eLMA. However, expertise is needed for its safe and judicious use, correct placement, recognition and management of its various malpositions and complications. The present article describes the tests employed for proper confirmation of placementto assess the ventilatooy and the drain tube functions of the mask, diagnosis of various malpositions and the management of these aspects. All these areas have been highlighted under the heading of troubleshooting PLMA. Many problems can be solved by proper patient and procedure selection, maintaining adequate depth of anaesthesia, diagnosis and management of malpositions. Proper fixation of the device and monitoring cuff pressure intraopera-tively may bring down the incidence of airway morbidity.

  20. ESDRED Temporary Sealing Technology Final Technical Report

    Energy Technology Data Exchange (ETDEWEB)

    Alonso, J.; Garcia-Sineriz, J. L.; Barcena, I.; Alonso, M. C.; Fernandez Luco, L.; Garcia, J. L.; Fries, T.; Pettersson, S.; Boden, A.; Salo, J. P.

    2009-07-01

    The work in the ESDRED In te grated Project Module 4, Temporary Sealing (using low pH cement) Technology, consisted first of designing a low pH cement formulation and then of preparing several concrete designs suitable for the construction of sealing plugs and for rock support using shot crete techniques. Regarding sealing plugs, a short plug was constructed at Aspo in Sweden and it was very quickly loaded to failure i.e. slippage by applying water pressure to one face. A second, full scale plug was subsequently constructed at Grimsel test site in Switzerland. It was loaded using the swelling pressure created by bentonite blocks which were artificially hydrated. At time of writing the targeted pressure on the plug was not reached. As the saturation of the bentonite is taking longer than expected the partners involved agreed to continue with the saturation of the bentonite blocks and the related data monitoring beyond the ESDRED Project. The studies on low-pH shot crete for rock sup port were based on available recipes of low-pH concrete mixtures for use in a repository. Pilot and full scale tests were carried out in Sweden and in Switzerland. (Author) 5 refs.

  1. 21 CFR 189.301 - Tin-coated lead foil capsules for wine bottles.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Tin-coated lead foil capsules for wine bottles. 189... lead foil capsules for wine bottles. (a) Tin-coated lead foil is composed of a lead foil coated on one... covering applied over the cork and neck areas) on wine bottles to prevent insect infestation, as a barrier...

  2. 75 FR 1596 - Grant of Authority for Subzone Status, Reynolds Packaging LLC (Aluminum Foil Liner Stock...

    Science.gov (United States)

    2010-01-12

    ... Status, Reynolds Packaging LLC (Aluminum Foil Liner Stock), Louisville, Kentucky Pursuant to its...-purpose subzone at the aluminum foil liner stock manufacturing and distribution facilities of Reynolds... manufacturing and distribution of aluminum foil liner stock and aluminum foil at the facilities of Reynolds...

  3. Finite Element Modelling of Bends and Creases during Folding Ultra Thin Stainless Steel Foils

    NARCIS (Netherlands)

    Datta, K.; Akagi, H.; Geijselaers, Hubertus J.M.; Huetink, Han

    2003-01-01

    Finite Element Modelling of an ultra thin foil of SUS 304 stainless steel is carried out. These foils are 20 mm and below in thickness. The development of stresses and strains during folding of these foils is studied. The objective of this study is to induce qualities of paper in the foils of

  4. Experimentqal and analytical study on thermocracking of alumina ceramic ring in a mechanical seal

    Science.gov (United States)

    Komiya, M.; Matsuda, K.; Kaneta, M.

    1994-04-01

    A mechanism of thermocracking, which occurs in an alumina ceramic ring of a mechanical face seal, is proposed based on experimental and analytical results. Methods for its prevention are also discussed. The experiments were conducted using an external type mechanical face seal composed of a carbon ring and three kinds of alumina ceramic rings, with distilled water as the liquid to be sealed. By using a layer of gold vacuum deposited onto the surface of the ceramic ring as a part of a DC circuit, the moment of crack initiation was identified. The thermal stresses produced in the ceramic ring by frictional heating were calculated using finite element analysis.

  5. Controlled electropolishing of copper foils at elevated temperature

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Gi Duk; Kim, Young Woo; Moyen, Eric; Keum, Dong Hoon [Department of Energy Science, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Lee, Young Hee [Department of Energy Science, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); IBS Center for Integrated Nanostructure Physics (CINAP), Institute of Basic Science (IBS), Daejeon (Korea, Republic of); Department of Physics, Sungkyunkwan Advanced Institute of Nano-technology (SAINT), Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Baik, Seunghyun [Department of Energy Science, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); School of Mechanical Engineering, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); IBS Center for Integrated Nanostructure Physics (CINAP), Institute of Basic Science (IBS), Daejeon (Korea, Republic of); Pribat, Didier, E-mail: didier53@skku.edu [Department of Energy Science, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of)

    2014-07-01

    We have studied the electrochemical polishing of copper foils at elevated temperature, in H{sub 3}PO{sub 4} electrolytes of various concentrations. Atomic force microscopy, surface reflectance measurements as well as optical microscopy and scanning electron microscopy (including electron backscattering diffraction) have been used throughout this study to characterize the surface of the electropolished foils. We have found that copper foils electropolished at 65 °C in 2.17 M H{sub 3}PO{sub 4}, exhibited a lower surface roughness and a higher percent specular reflection, comparing with values obtained after classical electropolishing in concentrated H{sub 3}PO{sub 4} at room temperature or comparing with values obtained after chemical-mechanical polishing. This work could open up new prospects for the preparation of copper foils before the growth of high quality graphene layers.

  6. A study of molecular effects in beam-foil spectroscopy

    International Nuclear Information System (INIS)

    Andresen, B.; Veje, E.

    1979-01-01

    Relative populations of ns + nd levels in hydrogen as functions of the principal quantum number n have been measured with beams of H + , H 2 + , and H 3 + impinging on thin carbon foils at 25 keV/amu and 100 keV/amu. Enhancements of 20% and 45% for dimer and trimer clusters are observed uniformly for all levels. A possible explanation in terms of screening of the Coulomb repulsion between the protons inside the foil, thus reducing the effective thickness of the foil, is given. All relative populations closely follow an nsup(P) power law with p = -4.0 and -3.7 at 25 keV/amu and 100 keV/amu, respectively, in perfect analogy with atomic collision experiments. O + /O 2 + -foil excitations at 100 keV and 155 keV show a simular molecular effect, but in reverse with a larger mean charge produced by the dimer. (Auth.)

  7. A procedure for rapid evaluation of carbon stripper foils

    International Nuclear Information System (INIS)

    Auble, R.L.; Galbraith, D.M.

    1982-01-01

    Lifetime measurements on carbon foils can become prohibitively time consuming and expensive with conventional particle accelerator beams. Therefore, a method has been developed which utilizes a beam of low energy (20 keV) nitrogen ions which allows tests to be conducted on relatively inexpensive equipment at very high damage rates. The beam is obtained from a General Ionex Model 1080 Sputterbell. Beam currents of the order of 1 μA cm -2 lead to failure of glow-discharge type foils on a time scale of, typically, 5-10 min. Lifetime ratios for glow-discharge versus evaporated foils obtained with this technique are in good agreement with those obtained with higher energy beams. Relative lifetimes for high energy and low energy bombardments are also found to be in good agreement with those predicted by damage energy calculations. The technique is currently being applied to the testing of glow discharge foils made with different feed gases and discharge conditions. (orig.)

  8. Decontamination with pasty pickling agents forming a strippable foil

    International Nuclear Information System (INIS)

    Weichselgartner, H.

    1991-01-01

    This paper describes the development of an in-situ decontamination procedure by applying onto the contaminated surface (in an one-step or multi-step process) pasty, chemically aggressive agents causing dilution and adsorption of the contaminant and then hardening to form a strippable foil. The use of such a foil will result in following advantages, with respect to usual techniques: - sensibly shorter operation duration resulting in lower personnel doses; - reduction of the arising secondary waste volume because there is no need for washing; the volume of the spent strippable foil is much smaller than currently used water volumes; - optimal conditioning of the radioactive waste due to its fixation in a solid (foil); - an accidental contamination in a controlled area can easily be fixed and covered avoiding its propagation

  9. Sealing of rock fractures

    International Nuclear Information System (INIS)

    Pusch, R.; Erlstroem, M.; Boergesson, L.

    1985-12-01

    The major water-bearing fractures in granite usually from fairly regular sets but the extension and degree of connectivity is varying. This means that only a few fractures that are interconnected with the deposition holes and larger water-bearing structures in a HLW repository are expected and if they can be identified and cut off through sealing it would be possible to improve the isolation of waste packages very effectively. Nature's own fracture sealing mechanisms may be simulated and a survey of the involved processes actually suggests a number of possible filling methods and substances. Most of them require high temperature and pressure and correspondingly sophisticated techniques, but some are of potential interest for immediate application with rather moderate effort. Such a technique is to fill the fractures with clayey substances which stay flexible and low-permeable provided that they remain physically and chemically intact. It is demonstrated in the report that effective grouting requires a very low viscosity and shear strength of the substance and this can be achieved by mechanical agitation as demonstrated in this report. Thus, by superimposing static pressure and shear waves induced by percussion hammering at a suitable frequency, clays and fine-grained silts as well as cement can be driven into fractures with an average aperture as small as 0.1 mm. Experiments were made in the laboratory using concrete and steel plates, and a field pilot test was also conducted under realistic conditions on site in Stripa. They all demonstrated the practicality of the 'dynamic injection technique' and that the fluid condition of the grouts yielded complete filling of the injected space to a considerable distance from the injection point. The field test indicated a good sealing ability as well as a surprisingly high resistance to erosion and piping. (author)

  10. Practical and research aspects of beam-foil spectroscopy

    International Nuclear Information System (INIS)

    Bashkin, S.

    1975-01-01

    The application of a heavy-ion accelerator to research in beam-foil spectroscopy requires certain capital equipment which is somewhat unorthodox when viewed from the standpoint of conventional, low-energy nuclear physics. It is necessary that people who wish to expand their accelerator work to include beam-foil studies understand the nature and cost of such major apparatus. We will survey the equipment needs, starting with the particle analyzer at the output of the accelerator and including the equipment used in a variety of beam-foil experiments. Electronic and computer devices will not be discussed since they are essentially identical with those employed in nuclear studies. Considerable attention will be given to optical spectrometers and spectographs including simple instruments which might be used by a laboratory just getting started in beam-foil research, or which has limited financial resources. Attention will be given to the production and use of the exciter foils. We will then discuss some typical beam-foil experiments having to do with the excitation, detection, and analysis of spectral lines from electronic levels in multiply-ionized atoms, and also with the measurement of the mean lives of such levels. Finally, we will review some of the special properties of the beam-foil light source as regards the population of the magnetic sub-states of a given level. Recent work on the character of the emitted light will be presented. That work will deal specifically with the origin of the polarization of the light. The relevant experiments involve varying the angle between the plane of the exciter foil and the particle velocity. (author)

  11. Alignment and orientation effects in beam-foil experiments

    International Nuclear Information System (INIS)

    Band, Y.B.

    1975-01-01

    A theory of the orientation and alignment of atoms observed upon emergence from tilted foils is presented. The interaction with the foil surface is taken into account in the production process of particular states. Once they are produced, the evolution of these states, under the influence of the residual field near the surface, is calculated in the fashion introduced by Eck. The most general effect of this evolution is presented

  12. Electrospray ionization with aluminum foil: A versatile mass spectrometric technique.

    Science.gov (United States)

    Hu, Bin; So, Pui-Kin; Yao, Zhong-Ping

    2014-03-19

    In this study, we developed a novel electrospray ionization (ESI) technique based on household aluminum foil (Al foil) and demonstated the desirable features and applications of this technique. Al foil can be readily cut and folded into desired configuration for effective ionization and for holding sample solution in bulk to allowing acquisition of durable ion signals. The present technique was demonstrated to be applicable in analysis of a wide variety of samples, ranging from pure chemical and biological compounds, e.g., organic compounds and proteins, to complex samples in liquid, semi-solid, and solid states, e.g., beverages, skincare cream, and herbal medicines. The inert, hydrophobic and impermeable surface of Al foil allows convenient and effective on-target extraction of solid samples and on-target sample clean-up, i.e., removal of salts and detergents from proteins and peptides, extending ESI device from usually only for sample loading and ionization to including sample processing. Moreover, Al foil is an excellent heat-conductor and highly heat-tolerant, permitting direct monitoring of thermal reactions, e.g., thermal denaturation of proteins. Overall, the present study showed that Al-foil ESI could be an economical and versatile method that allows a wide range of applications. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. Turbocharger with variable nozzle having vane sealing surfaces

    Science.gov (United States)

    Arnold, Philippe [Hennecourt, FR; Petitjean, Dominique [Julienrupt, FR; Ruquart, Anthony [Thaon les Vosges, FR; Dupont, Guillaume [Thaon les Vosges, FR; Jeckel, Denis [Thaon les Vosges, FR

    2011-11-15

    A variable nozzle for a turbocharger includes a plurality of vanes rotatably mounted on a nozzle ring and disposed in a nozzle flow path defined between the nozzle ring and an opposite nozzle wall. Either or both of the faces of the nozzle ring and nozzle wall include(s) at least one step that defines sealing surfaces positioned to be substantially abutted by airfoil surfaces of the vanes in the closed position of the vanes and to be spaced from the airfoil surfaces in positions other than the closed position. This substantial abutment between the airfoil surfaces and the sealing surfaces serves to substantially prevent exhaust gas from leaking past the ends of the airfoil portions. At the same time, clearances between the nozzle ring face and the end faces of the airfoil portions can be sufficiently large to prevent binding of the vanes under all operating conditions.

  14. About Face

    Medline Plus

    Full Text Available ... Type Search All Videos PTSD Basics PTSD Treatment What is AboutFace? Resources for Professionals Get Help Home ... All Videos Learn More PTSD Basics PTSD Treatment What is AboutFace? Resources for Professionals Get Help PTSD ...

  15. Non Destructive Seal Testing Polymeric Tray

    National Research Council Canada - National Science Library

    Bruins, Henderikus B

    2006-01-01

    .... The ND tester is based on a static compression force that reduces the volume of the tray and creates an internal pressure inside the tray and exposes the seal to forces that open the seal if the seal...

  16. Performance of Simple Gas Foil Thrust Bearings in Air

    Science.gov (United States)

    Bruckner, Robert J.

    2012-01-01

    Foil bearings are self-acting hydrodynamics devices used to support high speed rotating machinery. The advantages that they offer to process fluid lubricated machines include: high rotational speed capability, no auxiliary lubrication system, non-contacting high speed operation, and improved damping as compared to rigid hydrodynamic bearings. NASA has had a sporadic research program in this technology for almost 6 decades. Advances in the technology and understanding of foil journal bearings have enabled several new commercial products in recent years. These products include oil-free turbochargers for both heavy trucks and automobiles, high speed electric motors, microturbines for distributed power generation, and turbojet engines. However, the foil thrust bearing has not received a complimentary level of research and therefore has become the weak link of oil-free turbomachinery. In an effort to both provide machine designers with basic performance parameters and to elucidate the underlying physics of foil thrust bearings, NASA Glenn Research Center has completed an effort to experimentally measure the performance of simple gas foil thrust bearing in air. The database includes simple bump foil supported thrust bearings with full geometry and manufacturing techniques available to the user. Test conditions consist of air at ambient pressure and temperatures up to 500 C and rotational speeds to 55,000 rpm. A complete set of axial load, frictional torque, and rotational speed is presented for two different compliant sub-structures and inter-pad gaps. Data obtained from commercially available foil thrust bearings both with and without active cooling is presented for comparison. A significant observation made possible by this data set is the speed-load capacity characteristic of foil thrust bearings. Whereas for the foil journal bearing the load capacity increases linearly with rotational speed, the foil thrust bearing operates in the hydrodynamic high speed limit. In

  17. Repository Closure and Sealing Approach

    International Nuclear Information System (INIS)

    A.T. Watkins

    2000-01-01

    The scope of this analysis will be to develop the conceptual design of the closure seals and their locations in the Subsurface Facilities. The design will be based on the recently established program requirements for transitioning to the Site Recommendation (SR) design as outlined by ''Approach to Implementing the Site Recommendation Baseline'' (Stroupe 2000) and the ''Monitored Geologic Repository Project Description Document'' (CRWMS M andO 1999b). The objective of this analysis will be to assist in providing a description for the Subsurface Facilities System Description Document, Section 2 and finally to document any conclusions reached in order to contribute and provide support to the SR. This analysis is at a conceptual level and is considered adequate to support the SR design. The final closure barriers and seals for the ventilation shafts, and the north and south ramps will require these openings to be permanently sealed to limit excessive air and water inflows and prevent human intrusion. The major tasks identified with closure in this analysis are: (1) Developing the overall subsurface seal layout and identifying design and operational interfaces for the Subsurface Facilities. (2) Summarizing the general site conditions and general rock characteristic with respect to seal location and describing the seal selected. (3) Identify seal construction materials, methodology of construction and strategic locations including design of the seal and plugs. (4) Discussing methods to prevent human intrusion

  18. Cryogenic Pressure Seal for Wires

    Science.gov (United States)

    Ciana, J. J.

    1984-01-01

    High-pressure-seal formed by forcing polyurethane into space surrounding wire or cable in special fitting. Wire or cable routed through fitting then through a tightly fitting cap. Wire insulation left intact. Cap filled with sealant and forced onto the fitting: this pushes sealant into fitting so it seals wire or cable in fitting as well as in cap.

  19. Rotating plug bearing and seal

    International Nuclear Information System (INIS)

    Wade, E.E.

    1977-01-01

    Disclosed is a bearing and seal structure for nuclear reactors utilizing rotating plugs above the nuclear reactor vessel. The structure permits lubrication of bearings and seals of the rotating plugs without risk of the lubricant draining into the reactor vessel below. The structure permits lubrication by utilizing a rotating outer race bearing. 19 claims, 3 figures

  20. Seals. Grades 3-6.

    Science.gov (United States)

    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…

  1. Development and preparation of thin, supported targets and stripper foils

    International Nuclear Information System (INIS)

    Aaron, W.S.; Petek, M.; Zevenbergen, L.A.; Gibson, J.R.

    1989-01-01

    Usually, it is desirable to prepare thin films that are self-supporting so that any extraneous support materials will not interfere with experimental measurements. However, films with very low areal densities, films other than metals or films covering large areas may require the use of a backing or support. Two classes of supported thin films are being developed by the Isotope Research Materials Laboratory (IRML). Electrodeposition of oxide thin films is a fairly common target preparation technique that is usually performed on backings such as thin metal foils or low atomic number materials like Be and to a lesser extent, C foils. Techniques have been developed by IRML that result in electrodeposition of oxide films up to 500 μg/cm 2 on carbon foils or aluminized mylar. Electrodeposition is a very attractive target fabrication method since it is very efficient in the usage of rare and/or valuable isotopes. The ability to prepare these films on carbon or mylar foils provides a target that has, in most applications, far less interference resulting from the backing. Thin films of carbon, aluminum, boron and titanium are being used as stripper foils in the generation of neutral (H - →H 0 ) particle beams with energies of 50 MeV or greater. Neutralizer foils as large as 25 cm x 25 cm have been prepared from Al and C in thicknesses ranging from 5 to 12 μg/cm 2 that are mounted on thin nickel grids with a transmittance of approximately 90%. Significantly larger foils are currently under development. (orig.)

  2. Interaction of relativistic H- ions with thin foils

    International Nuclear Information System (INIS)

    Mohagheghi, A.H.

    1990-09-01

    The response of relativistic H - ions to thin carbon foils was investigated for beam energies ranging from 226 MeV to 800 MeV. For the foil thicknesses we have studied, ranging from 15 to 300 μg/cm 2 , an appreciable fraction of the H - beam survives intact, some H - ions are stripped down to protons, and the remainder is distributed over the states of H 0 . This experiment is different from the low energy studies in that the projectile velocity is comparable to the speed of light, leading to an interaction time of typically less than a femtosecond. The present results challenge the theoretical understanding of the interaction mechanisms. An electron spectrometer was used to selectively field-ionize the Rydberg states, 9 < n < 17, at beam energies of 581 MeV and 800 MeV. The yield of low-lying states were measured by Doppler tuning a Nd:YAG laser to excite transitions to a Rydberg state which was then field-ionized and detected. A simple model is developed to fit the yield of each state as a function of foil thickness. The simple model is successful in predicting the general features of the yield data. However, the data are suggestive of a more complex structure in the yield curves. The yield of a given state depends strongly on the foil thickness, demonstrating that the excited states are formed during the passage of the ions through a foil. The optimum thickness to produce a given state increases with the principal quantum number of the state suggesting an excitation process which is at least pratially stepwise. The results of a Monte Carlo simulation are compared with the experimental data to estimate the distribution of the excited states coming out of a foil. The distributions of the excited states and their dependence on foil thickness are discussed

  3. Turbine and Structural Seals Team Facilities

    Data.gov (United States)

    Federal Laboratory Consortium — Seals Team Facilities conceive, develop, and test advanced turbine seal concepts to increase efficiency and durability of turbine engines. Current projects include...

  4. The use of foils in the construction industry for the correction of the thermal behavior of roofing systems: an experimental evaluation

    Directory of Open Access Journals (Sweden)

    Francisco Vecchia

    2005-02-01

    Full Text Available This article deals with a field experiment, having tested foils as a measure of environmental correction of the thermal behavior of an inhabited construction. Considering the inexistence of suitable models that simulate quantitatively the effect of thermal isolation caused by light-coloured metal foils, in a thermal-barrier form, it was chosen to develop and use a measurement automatic empirical system, by means of the use of type T thermopairs and datalogger CR10X, Campbell Scientific. It was then registered and verified the fluctuations of the surface and air temperatures, registered inside the above mentioned inhabited construction, before and after the installation of double-faced bright foils, structured to resist mechanical strengths, as a way of reducing the thermal flow by the covering system: wood ceiling, Pinus elliottis, foils and ceramic tiles. Furthermore, it was used the climatic rythm concept for the choice of two measurement periods, in summer episodes, as well as of the typical days which represent this study, before and after the placing of foils.

  5. Reading faces and Facing words

    DEFF Research Database (Denmark)

    Robotham, Julia Emma; Lindegaard, Martin Weis; Delfi, Tzvetelina Shentova

    perception of faces and words is affected by unilateral posterior stroke. Two patients with lesions in their dominant hemisphere and two with lesions in their non-dominant hemisphere were tested on sensitive tests of face and word perception during the stable phase of recovery. Despite all patients having...... unilateral lesions, we found no patient with a selective deficit in either reading or face processing. Rather, the patients showing a deficit in processing either words or faces were also impaired with the other category. One patient performed within the normal range on all tasks. In addition, all patients...... performed within normal range on at least one test of visual categorisation, strongly suggesting that their abnormal performance with words and faces does not represent a generalised visuo-perceptual deficit. Our results suggest that posterior areas in both hemispheres may be critical for both reading...

  6. Tamper tape seals

    International Nuclear Information System (INIS)

    Wright, B.W.; Undem, H.A.

    1994-07-01

    Tamper tapes are appealing for many applications due to their ease of use and relative robustness. Applications include seals for temporary area denial, protection of sensitive equipment, chain-of-custody audit trails, and inventory control practices. A next generation of adhesive tamper tapes is being developed that combines the best features of commercially available devices with additional state-of-the-art features in tamper indication, tamper-resistance, and counterfeit-resistance. The additional features are based on U.S. Department of Energy (DOE) research and development (R ampersand D) activities that were originally associated with preparations for the Strategic Arms Reduction Treaty (START). New features include rapid-set, chemical-cure adhesive systems that allow user-friendly application and layered levels of counterfeit-resistance based on unique open-quotes fingerprintclose quotes characteristics that can be accessed as desired

  7. High pressure mechanical seal

    Science.gov (United States)

    Babel, Henry W. (Inventor); Anderson, Raymond H. (Inventor)

    1996-01-01

    A relatively impervious mechanical seal is formed between the outer surface of a tube and the inside surface of a mechanical fitting of a high pressure fluid or hydraulic system by applying a very thin soft metal layer onto the outer surface of the hard metal tube and/or inner surface of the hard metal fitting. The thickness of such thin metal layer is independent of the size of the tube and/or fittings. Many metals and alloys of those metals exhibit the requisite softness, including silver, gold, tin, platinum, indium, rhodium and cadmium. Suitably, the coating is about 0.0025 millimeters (0.10 mils) in thickness. After compression, the tube and fitting combination exhibits very low leak rates on the order or 10.sup.-8 cubic centimeters per second or less as measured using the Helium leak test.

  8. Dosimetric response of united, commercially available CTA foils for sup 6 sup 0 Co gamma rays

    CERN Document Server

    Peimel-Stuglik, Z

    2001-01-01

    The usefulness of two kinds of untinted CTA foils: Fuji CTR-125 dosimetric foil and technical CTA-T foil, produced by 'Zaklady Chemiczne, 'Gorzow Wielkopolski' as support for light-sensitive layers of amateur photo-films, for sup 6 sup 0 Co gamma ray dosimetry was investigated. In spite of rather bad physical parameters of the technical foil (spread of foil thickness, high and different initial absorbance) the dosimetric response of both foils for sup 6 sup 0 Co gamma rays was similar. The CTA-T foil can be used for routine dosimetry providing that dosimetric signals have to be calculated exactly as recommended by the ASTM (American Society for Testing and Materials) standard, i.e. as the difference of absorbance of irradiated and (the same) non-irradiated foil. Any other approach may lead to high errors of dose evaluation. The last is true also for other CTA foils, especially after long self-life.

  9. About Face

    Medline Plus

    Full Text Available ... by Topic Videos by Type Search All Videos Learn More PTSD Basics PTSD Treatment What is AboutFace? ... types of therapy that are proven to work. Learn more about Prolonged Exposure (PE) and Cognitive Processing ...

  10. About Face

    Medline Plus

    Full Text Available Skip to Content Menu Closed (Tap to Open) Home Videos by Topic Videos by Type Search All ... What is AboutFace? Resources for Professionals Get Help Home Watch Videos by Topic Videos by Type Search ...

  11. The feed-out process: Rayleigh-Taylor and Richtmyer-Meshkov instabilities in thin, laser-driven foils

    Energy Technology Data Exchange (ETDEWEB)

    Smitherman, D.P.

    1998-04-01

    Eight beams carrying a shaped pulse from the NOVA laser were focused into a hohlraum with a total energy of about 25 kJ. A planar foil was placed on the side of the hohlraum with perturbations facing away from the hohlraum. All perturbations were 4 {micro}m in amplitude and 50 {micro}m in wavelength. Three foils of pure aluminum were shot with thicknesses and pulse lengths respectively of 86 {micro}m and 2. 2 ns, 50 {micro}m and 4.5 ns, and 35 {micro}m with both 2.2 ns and 4. 5 ns pulses. Two composite foils constructed respectively of 32 and 84 {micro}m aluminum on the ablative side and 10 {micro}m beryllium on the cold surface were also shot using the 2.2 ns pulse. X-ray framing cameras recorded perturbation growth using both face- and side-on radiography. The LASNEX code was used to model the experiments. A shock wave interacted with the perturbation on the cold surface generating growth from a Richtmyer-Meshkov instability and a strong acoustic mode. The cold surface perturbation fed-out to the Rayleigh-Taylor unstable ablation surface, both by differential acceleration and interface coupling, where it grew. A density jump did not appear to have a large effect on feed-out from interface coupling. The Rayleigh-Taylor instability`s vortex pairs overtook and reversed the direction of flow of the Richtmyer-Meshkov vortices, resulting in the foil moving from a sinuous to a bubble and spike configuration. The Rayleigh-Taylor instability may have acted as an ablative instability on the hot surface, and as a classical instability on the cold surface, on which grew second and third order harmonics.

  12. An Experimental Study on Micro Clinching of Metal Foils with Cutting by Laser Shock Forming.

    Science.gov (United States)

    Wang, Xiao; Li, Cong; Ma, Youjuan; Shen, Zongbao; Sun, Xianqing; Sha, Chaofei; Gao, Shuai; Li, Liyin; Liu, Huixia

    2016-07-13

    This paper describes a novel technique for joining similar and dissimilar metal foils, namely micro clinching with cutting by laser shock forming. A series of experiments were conducted to study the deformation behavior of single layer material, during which many important process parameters were determined. The process window of the 1060 pure aluminum foils and annealed copper foils produced by micro clinching with cutting was analyzed. Moreover, similar material combination (annealed copper foils) and dissimilar material combination (1060 pure aluminum foils and 304 stainless steel foils) were successfully achieved. The effect of laser energy on the interlock and minimum thickness of upper foils was investigated. In addition, the mechanical strength of different material combinations joined by micro clinching with cutting was measured in single lap shearing tests. According to the achieved results, this novel technique is more suitable for material combinations where the upper foil is thicker than lower foil. With the increase of laser energy, the interlock increased while the minimum thickness of upper foil decreased gradually. The shear strength of 1060 pure aluminum foils and 304 stainless steel foils combination was three times as large as that of 1060 pure aluminum foils and annealed copper foils combination.

  13. An Experimental Study on Micro Clinching of Metal Foils with Cutting by Laser Shock Forming

    Directory of Open Access Journals (Sweden)

    Xiao Wang

    2016-07-01

    Full Text Available This paper describes a novel technique for joining similar and dissimilar metal foils, namely micro clinching with cutting by laser shock forming. A series of experiments were conducted to study the deformation behavior of single layer material, during which many important process parameters were determined. The process window of the 1060 pure aluminum foils and annealed copper foils produced by micro clinching with cutting was analyzed. Moreover, similar material combination (annealed copper foils and dissimilar material combination (1060 pure aluminum foils and 304 stainless steel foils were successfully achieved. The effect of laser energy on the interlock and minimum thickness of upper foils was investigated. In addition, the mechanical strength of different material combinations joined by micro clinching with cutting was measured in single lap shearing tests. According to the achieved results, this novel technique is more suitable for material combinations where the upper foil is thicker than lower foil. With the increase of laser energy, the interlock increased while the minimum thickness of upper foil decreased gradually. The shear strength of 1060 pure aluminum foils and 304 stainless steel foils combination was three times as large as that of 1060 pure aluminum foils and annealed copper foils combination.

  14. Smooth nylon foil (SupraFOIL) orbital implants in orbital fractures: a case series of 181 patients.

    Science.gov (United States)

    Park, D J John; Garibaldi, Daniel C; Iliff, Nicholas T; Grant, Michael P; Merbs, Shannath L

    2008-01-01

    The SupraFOIL smooth nylon foil implant is a polyamide sheet available in varying thicknesses that has been used in orbital reconstruction following trauma. The authors report their experience with smooth nylon foil implants in the repair of orbital fractures. A retrospective chart review of patients having undergone repair of orbital fractures between January 1, 1995 and December 31, 2003 was conducted. The Wilcoxon test was used to compare cases with complications and those with no complications. Of 282 orbits that underwent fracture repair with alloplastic material, 87 were excluded because non-nylon foil implants were used alone or in combination with nylon foil to repair the orbital fracture. An additional 14 fractures were excluded because of insufficient clinical data or lack of follow-up, for a total of 181 orbits that underwent orbital fracture repair with only nylon foil. A transconjunctival approach was used in 98% cases, and all 181 implants were fixated with at least 1 titanium screw. Average follow-up was 362.8 days. The overall complication rate was 1.7%. One patient had an acute postoperative orbital hemorrhage (0.6% acute complication rate). Two patients had late orbital infections, 683 days and 984 days following repair (1.1% late complication rate). The authors found the smooth nylon foil implant to be safe and effective in orbital fracture repair. The lower rate of complications the authors observed compared with previously reported series may be related to implant fixation. A titanium screw secured just posterior to the orbital rim may decrease long-term complications by providing more stability than implants left without fixation.

  15. Dynamics and locomotion of flexible foils in a frictional environment

    Science.gov (United States)

    Wang, Xiaolin; Alben, Silas

    2018-01-01

    Over the past few decades, oscillating flexible foils have been used to study the physics of organismal propulsion in different fluid environments. Here, we extend this work to a study of flexible foils in a frictional environment. When the foil is oscillated by heaving at one end but is not free to locomote, the dynamics change from periodic to non-periodic and chaotic as the heaving amplitude increases or the bending rigidity decreases. For friction coefficients lying in a certain range, the transition passes through a sequence of N-periodic and asymmetric states before reaching chaotic dynamics. Resonant peaks are damped and shifted by friction and large heaving amplitudes, leading to bistable states. When the foil is free to locomote, the horizontal motion smoothes the resonant behaviours. For moderate frictional coefficients, steady but slow locomotion is obtained. For large transverse friction and small tangential friction corresponding to wheeled snake robots, faster locomotion is obtained. Travelling wave motions arise spontaneously, and move with horizontal speeds that scale as transverse friction coefficient to the power 1/4 and input power that scales as the transverse friction coefficient to the power 5/12. These scalings are consistent with a boundary layer form of the solutions near the foil's leading edge.

  16. Electronically Controlled Mechanical Seal for Aerospace Applications -- Part 1: Design, Analysis, and Steady State Tests

    Science.gov (United States)

    Salant, Richard F.; Wolff, Paul; Navon, Samuel

    1994-01-01

    An electronically-controlled mechanial seal, for use as the purge gas seal in a liquid oxygen turbopump, has been designed, analyzed, and built. The thickness of the lubricating film between the faces is controlled by adjusting the coning of the carbon face. This is done by applying a voltage across a piezoelectric element to which the carbon face is bound. Steady state tests have shown that the leakage rate (and film thickness) can be adjusted over a substantial range, utilizing the available range of voltage.

  17. Electronically controled mechanical seal for aerospace applications -- Part 1: Design, analysis, and steady state tests

    Science.gov (United States)

    Salant, Richard F.; Wolff, Paul; Navon, Samuel

    1994-01-01

    An electronically-controlled mechanial seal, for use as the purge gas seal in a liquid oxygen turbopump, has been designed, analyzed, and built. The thickness of the lubricating film between the faces is controlled by adjusting the coning of the carbon face. This is done by applying a voltage across a piezoelectric element to which the carbon face is bound. Steady state tests have shown that the leakage rate (and film thickness) can be adjusted over a substantial range, utilizing the available range of voltage.

  18. Leak detection of KNI seals

    International Nuclear Information System (INIS)

    Baranyai, G.; Peter, A.; Windberg, P.

    1990-03-01

    In Unit 3 and 4 of the Paks Nuclear Power Plant, Hungary, KNI type seals are used as lead-throughs with conical nickel sealing rings. Their failure can be critical for the operation of the reactor. An Acoustical Leak Detection System (ALDS) was constructed and tested for the operational testing of the seals. Some individual papers are presented in this collection on the calibration and testing of the ALDS intended to be placed on the top of the reactor vessels. The papers include simulation measurements of Unit 3 of NPP, laboratory experiments, evaluation of measurements, and further development needs with the ALDS. (R.P.) 50 figs.; 19 tabs

  19. Study of graphite sealing for the instrumentation feed through part

    International Nuclear Information System (INIS)

    Hong, Jintae; Ahn, Sungho; Joung, Changyoung; Kim, Kahye

    2013-01-01

    Because highly pressurized (15.5 MPa) and highly heated (300 .deg. C) coolant is circulated through the test rig, it needs to seal out the instrumentation feed through part. In this case, general sealing method is brazing and several works have been carried out in nuclear fields. However, because high temperature is induced on the sealing plug and sheaths, it is easy to be broken due to oxidisation of the sheath during brazing process. In addition, because the brazing process is irreversible, if the brazing process fails, the whole inner assembly should be scrapped out. Another approach which uses graphite has been studied to seal out the instrumentation feed through part. In the study, graphite sealing is considered as a sealing method and the improvement of mechanical structure has been studied to improve the workability. To check the sealing performance of the instrumentation feed through part, a hydraulic pressure test and a helium leak test were carried out according to the ASME section III. The criterion of a hydraulic pressure test is 125% of the design pressure. In this study, because the design pressure of the pressure vessel is 17.5 MPa. the sealing criterion should be 21.9 MPa. Also, in a Helium leak test, the criterion is less than 5 Χ 10 -9 torr·liter/sec. At first, a Helium leak test was carried out. After eliminating Helium in the pressure vessel by evacuating the internal area of the pressure vessel up to 1 Χ 10 -3 torr using ASM 310, Helium detection test was carried out by spraying Helium gas at the top face of the top flange for 5 minutes. Fig. 4 shows the rate of Helium leakage is 2.4 Χ 10 -9 torr·liter/sec, and it satisfies the sealing performance criterion. A hydraulic pressure test was also carried out, and there was no leakage or pressure drop when the water in the pressure vessel is pressurized up to 22.5 MPa. The above test results show that graphite powder can seal out the instrumentation feed through part easily with the improved

  20. Reusable tamper-indicating security seal. [Patent Application

    Energy Technology Data Exchange (ETDEWEB)

    Ryan, M.J.

    1981-06-23

    The invention teaches means for detecting unauthorized tampering or substitutions of a device, and has particular utility when applied on a seal device used to secure a location or thing. The seal has a transparent body wall, and a first indicia, viz., a label identification is formed on the inside surface of this wall. Second and third indicia are formed on the outside surface of the transparent wall, and each of these indicia is transparent to allow the parallax angled viewing of the first indicia through these indicia. The second indicia is in the form of a broadly uniform pattern, viz., many small spaced dots; while the third indicia is in the form of easily memorized objects, such as human faces, made on a substrate by means of halftone printing. The substrate is lapped over the outside surface of the transparent wall. A thin cocoon of a transparent material, generally of the same material as the substrate such as plastic, is formed over the seal body and specifically over the transparent wall and the second and third indicia formed thereon. This cocoon is seamless and has walls of nonuniform thickness. Both the genuineness of the seal and whether anyone has attempted to compromise the seal can thus be visually determined upon inspection.

  1. Foil Bearing Coating Behavior in CO2

    Energy Technology Data Exchange (ETDEWEB)

    Walker, Matthew [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Kruizenga, Alan Michael [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Pasch, James Jay [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Fleming, Darryn [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-08-01

    The Sandia S-CO2 Recompression Closed Brayton Cycle (RCBC) utilizes a series of gas foil bearings in its turbine-alternator-compressors. At high shaft rotational speed these bearings allow the shaft to ride on a cushion of air. Conversely, during startup and shutdown, the shaft rides along the foil bearing surface. Low-friction coatings are used on bearing surfaces in order to facilitate rotation during these periods. An experimental program was initiated to elucidate the behavior of coated bearing foils in the harsh environments of this system. A test configuration was developed enabling long duration exposure tests, followed by a range of analyses relevant to their performance in a bearing. This report provides a detailed overview of this work. The results contained herein provide valuable information in selecting appropriate coatings for more advanced future bearing-rig tests at the newly established test facility in Sandia-NM.

  2. Model-Based Optimization for Flapping Foil Actuation

    Science.gov (United States)

    Izraelevitz, Jacob; Triantafyllou, Michael

    2014-11-01

    Flapping foil actuation in nature, such as wings and flippers, often consist of highly complex joint kinematics which present an impossibly large parameter space for designing bioinspired mechanisms. Designers therefore often build a simplified model to limit the parameter space so an optimum motion trajectory can be experimentally found, or attempt to replicate exactly the joint geometry and kinematics of a suitable organism whose behavior is assumed to be optimal. We present a compromise: using a simple local fluids model to guide the design of optimized trajectories through a succession of experimental trials, even when the parameter space is too large to effectively search. As an example, we illustrate an optimization routine capable of designing asymmetric flapping trajectories for a large aspect-ratio pitching and heaving foil, with the added degree of freedom of allowing the foil to move parallel to flow. We then present PIV flow visualizations of the optimized trajectories.

  3. Compliant Foil Journal Bearings - Investigation of Dynamic Properties

    DEFF Research Database (Denmark)

    Larsen, Jon Steffen; Santos, Ilmar

    and dynamic coefficients, of the compliant foil bearing together with an efficient solution method, which can be easily adopted and implemented by mechanical engineers. A theoretical model of a radial compliant foil bearing that incorporates compressibility of the lubricating gas and flexibility...... a Bubnow-Galerkin approach. This constitutes the main original contribution of this work, considering the fact that the finite difference method is commonly used and thouroughly investigated in the literature. The finite element method leads to a set of non-linear equations for the static fluid film...... on the compliant foil bearings, and the understanding of their dynamic behaviour is growing. However, practical design involving these bearings are still associated with a large degree of trial and error. This study aims at establishing an accurate mathematical model, to calculate the pressure, film height...

  4. Acceleration of polyethelene foils by laser driven ablation

    International Nuclear Information System (INIS)

    Ahlstrom, H.G.; Burginyon, G.A.; Haas, R.A.

    1974-01-01

    The production of thermonuclear energy, by laser driven implosion of spherical DT shells, with achievable laser technology, requires the development of an efficient and stable implosion. Certain aspects of the acceleration of the spherical shells can be studied experimentally by irradiating thin, 5 to 25 μm, polyethelene foils. The results of foil acceleration experiments performed using a Nd:YAG-Glass laser capable of producing 150 J, 1 nsec pulses will be discussed. The dynamics of the accelerated foil, the ion blow off, high energy electron spectrum (6 to 180 keV), x-ray spectrum (1 to 150 keV) the spatial distribution of the x-ray emission, the laser beam focal spot energy distribution, the laser temporal pulse shape and spectrum for reflected and transmitted radiation have all been measured simultaneously. The results of these measurements are compared with detailed numerical simulations. (U.S.)

  5. 7 CFR 29.35 - Lot seal.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Lot seal. 29.35 Section 29.35 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... INSPECTION Regulations Definitions § 29.35 Lot seal. A seal approved by the Director for sealing lots of...

  6. 7 CFR 29.34 - Sample seal.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Sample seal. 29.34 Section 29.34 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... INSPECTION Regulations Definitions § 29.34 Sample seal. A seal approved by the Director for sealing official...

  7. Transmission of fast molecular ions through thin foils

    International Nuclear Information System (INIS)

    Pietsch, W.J.; Gemmell, D.S.; Cooney, P.J.; Kanter, E.P.; Kurath, D.; Ratkowski, A.J.; Vager, Z.; Zabransky, B.J.

    1979-01-01

    New results on the transmission of fast molecular ions through thin foils are presented and a mechanism for the transmission process is proposed. The main feature of the postulated mechanism is that a finite fraction of the incident molecular beam does not undergo a strong Coulomb explosion while traversing the foil. Because the emerging fragments are at large internuclear separations, there is an enhanced probability for the formation of bound, long-range, excited electronic states following electron capture at the rear surface of the target

  8. Method and apparatus for tensile testing of metal foil

    Science.gov (United States)

    Wade, O. W. (Inventor)

    1976-01-01

    A method for obtaining accurate and reproducible results in the tensile testing of metal foils in tensile testing machines is described. Before the test specimen are placed in the machine, foil side edges are worked until they are parallel and flaw free. The specimen are also aligned between and secured to grip end members. An aligning apparatus employed in the method is comprised of an alignment box with a longitudinal bottom wall and two upright side walls, first and second removable grip end members at each end of the box, and a means for securing the grip end members within the box.

  9. Electrochemically replicated smooth aluminum foils for anodic alumina nanochannel arrays

    International Nuclear Information System (INIS)

    Biring, Sajal; Tsai, K-T; Sur, Ujjal Kumar; Wang, Y-L

    2008-01-01

    A fast electrochemical replication technique has been developed to fabricate large-scale ultra-smooth aluminum foils by exploiting readily available large-scale smooth silicon wafers as the masters. Since the adhesion of aluminum on silicon depends on the time of surface pretreatment in water, it is possible to either detach the replicated aluminum from the silicon master without damaging the replicated aluminum and master or integrate the aluminum film to the silicon substrate. Replicated ultra-smooth aluminum foils are used for the growth of both self-organized and lithographically guided long-range ordered arrays of anodic alumina nanochannels without any polishing pretreatment

  10. Alaska Harbor Seal Glacial Surveys

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Floating glacial ice serves as a haul-out substrate for a significant number (10-15%) of Alaskan harbor seals, and thus surveying tidewater glacial fjords is an...

  11. Northern Fur Seal Food Habits

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains food habits samples, usually scats, collected opportunistically on northern fur seal rookeries and haulouts in Alaska from 1987 to present....

  12. M1 Abrams Seal Ring

    National Research Council Canada - National Science Library

    2004-01-01

    .... The 3.650-inch-diameter, 0.500-inch-wide seal, made of wrought A-286 nickel-iron super alloy, is difficult to clamp securely during machining, making it a challenge to maintain required roundness tolerances...

  13. Brush Seals for Improved Steam Turbine Performance

    Science.gov (United States)

    Turnquist, Norman; Chupp, Ray; Baily, Fred; Burnett, Mark; Rivas, Flor; Bowsher, Aaron; Crudgington, Peter

    2006-01-01

    GE Energy has retrofitted brush seals into more than 19 operating steam turbines. Brush seals offer superior leakage control compared to labyrinth seals, owing to their compliant nature and ability to maintain very tight clearances to the rotating shaft. Seal designs have been established for steam turbines ranging in size from 12 MW to over 1200 MW, including fossil, nuclear, combined-cycle and industrial applications. Steam turbines present unique design challenges that must be addressed to ensure that the potential performance benefits of brush seals are realized. Brush seals can have important effects on the overall turbine system that must be taken into account to assure reliable operation. Subscale rig tests are instrumental to understanding seal behavior under simulated steam-turbine operating conditions, prior to installing brush seals in the field. This presentation discusses the technical challenges of designing brush seals for steam turbines; subscale testing; performance benefits of brush seals; overall system effects; and field applications.

  14. Sealed can of spent fuel

    International Nuclear Information System (INIS)

    Suzuki, Yasuyuki.

    1976-01-01

    Object: To provide a seal plug cover with a gripping portion fitted to a canning machine and a gripping portion fitted to a gripper of the same configuration as a fuel body for handling the fuel body so as to facilitate the handling work. Structure: A sealed can comprises a vessel and a seal plug cover, said cover being substantially in the form of a bottomed cylinder, which is slipped on the vessel and air-tightly secured by a fastening bolt between it and a flange. The spent fuel body is received into the vessel together with coolant during the step of canning operation. Said seal plug cover has two gripping portions, one for opening and closing the plug cover of the canning machine as an exclusive use member, the other being in the form of a hook-shaped peripheral groove, whereby the gripping portions may be effectively used using the same gripper when the spent fuel body is transported while being received in the sealed can or when the fuel body is removed from the sealed can. (Kawakami, Y.)

  15. Reusable, tamper-indicating seal

    International Nuclear Information System (INIS)

    Ryan, M.J.

    1978-01-01

    A reusable, tamper-indicating seal is comprised of a drum confined within a fixed body and rotatable in one direction therewithin, the top of the drum constituting a tray carrying a large number of small balls of several different colors. The fixed body contains parallel holes for looping a seal wire therethrough. The base of the drums carries cams adapted to coact with cam followers to lock the wire within the seal at one angular position of the drum. A channel in the fixed body, visible from outside the seal, adjacent the tray constitutes a segregated location for a small plurality of the colored balls. A spring in the tray forces colored balls into the segregated location at one angular position of the drum, further rotation securing the balls in position and the wires in the seal. A wedge-shaped plough removes the balls from the segregated location, at a different angular position of the drum, the wire being unlocked at the same postion. A new pattern of colored balls will appear in the segregated location when the seal is relocked

  16. About Face

    Medline Plus

    Full Text Available ... What is AboutFace? Resources for Professionals Get Help PTSD We've been there. After a traumatic event — ... you're not feeling better, you may have PTSD (posttraumatic stress disorder). Watch the intro This is ...

  17. About Face

    Medline Plus

    Full Text Available ... to Content Menu Closed (Tap to Open) Home Videos by Topic Videos by Type Search All Videos PTSD Basics PTSD Treatment What is AboutFace? Resources for Professionals Get Help Home Watch Videos by Topic Videos by Type Search All Videos ...

  18. About Face

    Medline Plus

    Full Text Available ... at first. But if it's been months or years since the trauma and you're not feeling better, you may have PTSD (posttraumatic stress disorder). Watch the intro This is AboutFace In these videos, Veterans, family members, ...

  19. About Face

    Medline Plus

    Full Text Available ... traumatic event — like combat, an assault, or a disaster — it's normal to feel scared, keyed up, or sad at first. But if it's been months or years since the trauma and you're not feeling better, you may have PTSD (posttraumatic stress disorder). Watch the intro This is AboutFace In ...

  20. Hydrodynamic perception in true seals (Phocidae) and eared seals (Otariidae).

    Science.gov (United States)

    Hanke, Wolf; Wieskotten, Sven; Marshall, Christopher; Dehnhardt, Guido

    2013-06-01

    Pinnipeds, that is true seals (Phocidae), eared seals (Otariidae), and walruses (Odobenidae), possess highly developed vibrissal systems for mechanoreception. They can use their vibrissae to detect and discriminate objects by direct touch. At least in Phocidae and Otariidae, the vibrissae can also be used to detect and analyse water movements. Here, we review what is known about this ability, known as hydrodynamic perception, in pinnipeds. Hydrodynamic perception in pinnipeds developed convergently to the hydrodynamic perception with the lateral line system in fish and the sensory hairs in crustaceans. So far two species of pinnipeds, the harbour seal (Phoca vitulina) representing the Phocidae and the California sea lion (Zalophus californianus) representing the Otariidae, have been studied for their ability to detect local water movements (dipole stimuli) and to follow hydrodynamic trails, that is the water movements left behind by objects that have passed by at an earlier point in time. Both species are highly sensitive to dipole stimuli and can follow hydrodynamic trails accurately. In the individuals tested, California sea lions were clearly more sensitive to dipole stimuli than harbour seals, and harbour seals showed a superior trail following ability as compared to California sea lions. Harbour seals have also been shown to derive additional information from hydrodynamic trails, such as motion direction, size and shape of the object that caused the trail (California sea lions have not yet been tested). The peculiar undulated shape of the harbour seals' vibrissae appears to play a crucial role in trail following, as it suppresses self-generated noise while the animal is swimming.

  1. Performance of the carbon stripping foils in the Argonne FN tandem

    International Nuclear Information System (INIS)

    Den Hartog, P.K.; Munson, F.; Heath, C.; Thomas, G.

    1980-01-01

    Carbon stripping foils produced by the glow discharge cracking of ethylene were produced and the foils were tested in the Argonne FN tandem accelerator. The results are presented and the characteristics of stripping media are discussed

  2. Design, Fabrication and Performance of Open Source Generation I and II Compliant Hydrodynamic Gas Foil Bearings

    Science.gov (United States)

    DellaCorte, Christopher; Radil, Kevin C.; Bruckner, Robert J.; Howard, S. Adam

    2007-01-01

    Foil gas bearings are self-acting hydrodynamic bearings made from sheet metal foils comprised of at least two layers. The innermost top foil layer traps a gas pressure film that supports a load while a layer or layers underneath provide an elastic foundation. Foil bearings are used in many lightly loaded, high-speed turbo-machines such as compressors used for aircraft pressurization, and small micro-turbines. Foil gas bearings provide a means to eliminate the oil system leading to reduced weight and enhanced temperature capability. The general lack of familiarity of the foil bearing design and manufacturing process has hindered their widespread dissemination. This paper reviews the publicly available literature to demonstrate the design, fabrication and performance testing of both first and second generation bump style foil bearings. It is anticipated that this paper may serve as an effective starting point for new development activities employing foil bearing technology.

  3. A new modal-based approach for modelling the bump foil structure in the simultaneous solution of foil-air bearing rotor dynamic problems

    Science.gov (United States)

    Bin Hassan, M. F.; Bonello, P.

    2017-05-01

    Recently-proposed techniques for the simultaneous solution of foil-air bearing (FAB) rotor dynamic problems have been limited to a simple bump foil model in which the individual bumps were modelled as independent spring-damper (ISD) subsystems. The present paper addresses this limitation by introducing a modal model of the bump foil structure into the simultaneous solution scheme. The dynamics of the corrugated bump foil structure are first studied using the finite element (FE) technique. This study is experimentally validated using a purpose-made corrugated foil structure. Based on the findings of this study, it is proposed that the dynamics of the full foil structure, including bump interaction and foil inertia, can be represented by a modal model comprising a limited number of modes. This full foil structure modal model (FFSMM) is then adapted into the rotordynamic FAB problem solution scheme, instead of the ISD model. Preliminary results using the FFSMM under static and unbalance excitation conditions are proven to be reliable by comparison against the corresponding ISD foil model results and by cross-correlating different methods for computing the deflection of the full foil structure. The rotor-bearing model is also validated against experimental and theoretical results in the literature.

  4. Development of borehole sealing technology

    International Nuclear Information System (INIS)

    Shimada, Kuniaki; Abe, Kenichi; Tanada, Masuakira; Fujii, Mitsuru

    2004-03-01

    As a part of the geoscientific research in JNC Tono Geoscience Center, we are conducting the borehole investigation as a method of surveying techniques to gain an understanding of geological environment characterization (geology/geological structure, rock hydraulic characteristics, ground water geochemical characteristics and rock mechanics) from surface to deep underground. The borehole for the borehole investigation is used for monitoring hole after the borehole investigation. Since the borehole may act as a passage of groundwater flow and disturb the geological environment artificially, it has to be sealed in finally. Moreover, the hydraulic testing and the geochemical analysis of groundwater that be conducted in the zones injected some kind of lost circulation materials might be impacted on the accuracy of test result. The actual technologies regarding to these themes was researched and evaluated. In the second step, clarification of problems and procedure of R and D for solution of these problems was examined. In order to estimate the effect of lost circulation materials on hydraulic testing, a laboratory test of borehole behavior was performed using a scale model that consisted of a borehole and a water-loss zone. In this test, we found out that the lost circulation material was desorbed from the water-loss zone by back-flow action. It was proved by the test that there is little influence from lost circulation materials on hydraulic testing. Investigation regarding borehole sealing technology was conducted in literature search and interview to overseas researchers. In consequent, three kinds of materials - bentonite clay, bentonite pellet, and ethanol bentonite, were selected as effective sealing material. Moreover, five kinds of methods were selected as effective sealing methods. In water permeability test of sealing material, three kinds of sealing materials indicated lower permeability - order of 10 -11 m/sec, and it was evaluated that it could be worked

  5. Observation of transient lattice vacancies produced during high-energy ion irradiation of Ni foils

    International Nuclear Information System (INIS)

    Tsuchida, Hidetsugu; Iwai, Takeo; Awano, Misa; Kishida, Mutsumi; Katayama, Ichiro; Jeong, Sun-Chang; Ogawa, Hidemi; Sakamoto, Naoki; Komatsu, Masao; Itoh, Akio

    2007-01-01

    Real-time positron annihilation spectroscopy has been applied for the first time for the investigation of lattice vacancies produced during ion irradiation. Measurements were performed for thin nickel foils irradiated with 2.5 MeV C ions. Doppler broadenings of positron annihilation γ-rays were measured alternately during beam-on and beam-off conditions. It was found that the Doppler broadening line-shape parameter measured during irradiation is larger than those obtained before and after irradiation. This evidently implies that transient or non-survivable vacancy defects are produced during ion irradiation. On the other hand, no such significant change in the line-shape parameter was observed for other face-centred-cubic metal forms of aluminium

  6. Dose reader of dosimetric foil; Czytnik dawki folii dozymetrycznej

    Energy Technology Data Exchange (ETDEWEB)

    Machaj, B.; Strzalkowski, J.; Smolko, K.

    1997-12-31

    Read out the absorbance of a dosimetric foil is accomplished by two beam spectrophotometer. Such a solution makes possible the compensation of light source instabilities and ensures higher stability of the dose reader. The error of absorbance measurement caused by the instabilities does not exceed 0.0004 A. (author). 3 refs, 3 figs.

  7. Tribalism as a Foiled Factor of Africa Nation-Building

    Science.gov (United States)

    Okogu, J. O.; Umudjere, S. O.

    2016-01-01

    This paper tends to examine tribalism as a foiled factor on Africa nation-building and proffers useful tips to salvaging the Africa land from this deadly social problem. Africans in times past had suffered enormous attacks, injuries, losses, deaths, destruction of properties and human skills and ideas due to the presence of tribalistic views in…

  8. Secret in the Margins: Rutherford's Gold Foil Experiment

    Science.gov (United States)

    Aydin, Sevgi; Hanuscin, Deborah L.

    2011-01-01

    In this article, the authors describe a lesson that uses the 5E Learning Cycle to help students not only understand the atomic model but also how Ernest Rutherford helped develop it. The lesson uses Rutherford's gold foil experiment to focus on three aspects of the nature of science: the empirical nature of science, the tentativeness of scientific…

  9. Foil Bearing Starting Considerations and Requirements for Rotorcraft Engine Applications

    Science.gov (United States)

    Radil, Kevin C.; DellaCorte, Christopher

    2009-01-01

    Foil gas bearings under development for rotorcraft-sized, hot core engine applications have been susceptible to damage from the slow acceleration and rates typically encountered during the pre-ignition stage in conventional engines. Recent laboratory failures have been assumed to be directly linked to operating foil bearings below their lift-off speed while following conventional startup procedures for the engines. In each instance, the continuous sliding contact between the foils and shaft was believed to thermally overload the bearing and cause the engines to fail. These failures highlight the need to characterize required acceleration rates and minimum operating speeds for these applications. In this report, startup experiments were conducted with a large, rotorcraft engine sized foil bearing under moderate load and acceleration rates to identify the proper start procedures needed to avoid bearing failure. The results showed that a bearing under a 39.4 kPa static load can withstand a modest acceleration rate of 500 rpm/s and excessive loitering below the bearing lift-off speed provided an adequate solid lubricant is present.

  10. The Visualization of Infrared Radiation Using Thermal Sensitive Foils

    Science.gov (United States)

    Bochnícek, Zdenek

    2013-01-01

    This paper describes a set of demonstration school experiments where infrared radiation is detected using thermal sensitive foils. The possibility of using standard glass lenses for infrared imaging is discussed in detail. It is shown that with optic components made from glass, infrared radiation up to 2.5 µm of wavelength can be detected. The…

  11. Evaluation of Alumina-Forming Austenitic Foil for Advanced Recuperators

    Energy Technology Data Exchange (ETDEWEB)

    Pint, Bruce A [ORNL; Brady, Michael P [ORNL; Yamamoto, Yukinori [ORNL; Santella, Michael L [ORNL; Maziasz, Philip J [ORNL; Matthews, Wendy [Capstone Turbines

    2011-01-01

    A corrosion- and creep-resistant austenitic stainless steel has been developed for advanced recuperator applications. By optimizing the Al and Cr contents, the alloy is fully austenitic for creep strength while allowing the formation of a chemically stable external alumina scale at temperatures up to 900 C. An alumina scale eliminates long-term problems with the formation of volatile Cr oxy-hydroxides in the presence of water vapor in exhaust gas. As a first step in producing foil for primary surface recuperators, three commercially cast heats have been rolled to 100 m thick foil in the laboratory to evaluate performance in creep and oxidation testing. Results from initial creep testing are presented at 675 C and 750 C, showing excellent creep strength compared with other candidate foil materials. Laboratory exposures in humid air at 650 800 C have shown acceptable oxidation resistance. A similar oxidation behavior was observed for sheet specimens of these alloys exposed in a modified 65 kW microturbine for 2871 h. One composition that showed superior creep and oxidation resistance has been selected for the preparation of a commercial batch of foil. DOI: 10.1115/1.4002827

  12. Factors affecting use of fission foils as dosimetry sensors

    International Nuclear Information System (INIS)

    Griffin, P.J.; Vehar, D.W.; Kelly, J.G.; Holm, C.V.

    1996-01-01

    Fission foils are commonly used as dosimetry sensors. They play a very important role in neutron spectrum determinations. This paper provides a combination of experimental measurements and calculations to quantify the importance and synergy of several factors that affect the fission response of a dosimeter. Only when these effects are properly treated can fission dosimeters be used with sufficient fidelity

  13. Validation of calculated self-shielding factors for Rh foils

    Science.gov (United States)

    Jaćimović, R.; Trkov, A.; Žerovnik, G.; Snoj, L.; Schillebeeckx, P.

    2010-10-01

    Rhodium foils of about 5 mm diameter were obtained from IRMM. One foil had thickness of 0.006 mm and three were 0.112 mm thick. They were irradiated in the pneumatic transfer system and in the carousel facility of the TRIGA reactor at the Jožef Stefan Institute. The foils were irradiated bare and enclosed in small cadmium boxes (about 2 g weight) of 1 mm thickness to minimise the perturbation of the local neutron flux. They were co-irradiated with 5 mm diameter and 0.2 mm thick Al-Au (0.1%) alloy monitor foils. The resonance self-shielding corrections for the 0.006 and 0.112 mm thick samples were calculated by the Monte Carlo simulation and amount to about 10% and 60%, respectively. The consistency of measurements confirmed the validity of self-shielding factors. Trial estimates of Q0 and k0 factors for the 555.8 keV gamma line of 104Rh were made and amount to 6.65±0.18 and (6.61±0.12)×10 -2, respectively.

  14. Dynamic environmental control mechanisms for pneumatic foil constructions

    Science.gov (United States)

    Flor, Jan-Frederik; Wu, Yupeng; Beccarelli, Paolo; Chilton, John

    2017-11-01

    Membrane and foil structures have become over the last decades an attractive alternative to conventional materials and building systems with increasing implementation in different typologies and scale. The development of transparent, light, flexible and resistant materials like Ethylene Tetrafluoroethylene (ETFE) has triggered a rethinking of the building envelope in the building industry towards lightweight systems. ETFE foil cushions have proven to fulfil the design requirements in terms of structural efficiency and aesthetic values. But the strategies to satisfy increasing demands of energy efficiency and comfort conditions are still under development. The prediction and manipulation of the thermo-optical behaviour of ETFE foil cushion structures currently remain as one of the main challenges for designers and manufacturers. This paper reviews ongoing research regarding the control of the thermo-optical performance of ETFE cushion structures and highlights challenges and possible improvements. An overview of different dynamic and responsive environmental control mechanisms for multilayer foil constructions is provided and the state of the art in building application outlined by the discussion of case studies.

  15. Low-energy electron beams through ultra-thin foils, applications for electron microscopy

    NARCIS (Netherlands)

    Van Aken, R.H.

    2005-01-01

    This thesis has discussed two electron microscopy applications that make use of ultra-thin foils: the tunnel junction emitter and the low-energy foil corrector. Both applications have in common that the electron beam is sent through the thin foil at low energy. Part of the electrons will scatter in

  16. 78 FR 28577 - Notification of Proposed Production Activity, LLFlex, LLC, Subzone 29J (Foil Backed Paperboard...

    Science.gov (United States)

    2013-05-15

    ... Foreign-Trade Zones Board Notification of Proposed Production Activity, LLFlex, LLC, Subzone 29J (Foil...) was received on May 6, 2013. The subzone currently has authority to produce aluminum foil liner stock. The current request would add foil backed paperboard to the list of approved finished products...

  17. Wake visualization of a heaving and pitching foil in a soap film

    NARCIS (Netherlands)

    Muijres, F.T.; Lentink, D.

    2007-01-01

    Many fish depend primarily on their tail beat for propulsion. Such a tail is commonly modeled as a two-dimensional flapping foil. Here we demonstrate a novel experimental setup of such a foil that heaves and pitches in a soap film. The vortical flow field generated by the foil correlates with

  18. Spray sealing: A breakthrough in integral fuel tank sealing technology

    Science.gov (United States)

    Richardson, Martin D.; Zadarnowski, J. H.

    1989-11-01

    In a continuing effort to increase readiness, a new approach to sealing integral fuel tanks is being developed. The technique seals potential leak sources by spraying elastomeric materials inside the tank cavity. Laboratory evaluations project an increase in aircraft supportability and reliability, an improved maintainability, decreasing acquisition and life cycle costs. Increased usable fuel volume and lower weight than conventional bladders improve performance. Concept feasibility was demonstrated on sub-scale aircraft fuel tanks. Materials were selected by testing sprayable elastomers in a fuel tank environment. Chemical stability, mechanical properties, and dynamic durability of the elastomer are being evaluated at the laboratory level and in sub-scale and full scale aircraft component fatigue tests. The self sealing capability of sprayable materials is also under development. Ballistic tests show an improved aircraft survivability, due in part to the elastomer's mechanical properties and its ability to damp vibrations. New application equipment, system removal, and repair methods are being investigated.

  19. Harbour seals (Phoca vitulina and rehabilitation

    Directory of Open Access Journals (Sweden)

    Nynke Osinga

    2010-09-01

    Full Text Available Throughout the past few decades, rehabilitation of seals has become an activity that is anchored in the present day society of many countries. Seals are primarily rehabilitated to help individual animals in distress. At the same time, the release of seals which would have otherwise died can be considered as a contribution to the population. Most rehabilitated seals are animals under one year of age. They are mainly orphans, weaned seals with complications and seals with a parasiticbronchopneumonia. For the optimal handling of seals and their diseases, centralised operations with quality standards are essential. Rehabilitation provides an instrument to monitor the health of the seal population and its ecosystem. Changes in stranding trends or the appearance of new diseases can be monitored. Moreover, rehabilitation is important to show the general public thestate of the marine environment. In the Netherlands there is significant social support for the rehabilitation of seals. Experience obtained with seal care is of importance in countries where urgent help of threatened seal species is required. Here individual seals are also ambassadors to raise support for the protection of this species in general. Given that the anthropogenic impact on the seals and their environment is extensive in the Wadden Sea, rehabilitation centres can compensate the consequences of this impact on individual seals as well as the population as a whole.

  20. Turbine interstage seal with self-balancing capability

    Energy Technology Data Exchange (ETDEWEB)

    Mills, Jacob A; Jones, Russell B; Sexton, Thomas D

    2017-09-26

    An interstage seal for a turbine of a gas turbine engine, the interstage seal having a seal carrier with an axial extending seal tooth movable with a stator of the engine, and a rotor with a seal surface that forms the interstage seal with the seal tooth, where a magnetic force produced by two magnets and a gas force produced by a gas pressure acting on the seal carrier forms a balancing force to maintain a close clearance of the seal without the seal tooth contacting the rotor seal surfaces during engine operation. In other embodiments, two pairs of magnets produce first and second magnetic forces that balance the seal in the engine.

  1. Monolithic LTCC seal frame and lid

    Energy Technology Data Exchange (ETDEWEB)

    Krueger, Daniel S.; Peterson, Kenneth A.; Stockdale, Dave; Duncan, James Brent; Riggs, Bristen

    2016-06-21

    A method for forming a monolithic seal frame and lid for use with a substrate and electronic circuitry comprises the steps of forming a mandrel from a ceramic and glass based material, forming a seal frame and lid block from a ceramic and glass based material, creating a seal frame and lid by forming a compartment and a plurality of sidewalls in the seal frame and lid block, placing the seal frame and lid on the mandrel such that the mandrel fits within the compartment, and cofiring the seal frame and lid block.

  2. EBR-II rotating plug seal maintenance

    International Nuclear Information System (INIS)

    Allen, K.J.

    1986-01-01

    The EBR-II rotating plug seals require frequent cleaning and maintenance to keep the plugs from sticking during fuel handling. Time consuming cleaning on the cover gas and air sides of the dip ring seal is required to remove oxidation and sodium reaction products that accumulate and stop plug rotation. Despite severely limited access, effective seal cleaning techniques have removed 11 800 lb (5 352 kg) of deposits from the seals since 1964. Temperature control modifications and repairs have also required major maintenance work. Suggested seal design recommendations could significantly reduce maintenance on future similar seals

  3. Numerical studies on the interaction between two parallel D-cylinder and oscillated foil

    Science.gov (United States)

    Chao, Li-Ming; Zhang, Dong; Cao, Yong-Hui; Pan, Guang

    2018-02-01

    To understand the interaction between the oscillated body and oncoming vortex, some numerical studies have been conducted on a system including two parallel D-cylinder and one oscillated foil in this paper. It is found that the distance between parallel D-cylinder and oscillated foil would play a key role in affecting the change regulation of thrust generation of oscillated foil, and the kinematics of oscillated foil would determine the value of propulsive thrust, the gap between two parallel D-cylinder would only affect the hydrodynamic performance of oscillated foil at intermediate conditions.

  4. Studies of PMMA sintering foils with and without coating by magnetron sputtering Pd

    Science.gov (United States)

    Cutroneo, M.; Mackova, A.; Torrisi, L.; Vad, K.; Csik, A.; Ando', L.; Svecova, B.

    2017-09-01

    Polymethylmethacrylate thin foils were prepared by using physical and chemical processes aimed at changing certain properties. The density and the optical properties were changed obtaining clear and opaque foils. DC magnetron sputtering method was used to cover the foils with thin metallic palladium layers. The high optical absorbent foils were obtained producing microstructured PMMA microbeads with and without thin metallic coatings. Rutherford Backscattering Spectroscopy, optical investigation and microscopy were employed to characterize the prepared foils useful in the field study of laser-matter interaction.

  5. Measurements of laser generated soft X-ray emission from irradiated gold foils

    Energy Technology Data Exchange (ETDEWEB)

    Davis, J. S.; Keiter, P. A.; Klein, S. R.; Drake, R. P.; Shvarts, D. [University of Michigan, 2455 Hayward St., Ann Arbor, Michigan 48109 (United States); Frank, Y.; Raicher, E.; Fraenkel, M. [Soreq Nuclear Research Center, Yavne (Israel)

    2016-11-15

    Soft x-ray emission from laser irradiated gold foils was measured at the Omega-60 laser system using the Dante photodiode array. The foils were heated with 2 kJ, 6 ns laser pulses and foil thicknesses were varied between 0.5, 1.0, and 2.0 μm. Initial Dante analysis indicates peak emission temperatures of roughly 100 eV and 80 eV for the 0.5 μm and 1.0 μm thick foils, respectively, with little measurable emission from the 2.0 μm foils.

  6. Sealed source peer review plan

    International Nuclear Information System (INIS)

    Feldman, Alexander; Leonard, Lee; Burns, Ron

    2009-01-01

    Sealed sources are known quantities of radioactive materials that have been encapsulated in quantities that produce known radiation fields. Sealed sources have multiple uses ranging from instrument calibration sources to sources that produce radiation fields for experimental applications. The Off-Site Source Recovery (OSR) Project at Los Alamos National Laboratory (LANL), created in 1999, under the direction of the Waste Management Division of the U.S. Department of Energy (DOE) Albuquerque has been assigned the responsibility to recover and manage excess and unwanted radioactive sealed sources from the public and private sector. LANL intends to ship drums containing qualified sealed sources to the Waste Isolation Pilot Plant (WIPP) for disposal. Prior to shipping, these drums must be characterized with respect to radiological content and other parameters. The U. S. Environmental Protection Agency (EPA) requires that ten radionulcides be quantified and reported for every container of waste to be disposed in the WIPP. The methods traditionally approved by the EPA include non-destructive assay (NDA) in accordance with Appendix A of the Contact-Handled Transuranic Waste Acceptance Criteria for the Waste Isolation Pilot Plant (DOE, 2002) (CH WAC). However, because of the nature and pedigree of historical records for sealed sources and the technical infeasibility of performing NDA on these sources, LANL proposes to characterize the content of these waste drums using qualified existing radiological data in lieu of direct measurement. This plan describes the process and documentation requirements for the use of the peer review process to qualify existing data for sealed radiological sources in lieu of perfonning radioassay. The peer review process will be performed in accordance with criteria provided in 40 CFR (section) 194.22 which specifies the use of the NUREG 1297 guidelines. The plan defines the management approach, resources, schedule, and technical requirements

  7. Dual scattering foil design for poly-energetic electron beams.

    Science.gov (United States)

    Kainz, K K; Antolak, J A; Almond, P R; Bloch, C D; Hogstrom, K R

    2005-03-07

    The laser wakefield acceleration (LWFA) mechanism can accelerate electrons to energies within the 6-20 MeV range desired for therapy application. However, the energy spectrum of LWFA-generated electrons is broad, on the order of tens of MeV. Using existing laser technology, the therapeutic beam might require a significant energy spread to achieve clinically acceptable dose rates. The purpose of this work was to test the assumption that a scattering foil system designed for a mono-energetic beam would be suitable for a poly-energetic beam with a significant energy spread. Dual scattering foil systems were designed for mono-energetic beams using an existing analytical formalism based on Gaussian multiple-Coulomb scattering theory. The design criterion was to create a flat beam that would be suitable for fields up to 25 x 25 cm2 at 100 cm from the primary scattering foil. Radial planar fluence profiles for poly-energetic beams with energy spreads ranging from 0.5 MeV to 6.5 MeV were calculated using two methods: (a) analytically by summing beam profiles for a range of mono-energetic beams through the scattering foil system, and (b) by Monte Carlo using the EGS/BEAM code. The analytic calculations facilitated fine adjustments to the foil design, and the Monte Carlo calculations enabled us to verify the results of the analytic calculation and to determine the phase-space characteristics of the broadened beam. Results showed that the flatness of the scattered beam is fairly insensitive to the width of the input energy spectrum. Also, results showed that dose calculated by the analytical and Monte Carlo methods agreed very well in the central portion of the beam. Outside the useable field area, the differences between the analytical and Monte Carlo results were small but significant, possibly due to the small angle approximation. However, these did not affect the conclusion that a scattering foil system designed for a mono-energetic beam will be suitable for a poly

  8. Self-Sealing Cryogenic Fitting

    Science.gov (United States)

    Jia, Lin Xiang; Chow, Wen Lung; Moslemian, Davood; Lin, Gary; Melton, Greg

    1994-01-01

    Self-sealing fitting for cryogenic tubes remains free of leakage from room temperature to liquid-helium temperature even at internal pressure as high as 2.7 MPa. Fitting comprises parts made of materials with different coefficients of thermal expansion to prevent leakage gaps from forming as temperature decreases. Consists of coupling nut, two flared tube ends, and flared O-ring spacer. Spacer contracts more than tube ends do as temperature decreases. This greater contraction seals tube ends more tightly, preventing leakage.

  9. J-2X Fuel Pump Impeller Seal Simulations

    Science.gov (United States)

    Schmauch, Preston B.; West, Jeffrey S.

    2011-01-01

    The J-2X engine was originally designed for the upper stage of the previously cancelled Crew Launch Vehicle. Although the Crew Launch Vehicle was cancelled the J-2X engine, which is currently undergoing hot-fire testing, may be used on future programs. The J-2X engine is a direct descendent of the J-2 engine which powered the upper stage during the Apollo program. Many changes including a thrust increase from 230K to 294K lbf have been implemented in this engine. The rotor-dynamic stability of the fuel turbopump is highly dependent on the tangential velocity of the fluid as it enters the the front face impeller seal. Rotor-dynamic analysis predicts that a much lower tangential velocity will be required for stability than was needed for previous engines. The geometry at the seal entrance for this engine is very complex and vastly different than previous engines. In order to better determine the fluid dynamics and tangential velocity in this seal several CFD simulations were performed. The results of these simulations show that for this seal geometry a great reduction in the tangential velocity is to be expected. The simulations also provided insight into methods that could be employed to drive the swirl velocity to near zero. Unsteady and time-averaged results of several simulations will be presented.

  10. Seals in motion. How movements drive population development of harbour seals and grey seals in the North Sea

    OpenAIRE

    Brasseur, S.M.J.M.

    2017-01-01

    The harbour seal Phoca vitulina and the grey seal Halichoerus grypus have been inhabitants of the Wadden Sea since millennia. Prehistoric findings indicate the presence of both species around 5000 BC. This changed dramatically in the mid Middle-Ages as around 1500 AC, the grey seal disappeared from the Wadden Sea as a consequence of persecution. With growing hunting pressure, especially in the 20th century and concurrent habitat destruction and pollution, the harbour seals reached all time lo...

  11. Simultaneous laser cutting and welding of metal foil to edge of a plate

    Science.gov (United States)

    Pernicka, John C.; Benson, David K.; Tracy, C. Edwin

    1996-01-01

    A method of welding an ultra-thin foil to the edge of a thicker sheet to form a vacuum insulation panel comprising the steps of providing an ultra-thin foil having a thickness less than 0.002, providing a top plate having an edge and a bottom plate having an edge, clamping the foil to the edge of the plate wherein the clamps act as heat sinks to distribute heat through the foil, providing a laser, moving the laser relative to the foil and the plate edges to form overlapping weld beads to weld the foil to the plate edges while simultaneously cutting the foil along the weld line formed by the overlapping beads.

  12. Apollo Seals: A Basis for the Crew Exploration Vehicle Seals

    Science.gov (United States)

    Finkbeiner, Joshua R.; Dunlap, Patrick H., Jr.; Steinetz, Bruce M.; Daniels, Christopher C.

    2007-01-01

    NASA s Vision for Space Exploration Replace the Space Shuttle for missions to ISS. Return to the Moon. Allow manned exploration of Mars. Apollo-like configuration. Blunt-body heat shield. Conical backshell. CEV requires seal development. Prevent ingestion of reentry gases. Prevent loss of habitable atmosphere.

  13. HMSRP Hawaiian Monk Seal Handling Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains records for all handling and measurement of Hawaiian monk seals since 1981. Live seals are handled and measured during a variety of events...

  14. Legacy HMSRP Hawaiian Monk Seals Observers

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set documents observers that have collected monk seal data as part of the ongoing monk seal population assessment efforts by PSD personnel and cooperating...

  15. HMSRP Hawaiian Monk Seal Entanglement data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The data set contains records of all entanglements of Hawaiian monk seals in marine debris. The data set comprises records of seals entangled by derelict fishing...

  16. HMSRP Hawaiian Monk Seal Telemetry Tag Deployments

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This project investigates foraging behavior of Hawaiian monk seals by conducting telemetry studies. During these studies, live seals are instrumented with dive...

  17. Legacy HMSRP Hawaiian Monk Seal Ultrasound Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Ultrasound images for measuring the condition of juvenile seals at Laysan Island during 2009-2010, collected when seals were handled as part of the De-Worming Project

  18. HMSRP Hawaiian Monk Seal Crittercam video

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This project investigates foraging behavior of Hawaiian monk seals by conducting telemetry studies. During these studies, live seals are instrumented with dive...

  19. HMSRP Hawaiian Monk Seal Argos Location Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This project investigates foraging behavior of Hawaiian monk seals by conducting telemetry studies. During these studies, live seals are instrumented with satellite...

  20. Seal Apparatus and Methods to Manufacture Thereof

    Science.gov (United States)

    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.

  1. Overview of LIDS Docking Seals Development

    Science.gov (United States)

    Dunlap, Patrick; Steinetz, Bruce; Daniels, Christopher

    2009-01-01

    GRC is supporting JSC by developing LIDS main interface seals Seal development and testing is occurring at both sub-scale and full-scale levels: a) Small-scale tests performed to define seal materials and evaluate exposure to space environments. b) Medium-scale testing: 1) Permits evaluation of candidate seal designs at faster pace than for full-scale seals. 2) Leak rates and loads can be scaled up to full-scale for indication of seal performance. c) Full-scale test rigs used for seal development and flight qualification tests and to assess on-orbit anomalies if needed. GRC responsible for delivering flight hardware seals to JSC approx.2013 for integration into LIDS flight units.

  2. 〈情報学科〉均衡型(C_9, C_14)-Foil デザイン

    OpenAIRE

    潮, 和彦

    2012-01-01

    In graph theory, the decomposition problem of graphs is a very important topic. Various type of decompositions of many graphs can be seen in the literature of graph theory. This paper gives balanced (C_9, C_14)-foil designs, balanced C_23-foil designs, balanced C_46-foil designs, balanced C_69-foil designs, balanced C_92-foil designs, balanced C_115-foil designs, balanced C_138-foil designs, balanced C_161-foil designs,balanced C_184-foil designs,balanced C207-foil designs, balanced C_230-fo...

  3. Thrombogenicity tests on ar-irradiated polycarbonate foils

    International Nuclear Information System (INIS)

    Trindade, Gustavo F.; Rizzutto, Marcia A.; Silva, Tiago F.; Moro, Marcos V.; Added, Nemitala; Tabacniks, Manfredo H.; Cunha, Tatiana F.; Higa, Olga Z.

    2013-01-01

    Understanding polymer surface properties is extremely important for the most wide range of their applications, from basic coating to the most complex composites and biomaterials. Low energy ion beam irradiation of polymer can improve such surface properties. By modifying its surface biocompatibility, polymers are excellent candidates for biomaterials, due to its malleability and low weight, when compared to metals. In this work, we irradiated 30-μm Bisphenol-A Polycarbonate foils with 23-keV Argon ion beam at six different doses. Aluminium foils were simultaneously irradiated in order to measure the doses by Rutherford Backscattering Spectroscopy. The surface modifications after the argon ion beam irradiation were analyzed by water contact angle measurements and atomic force microscopy. Platelet adhesion tests were used in order to investigate thrombogenicity, showing a growing tendency with the irradiated Argon dose. (author)

  4. Gas Foil Bearing Technology Advancements for Closed Brayton Cycle Turbines

    Science.gov (United States)

    Howard, Samuel A.; Bruckner, Robert J.; DellaCorte, Christopher; Radil, Kevin C.

    2007-01-01

    Closed Brayton Cycle (CBC) turbine systems are under consideration for future space electric power generation. CBC turbines convert thermal energy from a nuclear reactor, or other heat source, to electrical power using a closed-loop cycle. The operating fluid in the closed-loop is commonly a high pressure inert gas mixture that cannot tolerate contamination. One source of potential contamination in a system such as this is the lubricant used in the turbomachine bearings. Gas Foil Bearings (GFB) represent a bearing technology that eliminates the possibility of contamination by using the working fluid as the lubricant. Thus, foil bearings are well suited to application in space power CBC turbine systems. NASA Glenn Research Center is actively researching GFB technology for use in these CBC power turbines. A power loss model has been developed, and the effects of a very high ambient pressure, start-up torque, and misalignment, have been observed and are reported here.

  5. Microcutting and forming of thin aluminium foils for MEMS

    DEFF Research Database (Denmark)

    Damsgaard, Christian Danvad; Mortensen, Dennis; Rombach, Pirmin

    2011-01-01

    This paper presents a simple procedure for simultaneous cutting and forming of thin Al foils for use in MEMS components. The procedure makes use of scaled down macroscopic sheet forming and cutting techniques by using a hydraulic press, a soft counterpart, and a microfabricated stamp tool....... The relation between applied pressure and forming and cutting features has been characterized for a specific set of stamp geometries and boundary conditions. The results show that 10 μm forming features can be transferred to 4 m thick Al foils, which simultaneously can be cut into products by 25 μm wide cut...... lines. Using the procedure presented in this paper scaled to full 4-8 in. silicon wafer stamp tools, a fast and adequate method for high volume production of MEMS components is obtained. © 2011 American Society of Mechanical Engineers....

  6. Convergent beam thickness determination of thin foil zirconium specimens

    International Nuclear Information System (INIS)

    Cann, C.D.

    1978-07-01

    The use of convergent beam patterns to determine the thickness of zirconium foils observed in the electron microscope has been investigated both theoretically and experimentally. On the basis of many-beam dynamical theory calculations, the [1012], [1013], and [1120] reflections at an accelerating voltage of 100 kV and the [1013], [1120], and [1122] reflections at 200 kV were found most suitable for convergent beam thickness determinations. Experimental convergent beam patterns were obtained in the JEOL-200B electron microscope under two different sets of conditions based on the size of the pattern desired. Computer assisted analysis of the patterns obtained gave foil thicknesses in good agreement with those determined from thickness extinction contours. (author)

  7. Tilted Foils Nuclear Spin Polarization at REX-ISOLDE

    CERN Document Server

    Törnqvist, Hans Toshihide

    2013-08-08

    This thesis will explain and summarize my work and involvement in experiments aimed at producing nuclear spin polarization of post-accelerated beams of ions with the tilted-foils technique at the REX-ISOLDE linear accelerator at CERN. Polarizing the nuclear spin of radioactive beams in particular may provide access to observables which may be difficult to obtain otherwise. Currently, the techniques commonly employed for nuclear spin polarization are restricted to specific nuclides and experimental measurement techniques. Tilted foils polarization may provide a new tool to extend the range of nuclides that can be polarized and the types of experiments that can be performed. The experiments rely not only on the production but also on the method to measure the degree of attained polarization. Two methods will be treated, based on particle scattering in Coulomb excitation that may be utilized for stable beams, and the $\\beta$-NMR that requires $\\beta$-decaying nuclei. The experimental setups and measurements will...

  8. Thrombogenicity tests on ar-irradiated polycarbonate foils

    Energy Technology Data Exchange (ETDEWEB)

    Trindade, Gustavo F.; Rizzutto, Marcia A.; Silva, Tiago F.; Moro, Marcos V.; Added, Nemitala; Tabacniks, Manfredo H., E-mail: g.ferraz@usp.br [Universidade de Sao Paulo (USP), Sao Paulo, SP (Brazil). Inst. de Fisica; Delgado, Adriana O. [Universidade Federal de Sao Carlos (UFSCAR), Sorocaba, SP (Brazil); Cunha, Tatiana F. [Biosintesis P and D do Brasil, Sao Paulo, SP (Brazil); Higa, Olga Z. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil). Centro de Biotecnologia

    2013-07-01

    Understanding polymer surface properties is extremely important for the most wide range of their applications, from basic coating to the most complex composites and biomaterials. Low energy ion beam irradiation of polymer can improve such surface properties. By modifying its surface biocompatibility, polymers are excellent candidates for biomaterials, due to its malleability and low weight, when compared to metals. In this work, we irradiated 30-μm Bisphenol-A Polycarbonate foils with 23-keV Argon ion beam at six different doses. Aluminium foils were simultaneously irradiated in order to measure the doses by Rutherford Backscattering Spectroscopy. The surface modifications after the argon ion beam irradiation were analyzed by water contact angle measurements and atomic force microscopy. Platelet adhesion tests were used in order to investigate thrombogenicity, showing a growing tendency with the irradiated Argon dose. (author)

  9. A new method for alkaline dissolution of uranium metal foil

    International Nuclear Information System (INIS)

    Mondino, A.V.; Wilkinson, M.V.; Manzini, A.C.

    2001-01-01

    In order to develop a production process of 99 Mo by fission of low-enriched uranium, the first purification step, which consists of dissolution of a uranium metal foil target, was studied. It was found that alkaline NaClO gave good results, reaching the dissolution of up to 300 μm of uranium foil. The different conditions for the dissolution were studied and the optimum ones were found. The influence of NaClO and NaOH concentration, temperature, dissolving solution volume per unit of surface and dissolution time were investigated. During this step, a gas identified as H 2 , was generated, and a precipitate characterized as Na 2 U 2 O 7 was observed. A stoichiometric reaction for this uranium dissolution is proposed. (author)

  10. Non Destructive Seal Testing Polymeric Tray

    Science.gov (United States)

    2006-10-01

    School of Enviromental and Biological Science Rutgers, The State University of New Jersey New Brunswick, New Jersey 08903 Principal Investigator...strength, tack seals and seal creep. The following modifications were issued : Jan 20, 2004 0008/01 Add incremental funding to increase total...Technologies”. Most of the “commercial off the shelf” systems are designed to detect seal integrity issues , such as seal contamination, cuts and holes. A

  11. Reactor coolant pump seals: improving their performance

    International Nuclear Information System (INIS)

    Pothier, N.E.; Metcalfe, R.

    1986-06-01

    Large CANDU plants are benefitting from transient-resistant four-year reliable reactor coolant pump seal lifetimes, a direct result of AECL's 20-year comprehensive seal improvement program involving R and D staff, manufacturers, and plant designers and operators. An overview of this program is presented, which covers seal modification design, testing, post-service examination, specialized maintenance and quality control. The relevancy of this technology to Light Water Reactor Coolant Pump Seals is also discussed

  12. Development of simplified rotating plug seal structure

    International Nuclear Information System (INIS)

    Ueta, M.; Ichimiya, M.; Kanaoka, T.; Sekiya, H.; Ueda, S.; Ishibashi, S.

    1991-01-01

    We studied a compact and simplified rotating plug seal structure and conducted experiments for key elements of the concept such us the mechanical seal structure and sodium deposit prevention system. Good characteristics were confirmed for the mechanical seal structure, which utilizes an elastomer seal and thin lathe bearing. Applicability of the density barrier concept was also confirmed as the sodium deposit prevention system. This concept can be applied to actual plants. (author)

  13. Effect of phototherapy with alumunium foil reflectors on neonatal hyperbilirubinemia

    Directory of Open Access Journals (Sweden)

    Tony Ijong Dachlan

    2015-03-01

    Full Text Available Background Neonatal hyperbilirubinemia (NH is one of the most common problems in neonates, but it can be treated with blue light phototherapy. Developing countries with limited medical equipment and funds have difficulty providing effective phototherapy to treat NH, leading to increased risk of bilirubin encephalopathy. Phototherapy with white reflecting curtains can decrease the duration of phototherapy needed to reduce bilirubin levels. Objective To compare the duration of phototherapy needed in neonates with NH who underwent phototherapy with and without aluminum foil reflectors. Methods This open clinical trial was conducted from July to August 2013 at Dr. Hasan Sadikin Hospital, Bandung, Indonesia. The inclusion criteria were term neonates with uncomplicated NH presenting in their first week of life. Subjects were randomized into two groups, those who received phototherapy with or without aluminum foil reflectors. Serum bilirubin is taken at 12th, 24th, 48th hours, then every 24 hours if needed until phototherapy can be stopped according to American Academy of Pediatrics guidelines. The outcome measured was the duration of phototherapy using survival analysis. The difference between the two groups was tested by Gehan method. Results Seventy newborns who fulfilled the inclusion criteria and had similar characteristics were randomized into two groups. The duration of phototherapy needed was significantly less in the group with aluminum foil reflectors than in the group without reflectors [72 vs. 96 hours, respectively, (P<0.01]. Conclusion The required duration of phototherapy with aluminum foil reflectors is significantly less than that of phototherapy without reflectors, in neonates with NH.

  14. Note: Manganin foil sensor for small uniaxial stress

    Science.gov (United States)

    Frampton, M. K.; McLaughlin, N.; Jin, Hu; Zieve, R. J.

    2017-04-01

    We describe a simple manganin foil resistance manometer for uniaxial stress measurements. The manometer functions at low pressures and over a range of temperatures. In this design, no temperature seasoning is necessary although the manometer must be prestressed to the upper end of the desired pressure range. The prestress pressure cannot be increased arbitrarily; irreversibility arising from shear stress limits its range. Attempting larger pressures yields irreproducible resistance measurements.

  15. Dynamic nuclear polarization in thin polymer foils and tubes

    Science.gov (United States)

    van den Brandt, B.; Bunyatova, E. I.; Hautle, P.; Konter, J. A.; Mango, S.

    1995-02-01

    First results of DNP at 2.5 T and below 0.3 K in thin polymer foils and tubes with the chemical composition (CX 2) n, [ X = 1H, 2D, 19F ], doped with TEMPO, are presented. Appreciable polarization of protons, deuterons, and 19F-nuclei were obtained. The samples can be handled at room temperature for several hours, and therefore they are suitable for new applications.

  16. Dynamic nuclear polarization in thin polymer foils and tubes

    Energy Technology Data Exchange (ETDEWEB)

    Brandt, B. van den [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Bunyatova, E.I. [Joint Inst. for Nuclear Research, Dubna (Russian Federation); Hautle, P. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Konter, J.A. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Mango, S. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1995-03-01

    First results of DNP at 2.5 T and below 0.3 K in thin polymer foils and tubes with the chemical composition (CX{sub 2}){sub n}, [X={sup 1}H, {sup 2}D, {sup 19}F], doped with TEMPO, are presented. Appreciable polarizations of protons, deuterons, and {sup 19}F-nuclei were obtained. The samples can be handled at room temperature for several hours, and therefore they are suitable for new applications. ((orig.))

  17. Interaction of positron beams with thin silver foils and surfaces

    International Nuclear Information System (INIS)

    Rysholt Poulsen, M.

    1994-01-01

    Experimental investigations of positron interactions with solid silver and the necessary platform to analyse the data have been presented. The main objective was to study Ps formation at a Ag(100) surface. The different ingredients of the scenario, including thermalization and diffusion of positrons and emission of Ps, were analysed and quantified in whatever way appropriate. The scattering and possible thermalization were described. The parametrization of Monte-Carlo simulated implantation profiles for semi-infinite materials were presented and the applicability of such profiles to thin foils assessed. The latter was done in conjunction with an analysis of experimental data on thermalization and diffusion in 1900 Aa Ag(100) foils. The necessity for MC simulated rather than parametrized implantation profiles was argued. The velocity of thermally desorbed Ps from a Ag(100) surface at ∼800 K appeared to obey and one-dimensional Maxwell Boltzmann distribution multiplied by a velocity dependent factor. More experimental investigations are needed before firm conclusions can be made on the nature of the emission process. The velocity distribution, though, was found to be near-thermal and indicative of the sample temperature. It has been shown that positrons can be converted into Ps atoms in the transmission geometry of a thin 1900 Aa Ag(100) foil with a high efficiency. Furthermore, 61% of the emitted Ps will have a mean velocity of v z =1.2x10 5 m/sec and 39% will have a maximum kinetic energy of 1.5 eV (v z =5.1x10 5 m/sec) at a foil temperature of 800 K, all velocities that are suitable for producing a 'dense' Ps gas target. (EG) 12 refs

  18. Synthetic Graphene Grown by Chemical Vapor Deposition on Copper Foils

    Science.gov (United States)

    2013-04-11

    review the synthesis and properties of CVD -grown graphene , demonstrated using examples pimarily from our work in re- cent years. Particularly, we will...promise for many applica- tions.60 Compared to other large-scale graphene synthesis methods, CVD -grown graphene on copper foil substrates has been shown to...methods. Despite the fact that CVD - grown graphene films may be less perfect (the presence of domain boundaries, defects, wrinkles, impurities and

  19. A Manganin Foil Sensor for Small Uniaxial Stress

    OpenAIRE

    Frampton, M. K.; McLaughlin, N.; Jin, Hu; Zieve, R. J.

    2017-01-01

    We describe a simple manganin foil resistance manometer for uniaxial stress measurements. The manometer functions at low pressures and over a range of temperatures. In this design no temperature seasoning is necessary, although the manometer must be prestressed to the upper end of the desired pressure range. The prestress pressure cannot be increased arbitrarily; irreversibility arising from shear stress limits its range. Attempting larger pressures yields irreproducible resistance measurements.

  20. Ablative acceleration of thin foil targets by intense proton beams

    International Nuclear Information System (INIS)

    Miyamoto, S.; Ozaki, T.; Imasaki, K.; Higaki, S.; Nakai, S.

    1981-01-01

    A focused proton beam of up to 2 x 10 10 w/cm 2 was obtained using pinch-reflex ion diode connected to Reiden IV generator. Experiments of beam target interaction have been done using thin foil targets. In this power range the interaction was explained classically. The experimental dependence of ablation pressure on proton beam intensity was obtained as P sub(a) = 3 x 10 -3 I sup(0.7) bar (I in w/cm 2 ). (author)

  1. The (ineffectiveness of green seals on consumer behavior: a experimental study [doi: 10.21529/RECADM.2017003

    Directory of Open Access Journals (Sweden)

    Taís Pasquotto Andreoli

    2017-09-01

    Full Text Available The objective of the study was to analyze consumers' perceptions about green seals, according to how well known these seals are and to their own profile of green consumption. Therefore, a theoretical reference was made on sustainable consumption, as well as on the application of green seals in the perspective of green marketing. The method adopted was a hypothetical-deductive approach, carried out through two experiments (one online and the other face-to-face, both with factorial design 2 (true and well-known green seal versus false seal and nothing known x 2 very sustainable versus low sustainable consumer profile. In view of the results obtained, four main discussions could be made, such as the possibility of greenwashing due to the clear mention of environmental aspects, either in relation to the seal itself or to the statements underlying it, the ineffectiveness of adopting green seals and influence of this ineffectiveness even in consumers who reported having a more sustainable consumption profile.   Keywords Sustainable consumption; Green marketing; Green seals; Experimental research; Greenwashing.

  2. Acoustic resonance spectroscopy intrinsic seals

    International Nuclear Information System (INIS)

    Olinger, C.T.; Burr, T.; Vnuk, D.R.

    1994-01-01

    We have begun to quantify the ability of acoustic resonance spectroscopy (ARS) to detect the removal and replacement of the lid of a simulated special nuclear materials drum. Conceptually, the acoustic spectrum of a container establishcs a baseline fingerprint, which we refer to as an intrinsic seal, for the container. Simply removing and replacing the lid changes some of the resonant frequencies because it is impossible to exactly duplicate all of the stress patterns between the lid and container. Preliminary qualitative results suggested that the ARS intrinsic seal could discriminate between cases where a lid has or has not been removed. The present work is directed at quantifying the utility of the ARS intrinsic seal technique, including the technique's sensitivity to ''nuisance'' effects, such as temperature swings, movement of the container, and placement of the transducers. These early quantitative tests support the potential of the ARS intrinsic seal application, but also reveal a possible sensitivity to nuisance effects that could limit environments or conditions under which the technique is effective

  3. Flapping propulsion with side-by-side pitching foils

    Science.gov (United States)

    Huera-Huarte, Francisco

    2016-11-01

    Fish schools are one of the most common types of collective behaviour observed in nature. One of the reasons why fish swim in groups, is to reduce the cost of transport of the school. In this work we explore the propulsive performance of two foils flapping in a symmetric configuration, i.e. with an out-of-phase flapping motion. Direct thrust measurements and Particle Image Velocimetry (PIV) allowed a detailed examination of the forces and the wake generated by the system, for different kinematics (swept angles and frequencies) and shaft separations. For certain specific cases, volumetric PIV shows major differences on how the different structures in the wake of the system evolve, depending on the imposed kinematics and the side-by-side separation between the foils. Results obtained will be compared against data produced with isolated flapping foils with similar imposed kinematics, with the aim to better understand the interactions between both and the performance of the system as a whole. The author would like to acknowledge the financial support provided by the Spanish Ministerio de Economia y competitividad (MINECO) through Grant DPI2015-71645-P.

  4. Design of organic complementary circuits and systems on foil

    CERN Document Server

    Abdinia, Sahel; Cantatore, Eugenio

    2015-01-01

    This book describes new approaches to fabricate complementary organic electronics, and focuses on the design of circuits and practical systems created using these manufacturing approaches. The authors describe two state-of-the-art, complementary organic technologies, characteristics and modeling of their transistors and their capability to implement circuits and systems on foil. Readers will benefit from the valuable overview of the challenges and opportunities that these extremely innovative technologies provide. ·         Demonstrates first circuits implemented using specific complementary organic technologies, including first printed analog to digital converter, first dynamic logic on foil and largest complementary organic circuit ·         Includes step-by-step design from single transistor level to complete systems on foil ·         Provides a platform for comparing state-of-the-art complementary organic technologies and for comparing these with other similar technologies, spec...

  5. Element segregation on the surfaces of pure aluminum foils

    International Nuclear Information System (INIS)

    Zhang Xinming; Liu Jiancai; Tang Jianguo; Li Li; Chen Mingan; Liu Shengdan; Zhu Bing

    2010-01-01

    The surface segregation trend of trace elements in pure aluminum foils was investigated by density functional theory. The model of nine-layer Al(1 0 0) slab substituted partially by trace element atoms was proposed for calculating surface segregation energy. The calculating results show that (i) B, Mg, Si, Ga, Ge, Y, In, Sn, Sb, Pb and Bi exhibit negative segregation energy and possibly move to the surface, while Be, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu and Zr exhibit positive segregation energies and migrated into the bulk; (ii) the segregation energy was found to be related with the covalent radius, the relaxed position at the surface of the substituting atom and the surface energy; (iii) the segregation behavior of trace element generates lots of defects and dislocation, which can increase the initial pitting nucleation sites in the surface of aluminum foils; (iv) the impurity atom concentration was tested with Pb-doped surfaces, the calculated negative segregation energies in all coverage increases rapidly with the Pb coverage. These conclusions are helpful for designing of the chemical composition and to advance the tunnel etching of aluminum foils.

  6. Small incision removal of nylon foil orbital implants.

    Science.gov (United States)

    Liu, Catherine Y; Vemuri, Swapna; Tao, Jeremiah P

    2015-01-01

    To describe a small incision technique for the removal of a nylon foil orbital wall implant. The authors retrospectively reviewed the charts of 9 patients who underwent a minimally invasive anterior orbitotomy for nylon foil explantation. Indications for removal and surgical technique, including size of orbitotomy incision and extent of orbital dissection, were recorded. Motility, globe position, strabismus pre- and post procedure, and complications were also assessed. Photographs, videos, and postoperative imaging were included, when available. The indications for removal were adjacent sinusitis (4 cases), undesirable implant position (3), orbital abscess (1), and adjacent orbital emphysema (1). The removal technique was associated with no changes in motility, globe position, or strabismus postprocedure. The average incision size was 1.1 cm, and the procedure was rapid, usually seconds once the anterior aspect of the implant was exposed and grasped with a hemostat. The dissection in all cases was to the anterior aspect of the implant without a need for deep orbital manipulation. The authors demonstrate through video that the implant folds to exit through a small incision. No adverse events were noted. Nasal endoscopy and radiography demonstrated a fibrous capsule that maintained orbital structure and support. Thin nylon foil implant can be explanted safely and efficiently through a very small incision. The orbit maintains structure and configuration postexplantation in this series.

  7. Simulation of thin aluminium-foil in the packaging industry

    Science.gov (United States)

    Eskil, Andreasson; Lindström, Tommy; Käck, Britta; Malmberg, Christoffer; Asp, Ann-Magret

    2017-10-01

    This work present an approach of how to account for the anisotropic mechanical material behaviour in the simulation models of the thin aluminium foil layer (≈10 µm) used in the Packaging Industry. Furthermore, the experimental results from uniaxial tensile tests are parameterised into an analytical expression and the slope of the hardening subsequently extended way beyond the experimental data points. This in order to accommodate the locally high stresses present in the experiments at the neck formation. An analytical expression, denominated Ramberg-Osgood, is used to describe the non-linear mechanical behaviour. Moreover it is possible with a direct method to translate the experimental uniaxial tensile test results into useful numerical material model parameters in Abaqus™. In addition to this the extended material behaviour including the plastic flow i.e. hardening, valid after onset of localisation, the described procedure can also capture the microscopic events, i.e. geometrical thinning, ongoing in the deformation of the aluminium foil. This method has earlier successfully been applied by Petri Mäkelä for paperboard material [1]. The engineering sound and parameterised description of the mechanical material behaviour facilitates an efficient categorisation of different aluminium foil alloys and aid the identification of the correct anisotropic (RD/TD/45°) mechanical material behaviour derived from the physical testing.

  8. Propulsive performance of pitching foils with variable chordwise flexibility

    Science.gov (United States)

    Zeyghami, Samane; Moored, Keith; Lehigh University Team

    2017-11-01

    Many swimming and flying animals propel themselves efficiently through water by oscillating flexible fins. These fins are not homogeneously flexible, but instead their flexural stiffness varies along their chord and span. Here we seek to evaluate the effect stiffness profile on the propulsive performance of pitching foils. Stiffness profile characterizes the variation in the local fin stiffness along the chord. To this aim, we developed a low order model of a functionally-graded material where the chordwise flexibility is modeled by two torsional springs along the chordline and the stiffness and location of the springs can be varied arbitrarily. The torsional spring structural model is then strongly coupled to a boundary element fluid model to simulate the fluid-structure interactions. Keeping the leading edge kinematics unchanged, we alter the stiffness profile of the foil and allow it to swim freely in response to the resulting hydrodynamic forces. We then detail the dependency of the hydrodynamic performance and the wake structure to the variations in the local structural properties of the foil.

  9. Ergonomics and safety of manual bag sealing.

    NARCIS (Netherlands)

    Groot, M.D. de; Bosch, T.; Eikhout, S.M.; Vink, P.

    2005-01-01

    A variety of seals is used to close bags. Each seal has advantages and disadvantages. For shop assistants sealing bags could be a repetitive physically demanding action. Opening and closing the bags again can cause some discomfort or annoyance for consumers. Besides, it is an activity which can

  10. Annular Pressure Seals and Hydrostatic Bearings

    National Research Council Canada - National Science Library

    San Andres, Luis

    2006-01-01

    ..., in particular those handling large density fluids. Highlights on the bulk-flow analysis of annular seals are given with details on the performance of two water seals long and short, featuring the advantages of an anti-swirl brake to enhance the seal...

  11. 19 CFR 113.25 - Seals.

    Science.gov (United States)

    2010-04-01

    ... signatures of principal and surety, if individuals, and the corporate seal shall be affixed close to the... law of the state in which executed. However, when the charter or governing statute of a corporation requires its acts to be evidenced by its corporate seal, such seal is required. ...

  12. 36 CFR 901.6 - Seal.

    Science.gov (United States)

    2010-07-01

    ... 36 Parks, Forests, and Public Property 3 2010-07-01 2010-07-01 false Seal. 901.6 Section 901.6 Parks, Forests, and Public Property PENNSYLVANIA AVENUE DEVELOPMENT CORPORATION BYLAWS OF THE CORPORATION § 901.6 Seal. The Corporation may adopt a corporate seal which shall have the name of the...

  13. Piston rod seal for a Stirling engine

    Science.gov (United States)

    Shapiro, Wilbur

    1984-01-01

    In a piston rod seal for a Stirling engine, a hydrostatic bearing and differential pressure regulating valve are utilized to provide for a low pressure differential across a rubbing seal between the hydrogen and oil so as to reduce wear on the seal.

  14. Aerodynamic seal assemblies for turbo-machinery

    Science.gov (United States)

    Bidkar, Rahul Anil; Wolfe, Christopher; Fang, Biao

    2015-09-29

    The present application provides an aerodynamic seal assembly for use with a turbo-machine. The aerodynamic seal assembly may include a number of springs, a shoe connected to the springs, and a secondary seal positioned about the springs and the shoe.

  15. Tribological Tuft Testing Candidate Brush Seal Materials

    Science.gov (United States)

    DellaCorte, Chris

    1999-01-01

    This paper presents a tribological tuft test method of candidate brush seal materials in viewgraph form. The goals of the research are: 1) To develop test method to tribologically brush seal materials; 2) To evaluate materials to identify potential improvements and trends; and 3) Guide seal material development and selection.

  16. Improved sealing for in-core systems

    International Nuclear Information System (INIS)

    Dunford, S.

    1989-01-01

    The in-core instrumentation sealing nozzles designed by Framatome have three mechanical seals in series instead of the one traditional seal, and are pressurized by simply tightening up the nozzle covers. They have been installed from the start on all Framatome PWRs, as well as having been backfitted on Belgium and Yugoslavian units and chosen for the Chinese Qinshan plant. (author)

  17. Dampers for Stationary Labyrinth Seals

    Science.gov (United States)

    El-Aini, Yehia; Mitchell, William; Roberts, Lawrence; Montgomery, Stuart; Davis, Gary

    2011-01-01

    Vibration dampers have been invented that are incorporated as components within the stationary labyrinth seal assembly. These dampers are intended to supplement other vibration-suppressing features of labyrinth seals in order to reduce the incidence of high-cycle-fatigue failures, which have been known to occur in the severe vibratory environments of jet engines and turbopumps in which labyrinth seals are typically used. A vibration damper of this type includes several leaf springs and/or a number of metallic particles (shot) all held in an annular seal cavity by a retaining ring. The leaf springs are made of a spring steel alloy chosen, in conjunction with design parameters, to maintain sufficient preload to ensure effectiveness of damping at desired operating temperatures. The cavity is vented via a small radial gap between the retaining ring and seal housing. The damping mechanism is complex. In the case of leaf springs, the mechanism is mainly friction in the slippage between the seal housing and individual dampers. In the case of a damper that contains shot, the damping mechanism includes contributions from friction between individual particles, friction between particles and cavity walls, and dissipation of kinetic energy of impact. The basic concept of particle/shot vibration dampers has been published previously; what is new here is the use of such dampers to suppress traveling-wave vibrations in labyrinth seals. Damping effectiveness depends on many parameters, including, but not limited to, coefficient of friction, mode shape, and frequency and amplitude of vibrational modes. In tests, preloads of the order of 6 to 15 lb (2.72 to 6.8 kilograms) per spring damper were demonstrated to provide adequate damping levels. Effectiveness of shot damping of vibrations having amplitudes from 20 to 200 times normal terrestrial gravitational acceleration (196 to 1,960 meters per square second) and frequencies up to 12 kHz was demonstrated for shot sizes from 0.032 to

  18. Comparative study on two different seal surface structure for reactor pressure vessel sealing behavior

    International Nuclear Information System (INIS)

    Chen Jun; Xiong Guangming; Deng Xiaoyun

    2014-01-01

    The seal surface structure is very important to reactor pressure vessel (RPV) sealing behavior. In this paper, two 3-D RPV sealing analysis finite models have been established with different seal surface structures, in order to study the influence of two structures. The separation of RPV upper and lower flanges, bolt loads and etc. are obtained, which are used to evaluate the sealing behavior of the RPV. Meanwhile, the comparative analysis of safety margin of two seal surface structural had been done, which provides the theoretical basis for RPV seal structure design optimization. (authors)

  19. Immobilisation of southern elephant seals and leopard seals with cyclohexamine anaesthetics and xylazine.

    Science.gov (United States)

    Mitchell, P J; Burton, H R

    1991-10-12

    Ketamine and xylazine were given to 55 southern elephant seals (Mirounga leonina) for stomach lavaging, and to three leopard seals (Hydrurga leptonyx). The elephant seals showed prolonged apnoea and two of them died owing to aspiration of stomach contents. Two of the leopard seals died from unknown causes. Tiletamine and zolazepam were given to five elephant seals and one leopard seal. Two of the elephant seals and the leopard seal died from unknown causes. Xylazine alone was administered to 34 leopard seals. Sedation was poor at low dose rates (less than 1.7 mg/kg) but four of the seals given higher dose rates died owing to the aspiration of stomach contents.

  20. The effects of passive foil flexibility on the energy extraction performance of an oscillating foil operating at low reduced frequencies

    Science.gov (United States)

    Totpal, Alexander D.; Siala, Firas F.; Liburdy, James A.

    2016-11-01

    With a goal to improve energy extraction efficiency from an oscillating foil, direct aerodynamic force measurements are used to study the effect of surface flexibility of an oscillating foil operating in the energy harvesting regime. The experiments are conducted in a closed-loop wind tunnel at a low reduced frequencies range of 0.04-0.06. The pitching amplitude was varied from 45 to 90 degrees and the phase shift between pitching and heaving motions was varied from 30 to 120 degrees. Three different airfoil configurations were tested: fully rigid, flexible leading edge and flexible trailing edge. In addition, phase-locked particle image velocimetry (PIV) measurements were taken at the higher efficiency cases, and are used to help interpret trends seen in the force measurement data. The timing and position of the leading edge vortex along the foil, which has been shown to be crucial to energy extraction, is investigated in order to help explain why certain operating conditions yield larger efficiencies.

  1. Face-to-face: Perceived personal relevance amplifies face processing

    Science.gov (United States)

    Pittig, Andre; Schupp, Harald T.; Alpers, Georg W.

    2017-01-01

    Abstract The human face conveys emotional and social information, but it is not well understood how these two aspects influence face perception. In order to model a group situation, two faces displaying happy, neutral or angry expressions were presented. Importantly, faces were either facing the observer, or they were presented in profile view directed towards, or looking away from each other. In Experiment 1 (n = 64), face pairs were rated regarding perceived relevance, wish-to-interact, and displayed interactivity, as well as valence and arousal. All variables revealed main effects of facial expression (emotional > neutral), face orientation (facing observer > towards > away) and interactions showed that evaluation of emotional faces strongly varies with their orientation. Experiment 2 (n = 33) examined the temporal dynamics of perceptual-attentional processing of these face constellations with event-related potentials. Processing of emotional and neutral faces differed significantly in N170 amplitudes, early posterior negativity (EPN), and sustained positive potentials. Importantly, selective emotional face processing varied as a function of face orientation, indicating early emotion-specific (N170, EPN) and late threat-specific effects (LPP, sustained positivity). Taken together, perceived personal relevance to the observer—conveyed by facial expression and face direction—amplifies emotional face processing within triadic group situations. PMID:28158672

  2. The N250 brain potential to personally familiar and newly learned faces and objects

    Directory of Open Access Journals (Sweden)

    Lara Justine Pierce

    2011-10-01

    Full Text Available Studies employing event-related potentials (ERPs have shown that when participants are monitoring for a novel target face, the presentation of their own face elicits an enhanced negative brain potential in posterior channels approximately 250 ms after stimulus onset. Here, we investigate whether the own-face N250 effect generalizes to other highly familiar objects, specifically, images of the participant’s own dog and own car. In our experiments, participants were asked to monitor for a pre-experimentally unfamiliar target face (Joe, a target dog (Experiment 1: Joe’s Dog or a target car (Experiment 2: Joe’s Car. The target face and object stimuli were presented with non-target foils that included novel face and object stimuli, the participant’s own face, their own dog (Experiment 1 and their own car (Experiment 2. The consistent findings across the two experiments were the following: 1 the N250 potential differentiated the target faces and objects from the non-target face and object foils and 2 despite being non-targets, the own face and own objects produced an N250 response that was equal in magnitude to the target faces and objects by the end of the experiment. Thus, as indicated by its response to personally familiar and recently familiarized faces and objects, the N250 component is a sensitive index of individuated representations in visual memory.

  3. Development of the seal for nuclear material

    International Nuclear Information System (INIS)

    Lu Feng; Lu Zhao; Zhao Yonggang; Zhang Qixin; Xiao Xuefu

    2000-01-01

    Two kinds of double cap metallic seal and an adhesive seal are developed for the purpose of the accounting for and control of nuclear material. Two kinds of double cap metallic seal are made of stainless steel and copper, respectively and the self-locked technique is used. The number and the random pattern are carved out side and in side of a cap, respectively, for the seal. The random pattern carved inside of a cap for seal is taken a picture using numeral camera and memorized in computer. Special software is developed for verification of the random pattern memorized in computer. The adhesive seal is made of special adhesive paper for purpose of security, and a special pattern guarded against falsification is printed on seal paper using ultraviolet fluorescent light technique

  4. Test methods for foil and textile fibre hoses for the rehabilitation of gas piplines; Pruefmethoden fuer Folien- und Gewebeschlaeuche zum Sanieren von Gasleitungen

    Energy Technology Data Exchange (ETDEWEB)

    Driesen, H.E. [Karlsruhe Univ. (T.H.) (Germany). DVGW-Forschungsstelle am Engler-Bunte-Institut

    1995-01-01

    The Standard for ``means for the subsequent sealing of joints of gaspipes laid in the ground`` (DIN 30658) required a supplement, after various processes were developed, not only for sealing the leaking sleeve joints, but for cladding long sections of pipe with foil or woven hoses. The functional tests on sealed sleeve joints taken over largely unchanged were supplemented by specific tests of the cladding, which concern the opening of existing house connection and the production of new ones, the bridging of corrosion damage and unused tee-offs, and for woven hoses the behaviour during pipe fractures with the raising of the maximum permitted working pressure from 1 bar in DIN 30658 to 4 bar. There is a report on the results of a research project financed by DVGW for working out test proceedures and requirements. (orig.) [Deutsch] Die Norm ueber ``Mittel zum nachtraeglichen Abdichten von Verbindungen erdverlegter Gasleitungen`` (DIN 30658) bedurfte einer Ergaenzung, nachdem verschiedene Verfahren entwickelt wurden, nicht nur gezielt die undichten Muffenverbindungen abzudichten, sondern laengere Leitungsabschnitte mit Folien- oder Gewebeschlaeuchen auszukleiden. Die im wesentlichen unveraendert uebernommenen Funktionspruefungen an abgedichteten Muffenverbindungen wurden durch spezifische Pruefungen der Auskleidung ergaenzt, die das Oeffnen bestehender und die Erstellung neuer Hausanschluesse, die Ueberbrueckung von Korrosionsschaeden und stillgelegten Abgaengen sowie bei Gewebeschlaeuchen das Verhalten bei Rohrbruechen bei Anhebung des max. zulaessigen Betriebsdruckes von 1 bar in DIN 30658 auf 4 bar betreffen. Ueber die Ergebnisse eines vom DVGW finanzierten Forschungsvorhabens zur Erarbeitung von Pruefverfahren und Anforderungen wird berichtet. (orig.)

  5. Sealing system for a nuclear reactor

    International Nuclear Information System (INIS)

    McEdwards, J.A.

    1982-01-01

    A nuclear reactor is described which is cooled with a liquid metal and, in particular, the seal for such a nuclear reactor is described. The nuclear reactor includes a vessel, which is closed at the top by a top closure. The top closure consists of a least two components, one of which can rotate. There is an annular gap between the two components. The sealing system in the annular gap consists of at least a first and a second seal which can expand, which are situated in series in the top part of the annular gap. The system also includes an immersed seal: this is arranged in a body made of insulating material. The insulating material body is situated on the underside of the top closure. The immersed seal includes a trough at the lower end of one of the components and a sealing edge, which hangs from the other component and extends downwards into the trough. There is a liquid metal bath in the trough, into which part of the sealing edge projects. The sealing edge has at least one opening above the liquid metal bath. This permits a flow connection between the two spaces on the two sides of the sealing edge, i.e. the space between the immersed seal and the expanding seals on the one hand and the protective gas space within the vessel on the other hand. Further, there is a device by which flushing gas can be introduced into the annular gap between the expanding seals and the sealing edge. The flushing gas is provided to a sufficient extent, so that diffusion of radiaoctive protective gas and sodium vapour upwards to the expanding seals is considerably reduced. The flushing gas mixes with the protective gas in the reactor vessel and can be tapped off there, whereupon it is reprocessed and returned to the vessel. (orig.) [de

  6. Seal dynamics on the Swedish west coast: Scenarios of competition as Baltic grey seal intrude on harbour seal territory

    Science.gov (United States)

    Svensson, Carl Johan

    2012-07-01

    The Kattegat-Skagerrak region on the Swedish west coast is home to an abundant harbour seal population (Phoca vitulina) and a small scattered grey seal population (Halichoerus grypus). In addition, grey seal from the growing population in the Baltic Sea frequently migrate into the Kattegat-Skagerrak. Harbour seals on the west coast of Sweden show relatively high population growth (approximately 9%) compared to the Baltic grey seal in ice-free habitats (approximately 6%), which, in theory, makes harbour seal the stronger competitor of the two in this region. However, incidents of disease in harbour seals that lower population growth are becoming more frequent. These epidemics are primarily caused by the Phocine Distemper Virus (PDV), and may reduce population size with up to 70%. This study models the average development under potential scenarios of competing harbour- and Baltic grey seal populations using Leslie matrices and the Lotka-Volterra model of inter-specific competition. The model is parameterised with previously published data, and resource overlap is incorporated through density dependent pup survival. Using numerical methods short- and long-term abundances are simulated under weak, moderate and strong competition and for different frequencies of PDV epidemics. Results show that the harbour seals are resilient to competition while exerting a negative effect on grey seal abundance under moderate to strong competition. Hence Baltic grey seal benefit from weaker levels of competition. Under moderate and strong competition grey seal abundance is a direct function of the PDV frequency as this reduces the competitive strength of harbour seals. Theoretically this means that higher frequencies of PDV or other pathogens epidemics could facilitate an expansion of Baltic grey seal into Kattegat-Skagerrak. Independent of interaction strength and frequency of epidemics the projected changes to abundances are slow (50-100 years), and even in exceedingly stable

  7. Pure commercial gold foils as neutron flux monitor: Neutron self-shielding assessment

    International Nuclear Information System (INIS)

    Haddad, Kh.; Haj-Hassan, H.; Helal, W.

    2007-01-01

    An assessment of pure commercial (99.9%) gold foils as neutron flux monitor was performed. A thin foils of pure commercial gold were prepared as an in-house reference material for neutron flux measurement. The assessed foils are available commercially and its cost is much less than the certified ones. Determination of the neutron self-shielding factors in these foils for both thermal and epithermal neutrons have been done experimentally. These foils show good results repeatability and good agreement with certified activation monitors. According to the well-known physical constants of the nuclide and its low cost comparing with certified foils, it can be used as an in-house reference monitor

  8. Development of Gating Foils To Inhibit Ion Feedback Using FPC Production Techniques

    Science.gov (United States)

    Arai, D.; Ikematsu, K.; Sugiyama, A.; Iwamura, M.; Koto, A.; Katsuki, K.; Fujii, K.; Matsuda, T.

    2018-02-01

    Positive ion feedback from a gas amplification device to the drift region of the Time Projection Chamber for the ILC can deteriorate the position resolution. In order to inhibit the feedback ions, MPGD-based gating foils having good electron transmission have been developed to be used instead of the conventional wire gate. The gating foil needs to control the electric field locally in opening or closing the gate. The gating foil with a GEM (gas electron multiplier)-like structure has larger holes and smaller thickness than standard GEMs for gas amplification. It is known that the foil transmits over 80 % of electrons and blocks ions almost completely. We have developed the gating foils using flexible printed circuit (FPC) production techniques including an improved single-mask process. In this paper, we report on the production technique of 335 μm pitch, 12.5 μm thick gating foil with 80 % transmittance of electrons in ILC conditions.

  9. Control of Oscillating Foil for Propulsion of Biorobotic Autonomous Underwater Vehicle (AUV

    Directory of Open Access Journals (Sweden)

    S. N. Singh

    2005-01-01

    Full Text Available The paper treats the question of control of a laterally and rotationally oscillating hydrofoil for the propulsion of biologically inspired robotic (biorobotic autonomous underwater vehicles (BAUVs. Sinusoidal oscillations of foils produce maneuvering and propulsive forces. The design is based on the internal model principle. Two springs are used to transmit forces from the actuators to the foil. Oscillating fins produce periodic forces, which can be used for fish-like propulsion and control of autonomous underwater vehicles (AUVs. The equations of motion of the foil include hydrodynamic lift and moment based on linear, unsteady, aerodynamic theory. A control law is derived for the lateral and rotational sinusoidal oscillation of the foil. In the closed-loop system, the lateral displacement and the rotational angle of the foil asymptotically follow sinusoidal trajectories of distinct frequencies and amplitudes independently. Simulation results are presented to show the trajectory tracking performance of the foil for different freestream velocities and sinusoidal command trajectories.

  10. The stripping foil test stand in the Linac4 transfer line

    CERN Document Server

    Weterings, W; Noulibos, R; Sillanoli, Y; van Trappen, P

    2015-01-01

    The 160 MeV H− beam from the Linac4 (L4) linear accelerator at CERN will be injected into the proton synchrotron booster (PSB) with a new H− charge-exchange injection system. It will include a stripping foil, to convert H− into protons by stripping off the electrons. To gain experience with these very fragile foils, prior to the installation in the PSB, and test different foil materials and thicknesses, lifetimes of the foils, the foil changing mechanism and interlocking functions, a stripping foil test stand will be installed in the L4 transfer line in 2015. This paper describes the mechanical design of the system and discusses the test possibilities and parameters.

  11. The stripping foil test stand in the Linac4 transfer line

    International Nuclear Information System (INIS)

    Weterings, W.; Bracco, C.; Noulibos, R.; Sillanoli, Y.; Trappen van, P.

    2015-01-01

    The 160 MeV H - beam from the Linac4 (L4) linear accelerator at CERN will be injected into the proton synchrotron booster (PSB) with a new H - charge-exchange injection system. It will include a stripping foil, to convert H - into protons by stripping off the electrons. To gain experience with these very fragile foils, prior to the installation in the PSB, and test different foil materials and thicknesses, lifetimes of the foils, the foil changing mechanism and interlocking functions, a stripping foil test stand will be installed in the L4 transfer line in 2015. This paper describes the mechanical design of the system and discusses the test possibilities and parameters. (author)

  12. Core disruptive accident margin seal

    International Nuclear Information System (INIS)

    Garin, J.; Belsick, J.C.

    1978-01-01

    Disclosed is an apparatus for sealing the annulus defined between a substantially cylindrical rotatable first riser assembly and plug combination disposed in a substantially cylindrical second riser assembly and plug combination of a nuclear reactor system. The apparatus comprises a flexible member disposed between the first and second riser components and attached to a metal member which is attached to an actuating mechanism. When the actuating mechanism is not actuated, the flexible member does not contact the riser components thus allowing the free rotation of the riser components. When desired, the actuating mechanism causes the flexible member to contact the first and second riser components in a manner to block the annulus defined between the riser components, thereby sealing the annulus between the riser components

  13. Transport of multiassembly sealed canisters

    International Nuclear Information System (INIS)

    Quinn, R.D.; Lehnert, R.A.; Rosa, J.M.

    1992-01-01

    A significant portion of the commercial spent nuclear fuel in dry storage in the US will be stored in multiassembly sealed canisters before the DOE begins accepting fuel from utilities in 1998. This paper reports that it is desirable from economic and ALARA perspectives to transfer these canisters directly from the plant to the MRS. To this end, it is necessary that the multiassembly sealed canisters, which have been licensed for storage under 10CFR72, be qualified for shipment within a suitable shipping cask under the rules of 10CFR71. Preliminary work performed to date indicates that it is feasible to license a current canister design for transportation, and work is proceeding on obtaining NRC approval

  14. Seal for fluid forming tools

    Science.gov (United States)

    Golovashchenko, Sergey Fedorovich [Beverly Hills, MI; Bonnen, John Joseph Francis [Milford, MI

    2012-03-20

    An electro-hydraulic forming tool for forming a sheet metal blank in a one-sided die has first and second rigid rings that engage opposite sides of a sheet metal blank. The rigid rings are contained within slots on a die portion and a hydraulic force applicator portion of the forming tool. The seals are either resiliently biased by an elastomeric member or inherently resiliently biased into contact with the blank.

  15. Transmission of Fast Highly Charged Ions through a Single Glass Macrocapillary and Polycarbonate Nanocapillary Foils

    Science.gov (United States)

    Ayyad, A. M.; Dassanayake, B. S.; Keerthisinghe, D.; DeSilva, G. G.; Elkafrawy, T.; Kayani, N.; Tanis, J. A.

    2012-11-01

    Transmission of 3 MeV protons and 16 MeV O5+ ions through a single glass macrocapillary and a polycarbonate nanocapillary foil has been investigated. Results show that 3 MeV protons transmit through the capillary and the foils with little or no energy loss, while 16 MeV O5+ ions show transmission through the capillary and the foil with energy losses that vary with the tilt angle, and there are also changes in the charge state.

  16. X-Ray Measurements Of Total Reflectivity And Scattering From Au-Coated Foils

    DEFF Research Database (Denmark)

    Hornstrup, Allan; Christensen, Finn Erland; Schnopper, H. W.

    1989-01-01

    We present X-ray measurements of total reflectivity and scattering from gold coated foils. The foils are two sorts of 0.3 mm thick dip-lacquered aluminum, 0.125 mm thick plastic (Upilex) and 0.5 mm thick dip-lacquered nickel. The analysis of the data show a high reflectivity for all but the plastic...... foil, and only small microroughness (-10A at lengthscales below -0.1 micron), evidenced by low resolution scat-tering measurements....

  17. Beam-foil-gas spectroscopy - A technique for studying steady-state non-equilibrium processes.

    Science.gov (United States)

    Bickel, W. S.; Veje, E.; Carriveau, G.; Anderson, N.

    1971-01-01

    When a thin foil is inserted in the beam of a beam-gas experiment, the beam particle state populations are driven far from their beam-gas equilibrium values. Downstream from the foil, the 'new beam' and gas species interact to produce a new equilibrium, usually different from the beam-gas equilibrium. Experimental results are presented to demonstrate this effect and to show how relative cross-section measurements can be used to study the beam-foil interaction.

  18. Stripping Foil Issues for H- Injection into the CERN PSB at 160 MeV

    CERN Document Server

    Goddard, B; Bracco, C; Carli, C; Meddahi, M; Weterings, W J M

    2010-01-01

    Beam physics considerations for the stripping foil of the 160 MeV PSB H- injection systems are described, including the arguments for the foil type, thickness, geometry and positioning. The foil performance considerations are described, including expected stripping efficiency, emittance growth, energy straggling, temperature and lifetime. The different beam loss mechanisms are quantified in the context of the aperture limits, operational considerations and collimation requirements.

  19. Experimental and theoretical analysis of a rigid rotor supported by air foil bearings

    DEFF Research Database (Denmark)

    Larsen, Jon Steffen; Hansen, Asger J. T.; Santos, Ilmar

    2015-01-01

    The popularity of compressors utilizing foil bearings is increasing. Their mechanical design is challenging, and an accurate prediction of the bearing coefficients is important. A mathematical model taking into account the foil structure, and the detailed geometry of a three pad foil bearing are ...... for the first order equation. Calculated bearing coefficients are compared to experimental results obtained from a dedicated test rig. Generally, good agreement is observed and minor discrepancies for the damping coefficients are discussed....

  20. Steam Turbine Flow Path Seals (a Review)

    Science.gov (United States)

    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

  1. Analysis of Cartilage-Polydioxanone Foil Composite Grafts

    Science.gov (United States)

    Kim, James H.; Wong, Brian

    2014-01-01

    This study presents an analytical investigation into the mechanical behavior of a cartilage-polydioxanone (PDS) plate composite grafts. Numerical methods are used to provide a first-order, numerical model of the flexural stiffness of a cartilage-PDS graft. Flexural stiffness is a measure of resistance to bending and is inversely related to the amount of deformation a structure may experience when subjected to bending forces. The cartilage-PDS graft was modeled as a single composite beam. Using Bernoulli-Euler beam theory, a closed form equation for the theoretical flexural stiffness of the composite graft was developed. A parametric analysis was performed to see how the flexural properties of the composite model changed with varying thicknesses of PDS foil. The stiffness of the cartilage-PDS composite using 0.15-mm-thick PDS was four times higher than cartilage alone. The composite with a 0.5-mm-thick PDS graft was only 1.7 times stiffer than the composite with the 0.15-mm-thick PDS graft. Although a thicker graft material will yield higher flexural stiffness for the composite, the relationship between composite stiffness and PDS thickness is nonlinear. After a critical point, increments in graft thickness produce gradually smaller improvements in flexural stiffness. The small increase in stiffness when using the thicker PDS foils versus the 0.15 mm PDS foil may not be worth the potential complications (prolonged foreign body reaction, reduction in nutrient diffusion to cartilage) of using thicker artificial grafts. PMID:24327249

  2. Large-area monolayer hexagonal boron nitride on Pt foil.

    Science.gov (United States)

    Park, Ji-Hoon; Park, Jin Cheol; Yun, Seok Joon; Kim, Hyun; Luong, Dinh Hoa; Kim, Soo Min; Choi, Soo Ho; Yang, Woochul; Kong, Jing; Kim, Ki Kang; Lee, Young Hee

    2014-08-26

    Hexagonal boron nitride (h-BN) has recently been in the spotlight due to its numerous applications including its being an ideal substrate for two-dimensional electronics, a tunneling material for vertical tunneling devices, and a growth template for heterostructures. However, to obtain a large area of h-BN film while maintaining uniform thickness is still challenging and has not been realized. Here, we report the systematical study of h-BN growth on Pt foil by using low pressure chemical vapor deposition with a borazine source. The monolayer h-BN film was obtained over the whole Pt foil (2 × 5 cm(2)) under foil size. A borazine source was catalytically decomposed on the Pt surface, leading to the self-limiting growth of the monolayer without the associating precipitation, which is very similar to the growth of graphene on Cu. The orientation of the h-BN domains was largely confined by the Pt domain, which is confirmed by polarizing optical microscopy (POM) assisted by the nematic liquid crystal (LC) film. The total pressure and orientation of the Pt lattice plane are crucial parameters for thickness control. At high pressure (∼0.5 Torr), thick film was grown on Pt (111), and in contrast, thin film was grown on Pt (001). Our advances in monolayer h-BN growth will play an important role to further develop a high quality h-BN film that can be used for vertical tunneling, optoelectronic devices and growth templates for a variety of heterostructures.

  3. Corrections in the gold foil activation method for determination of neutron beam density

    DEFF Research Database (Denmark)

    Als-Nielsen, Jens Aage

    1967-01-01

    A finite foil thickness and deviation in the cross section from the 1ν law imply corrections in the determination of neutron beam densities by means of foil activation. These corrections, which depend on the neutron velocity distribution, have been examined in general and are given in a specific...... example for a reactor beam transmitted through a 30 cm Bi filter. The effective cross section differs 0.5% from the capture cross section at 2200 m/s. For a 20 mg/cm2 Au foil the correction for beam attenuation and hardening through the foil is 0.7% and the activity correction is 1.5%....

  4. Development progress of wide LEU foils for Mo-99 irradiation target at KAERI

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ki Hwan; Son, Myung Koon; Lee, Don Bae; Lee, Byung Chul; Kim, Chang Kyu [Korea Atomic Energy Research Institute , Taejon (Korea, Republic of)

    2005-07-01

    As the uranium foils for Mo-99 irradiation target, which are charged into a reactor, can be conventionally fabricated at laboratory scale, but not yet at a commercialized scale by a hot rolling method due to some problems in foil quality, productivity and economic efficiency, an attention has shifted to the development of new improved technology. Under these circumstances, an alternative fabrication method of U polycrystalline foils has been investigated using a cooling roll casting method, in order to produce a fission isotope {sup 99}Mo, the parent nuclide of {sup 99m}Tc. The fabrication method of wide LEU foils produced by a coolingroll casting was recently developed to improve the quality of the uranium foils and the economic efficiency of the foil fabrication with modifications of the casting apparatus and adjustments of the process parameters. A continuous polycrystalline LEU foil with a thickness range of 100 to 150{mu}m and a width of about 50 mm, exceeding 5m in length for a batch procedure, could be fabricated with a better quality of the uranium foil and a higher yield of the foil fabrication, through improvements of the casting apparatus and variations of the process parameters.

  5. Development progress of wide LEU foils for Mo-99 irradiation target at KAERI

    International Nuclear Information System (INIS)

    Kim, Ki Hwan; Son, Myung Koon; Lee, Don Bae; Lee, Byung Chul; Kim, Chang Kyu

    2005-01-01

    As the uranium foils for Mo-99 irradiation target, which are charged into a reactor, can be conventionally fabricated at laboratory scale, but not yet at a commercialized scale by a hot rolling method due to some problems in foil quality, productivity and economic efficiency, an attention has shifted to the development of new improved technology. Under these circumstances, an alternative fabrication method of U polycrystalline foils has been investigated using a cooling roll casting method, in order to produce a fission isotope 99 Mo, the parent nuclide of 99m Tc. The fabrication method of wide LEU foils produced by a coolingroll casting was recently developed to improve the quality of the uranium foils and the economic efficiency of the foil fabrication with modifications of the casting apparatus and adjustments of the process parameters. A continuous polycrystalline LEU foil with a thickness range of 100 to 150μm and a width of about 50 mm, exceeding 5m in length for a batch procedure, could be fabricated with a better quality of the uranium foil and a higher yield of the foil fabrication, through improvements of the casting apparatus and variations of the process parameters

  6. Design optimization of seal structure for sealing liquid by magnetic fluids

    International Nuclear Information System (INIS)

    Liu Tonggang; Cheng Yusheng; Yang Zhiyi

    2005-01-01

    The durability of the magnetic fluid seal clearly decreases when sealing another liquid because of the interface instability caused by the applied magnetic field and the velocity difference of the two liquids. With an intention to establish a stable interface during sealing liquid, a new magnetic fluid seal was developed in this paper. The parameters of the structure were optimized by a simulation apparatus. And the magnetic fluid seal designed based on the optimum parameters shows good performance and long life for sealing lubricating oil

  7. Foil system fatigue load environments for commercial hydrofoil operation

    Science.gov (United States)

    Graves, D. L.

    1979-01-01

    The hydrofoil fatigue loads environment in the open sea is examined. The random nature of wave orbital velocities, periods and heights plus boat heading, speed and control system design are considered in the assessment of structural fatigue requirements. Major nonlinear load events such as hull slamming and foil unwetting are included in the fatigue environment. Full scale rough water load tests, field experience plus analytical loads work on the model 929 Jetfoil commercial hydrofoil are discussed. The problem of developing an overall sea environment for design is defined. State of the art analytical approaches are examined.

  8. Critical mass experiment using U-235 foils and lucite plates

    International Nuclear Information System (INIS)

    Sanchez, R.; Butterfield, K.; Kimpland, R.; Jaegers, P.

    1998-01-01

    The main objective of this experiment was to show how the multiplication of the system increases as moderated material is placed between highly enriched uranium foils. In addition, this experiment served to demonstrate the hand-stacking techniques, and approach to criticality by remote operation. This experiment was designed by Tom McLaughlin in the mid seventies as part of the criticality safety course that is taught at Los Alamos Critical Experiment Facility (LACEF). The W-U-235 ratio for this experiment was 215 which is where the minimum critical mass for this configuration occurs

  9. Optical observations of molecular dissociation in thin foils

    International Nuclear Information System (INIS)

    Berry, H.G.; Gay, T.J.; Brooks, R.L.

    1981-01-01

    We have measured the intensity and polarizations of light emitted from atomic excited states of dissociated molecular ions. Using HeH + projectiles, we have observed factors of 1-5 enhancements of the light from n=3, sup(1,3)P,D states of He I and some He II and H I emissions. Observations of Lyman alpha emission after dissociation of H 2 + and H 3 + show rapid variations in light yield for small internuclear separations at the foil surface. (author)

  10. Prediction of Gas Lubricated Foil Journal Bearing Performance

    Science.gov (United States)

    Carpino, Marc; Talmage, Gita

    2003-01-01

    This report summarizes the progress in the first eight months of the project. The objectives of this research project are to theoretically predict the steady operating conditions and the rotor dynamic coefficients of gas foil journal bearings. The project is currently on or ahead of schedule with the development of a finite element code that predicts steady bearing performance characteristics such as film thickness, pressure, load, and drag. Graphical results for a typical bearing are presented in the report. Project plans for the next year are discussed.

  11. Measurement of neutron multiplication in Pb by Mn foils

    International Nuclear Information System (INIS)

    Chen Yuan; Liu Rong; Guo Haiping; Jiang Wenmian; Shen Jian

    1994-01-01

    The Leakage neutron multiplication in bulk lead has been measured using the total absorption detector and relative method. The polyethylene sphere of 138 cm in diameter is used as the moderator and total absorption detector. The measured results from 55 Mn foils and 6 Li glass are compared. The neutron multiplication is 1.74 with the lead shell of 23.1 cm thick. The measured result is consistent with the calculated one with ANISN code and ENDF/B-6 evaluated data within the experimental error. (4 figs., 3 tabs.)

  12. Implementation of multiple measures to improve reactor recirculation pump sealing performance in nuclear boiling water reactor service

    Energy Technology Data Exchange (ETDEWEB)

    Loenhout, Gerard van [Flowserve B.V., Etten-Leur (Netherlands). Nuclear Services and Solutions Engineering; Hurni, Juerg

    2015-05-15

    A modern reactor recirculation pump circulates a large volume of high temperature, very pure water from the reactor pressure vessel back to the core by feeding into multiple stationary jet pumps inside the vessel. Together with the jet pumps, they allow station operators to vary coolant flow and variable pump speed provides the best and most stable reactor power control. A crucial technical problem with a recirculation pump, such as a mechanical seal indicating loss of sealing pressure, may result in a power station having to shut down for repair. This article describes the sudden increase in stray current phenomenon leading to rapid and severe deterioration of the mechanical end face shaft seal in a reactor recirculation pump. This occurred after the installation of a variable frequency converter replacing the original motor-generator set. This article will also discuss the 2,500 hour laboratory test results conducted under reactor recirculation pump sealing conditions using a newly developed seal face technology recently implemented to overcome challenges when sealing neutral, ultra-pure water. In addition, the article will describe the elaborate shaft grounding arrangement and the preliminary measurement results achieved in order to eliminate potential damages to both pump and mechanical seal.

  13. Implementation of multiple measures to improve reactor recirculation pump sealing performance in nuclear boiling water reactor service

    Energy Technology Data Exchange (ETDEWEB)

    Loenhout, Gerard van [Flowserve B.V., Etten-Leur (Netherlands). Nuclear Services and Solutions Engineering; Hurni, Juerg

    2014-07-01

    A modern reactor recirculation pump circulates a large volume of high temperature, very pure water from the reactor pressure vessel back to the core. A crucial technical problem with a recirculation pump, such as a mechanical seal indicating loss of sealing pressure, may result in a power station having to shut down for repair. The paper describes the sudden increase in stray current phenomenon leading to rapid and severe deterioration of the mechanical end face shaft seal in a reactor recirculation pump. This occurred after the installation of a variable frequency converter replacing the original motorgenerator set.

  14. Implementation of multiple measures to improve reactor recirculation pump sealing performance in nuclear boiling water reactor service

    International Nuclear Information System (INIS)

    Loenhout, Gerard van; Hurni, Juerg

    2014-01-01

    A modern reactor recirculation pump circulates a large volume of high temperature, very pure water from the reactor pressure vessel back to the core. A crucial technical problem with a recirculation pump, such as a mechanical seal indicating loss of sealing pressure, may result in a power station having to shut down for repair. The paper describes the sudden increase in stray current phenomenon leading to rapid and severe deterioration of the mechanical end face shaft seal in a reactor recirculation pump. This occurred after the installation of a variable frequency converter replacing the original motorgenerator set.

  15. Vacuum sealing with a spiral grooved gas dynamic seal

    International Nuclear Information System (INIS)

    Sawada, Tadashi

    1979-01-01

    Gas dynamic seals with rectangular spiral grooves are studied theoretically taking the effects of sidewalls of the grooves and the effects of gas compressibility into account, and slip boundary conditions are employed. The results are compared with the existing experimental data and the validity of the theory is confirmed over a wide pressure range except for the extremely low pressures. Suggestions are made regarding the choice of the geometrical dimensions, i.e., aspect ratio, helix angle, clearance parameter and groove width ratio. (author)

  16. Seal analysis technology for reactor pressure vessel

    International Nuclear Information System (INIS)

    Zheng Liangang; Zhang Liping; Yang Yu; Zang Fenggang

    2009-01-01

    There is the coolant with radiation, high temperature and high pressure in the reactor pressure vessel (RPV). It is closely correlated to RPV sealing capability whether the whole nuclear system work well or not. The aim of this paper is to study the seal analysis method and technology, such as the pre-tensioning of the bolt, elastoplastic contact and coupled technology of thermal and structure. The 3 D elastoplastic seal analysis method really and generally consider the loads and model the contact problem with friction between the contact plates. This method is easier than the specialized seal program and used widely. And it is more really than the 2 D seal analysis method. This 3 D elastoplastic seal analysis method has been successfully used in the design and analysis of RPV. (authors)

  17. Guide to optimized replacement of equipment seals

    International Nuclear Information System (INIS)

    Gleason, J.F.

    1990-03-01

    A reevaluation of current scheduled replacement intervals of polymeric seals in plant equipment can achieve significant benefits. Information is provided which has the potential for increasing replacement intervals based on better information on how seals have performed through unique nuclear industry tests to qualify equipment, improved elastomers and increased knowledge of the failure mechanisms and related performance. The research was performed by reviewing applications of elastomeric seals in nuclear plants and practice associated with defining seal replacement intervals in the nuclear power and other industries. Performance indicators and how they predict degradation of seals were evaluated. Guidelines and a flow chart for reevaluating seal replacement intervals are provided. 29 refs., 38 figs., 8 tabs

  18. Kinetics of the oxidation of Zn foils in air atmosphere

    Energy Technology Data Exchange (ETDEWEB)

    Baca, R; Martinez, J [Centro de Investigacion de Dispositivos Semiconductores, BUAP, Puebla. C.P. 72570 (Mexico); Kryshtab, T [Departamento de Ciencias de Materiales, ESFM - IPN, Mexico D.F (Mexico); Juarez, G; Solache, H; Andraca, J; Garcia, O; Pena-Sierra, R, E-mail: rbaca02006@yahoo.com.mx

    2010-02-15

    The formation kinetics of ZnO thin films grown by oxidation of polycrystalline Zn foils in air atmosphere at temperatures below the melting point is reported. Previous to the oxidation process the Zn foils were polished to produce mirror-like finished surfaces. The growth rate of the ZnO films was monitored by ellipsometric measurements. The growth rate of the ZnO films under 100 nm follows a linear and parabolic behavior in accordance with previously reported studies. The thicknesses of the films strongly influence the appearance of the final produced ZnO surface. The ZnO films surfaces with thicknesses less than 100 nm resulted uniform with low rms roughness. However as the films become thicker the rms roughness increased and a uniform distribution of whiskers was observed. X-ray diffraction and photoluminescence (PL) studies were done on the ZnO films to find out their structural and optical characteristics. PL spectra on the films are composed by two main bands; a weak near-band gap in the ultraviolet region and a strong but well defined green band. A discussion is included on the origins of the observed PL spectra.

  19. Modelling Accumulator Stripper Foil Heating for ESSNUSB Facility

    CERN Document Server

    Martini, Michel

    2015-01-01

    It is proposed to use the 2.0 GeV, 5 MW proton linac, 2.86 ms long pulses at 14 Hz of the European Spallation Source [1], [2] being built in Lund, Sweden to deliver, alternately with the spallation neutron production a very intense neutrino beam to enable the discovery of leptonic CP violation. To this end the linac would be upgraded to supply, in addition to the 2.86 ms long proton pulses at 14 Hz, four 0.72 ms H short pulses at 70 Hz for neutrino production. Because of the high current required in the pulsed neutrino horn, the length of the pulses used for neutrino production will need to be compressed to a few s with the aid of an accumulator ring. Charge exchange injection of an H- beam from the linac will be used, the linac delivering 1.1E15 H- per pulse. This paper is about stripping foil heating considerations, emphasizing the detailed evaluation of the foil temperature over the multiple ring re-fills

  20. Effect of defence response time during lunge in foil fencing.

    Science.gov (United States)

    Gutiérrez-Cruz, Carmen; Rojas, F Javier; Gutiérrez-Davila, Marcos

    2016-01-01

    The aim of this study was to analyse the effect of stimulus change timing on reaction response time parameters, horizontal velocity of the centre of mass (CM) and precision during offensive actions in fencing. Twelve fencers from the Spanish National Foil Team were included in the study. Two 500 Hz force plates were used to register the horizontal component of the reaction force while a 3D video camera set at 250 Hz recorded the spatial position of 11 body markers and a projector connected to a programmed stopwatch projected a moving target (stimulus) on a screen. When the circle (target) appeared in the centre of the plastron, fencers had to execute a step-forward-lunge as fast as possible, trying to touch the circle with the tip of the foil. During the lunge, the position of the target could randomly shift or not to three different positions. The stimulus change was performed randomly at four different times with a progressive delay. The results show that target changes did not have any effect when they occurred at the beginning of the movement sequence. However, when the target change was delayed, reaction and movement times increased and the technical execution of the lunge changed, leading to more errors.

  1. Pengaruh Posisi Foil Terhadap Gaya Angkat Dan Hambatan Kapal Katamaran

    Directory of Open Access Journals (Sweden)

    Muhammad Rizki Darmawan Adi Kusuma

    2017-08-01

    Full Text Available Perkembangan teknologi dalam dunia perkapalan terjadi sangat pesat, mulanya kapal memiliki satu lambung (monohull, kemudian berkembang dengan munculnya kapal katamaran atau memiliki dua lambung, kapal katamaran memiliki banyak kelebihan dibanding dengan monohull mulai dari segi hambatan, olah gerak, dan lain-lain. Kapal katamaran akhirnya dikembangkan lagi dengan menjadikannya kapal hydrofoil yang bertujuan untuk mengurangi hambatan. Hydrofoil adalah sebuah kapal dengan bagian seperti sayap yang dipasang pada penyangga di bawah lambung kapal yang digunakan untuk mengangkat lambung kapal, pada saat kapal mencapai kecepatan tinggi yang menyebabkan pengurangan hambatan. Pada penelitian ini bertujuan untuk mendapatkan konfigurasi posisi foil yang menghasilkan gaya angkat paling besar serta hambatan yang paling kecil. Dalam melaksanakan penelitian ini penulis menggunakan program komputer berbasis Computational Fluid Dynamic(CFD untuk penyelesaian masalah dari tujuan penelitian, Computational fluid dynamic(CFD merupakan ilmu sains dalam penentuan penyelesaian numerik dinamika fluida.Penelitian dilakukan dengan cara menganalisa dan menghitung hambatan total kapal menggunakan model.Berdasarkan hasil analisa menggunakan software Tdyn 12.2.3.0 didapatkan nilai hambatan untuk berbagai variasi konfigurasi foil. Nilai hambatan total dapat diperkecil  hingga 37,56%, nilai ini terjadi pada Froude Number 1,737 pada variasi konfigurasi Canard dengan konfigurasi 65%(aft dan 35%(fore.

  2. System requirements for the Los Alamos foil-implosion project

    International Nuclear Information System (INIS)

    Brownell, J.; Bowers, R.; Greene, A.; Lindemuth, I.; Nickel, G.; Oliphant, T.; Weiss, D.

    1983-01-01

    The goal of the Los Alamos imploding foil project is the development of an intense source of soft x rays and hot plasma produced from the thermalization of 1 to 10 MJ of plasma kinetic energy. The source will be used for material studies and fusion experiments. Specifically, thin, current-carrying cylindrical metallic plasmas are imploded via their self-magnetic forces. Features of this project are the use of high-explosive-driven flux-compression generators as the prime power source to achieve very high energies and fast opening switches to shorten the electrical pulses. To reach a load kinetic energy of 10 MJ, it is expected that the foil-plasma must carry about 50 MA of current and must implode in less than 1/2 μsec. This imposes the requirements that switch opening times must be less than 1/2 μsec and the transmission line must withstand voltages of about 1 MV. The system being pursued at Los Alamos is described, and model calculations are presented

  3. Kinetics of the oxidation of Zn foils in air atmosphere

    Science.gov (United States)

    Baca, R.; Juárez, G.; Solache, H.; Andraca, J.; Martinez, J.; Garcia, O.; Kryshtab, T.; Peña-Sierra, R.

    2010-02-01

    The formation kinetics of ZnO thin films grown by oxidation of polycrystalline Zn foils in air atmosphere at temperatures below the melting point is reported. Previous to the oxidation process the Zn foils were polished to produce mirror-like finished surfaces. The growth rate of the ZnO films was monitored by ellipsometric measurements. The growth rate of the ZnO films under 100 nm follows a linear and parabolic behavior in accordance with previously reported studies. The thicknesses of the films strongly influence the appearance of the final produced ZnO surface. The ZnO films surfaces with thicknesses less than 100 nm resulted uniform with low rms roughness. However as the films become thicker the rms roughness increased and a uniform distribution of whiskers was observed. X-ray diffraction and photoluminescence (PL) studies were done on the ZnO films to find out their structural and optical characteristics. PL spectra on the films are composed by two main bands; a weak near-band gap in the ultraviolet region and a strong but well defined green band. A discussion is included on the origins of the observed PL spectra.

  4. Monte Carlo transport of electrons and positrons through thin foils

    International Nuclear Information System (INIS)

    Legarda, F.; Idoeta, R.

    2000-01-01

    In the different measurements made with electrons traversing matter it becomes useful the knowledge of its transmission through that medium, their paths and their angular distribution through matter so as to process and get information about the traversed medium and to improve and innovate the techniques that employ electrons, as medical applications or materials irradiation. This work presents a simulation of the transport of beams of electrons and positrons through thin foils using an analog Monte Carlo code that simulates in a detailed way every electron movement or interaction in matter. As those particles penetrate thin absorbers it has been assumed that they interact with matter only through elastic scattering, with negligible energy loss. This type of interaction has been described quite precisely because its angular form influences very much the angular distribution of electrons and positrons in matter. With this code it has been calculated the number of particles, with energies between 100 and 3000 keV, that are transmitted through different media of various thicknesses as well as its angular distribution, showing a good agreement with experimental data. The discrepancies are less than 5% for thicknesses lower than about 30% of the corresponding range in the tested material. As elastic scattering is very anisotropic, angular distributions resemble a collimated incident beam for very thin foils becoming slowly more isotropic when absorber thickness is increased. (author)

  5. The thermal and mechanical deformation study of up-stream pumping mechanical seal

    International Nuclear Information System (INIS)

    Chen, H L; Xu, C; Zuo, M Z; Wu, Q B

    2015-01-01

    Taking the viscosity-temperature relationship of the fluid film into consideration, a 3-D numerical model was established by ANSYS software which can simulate the heat transfer between the upstream pumping mechanical seal stationary and rotational rings and the fluid film between them as well as simulate the thermal deformation, structure deformation and the coupling deformation of them. According to the calculation result, thermal deformation causes the seal face expansion and the maximum thermal deformation appears at the inside of the seal ring. Pressure results in a mechanical deformation, the maximum deformation occurs at the top of the spiral groove and the overall trend is inward the mating face, opposite to the thermal deformation. The coupling deformation indicate that the thermal deformation can be partly counteracted by pressure deformation. Using this model, the relationship between deformation and shaft speed and the sealing liquid pressure was studied. It's found that the shaft speed will both enhance the thermal and structure deformation and the fluid pressure will enhance the structure deformation but has little to do with the thermal deformation. By changing the sealing material, it's found that material with low thermal expansion coefficient and low elastic modulus will suffer less thermal-pressure deformation

  6. Study on AE in Mechanical Seal Lift-off Recognition of Mechanical Main Shaft

    Directory of Open Access Journals (Sweden)

    Erqing Zhang

    2014-06-01

    Full Text Available For the problem of the determination of lift-off position and the measurement of end face thickness for mechanical seal more difficult, the method based on acoustic emission signal end face lift-off condition monitoring technology for mechanical seal was proposed. The electric eddy current sensor made direct measurement in the internal of mechanical seal device, and the acoustic emission sensor was fixed in the outside for indirect measurement. The acoustic emission signals were de-noised by wavelet threshold de-noising method. The representative energy features were selected by wavelet packet energy spectrum algorithm. It was established that the Radial Basis Function neural network model used for identification of the mechanical seal lift-off position, and the extracted wavelet energy features as its input. It was confirmed accurate and effective that the acoustic emission identification technology through comparing with the data detected by electric eddy current sensor. So using the acoustic emission technology realized the identification of the mechanical seal lift-off position of mechanical main shaft from inside to outside. It is convenient to be used and promotion in industrial field.

  7. The thermal and mechanical deformation study of up-stream pumping mechanical seal

    Science.gov (United States)

    Chen, H. L.; Xu, C.; Zuo, M. Z.; Wu, Q. B.

    2015-01-01

    Taking the viscosity-temperature relationship of the fluid film into consideration, a 3-D numerical model was established by ANSYS software which can simulate the heat transfer between the upstream pumping mechanical seal stationary and rotational rings and the fluid film between them as well as simulate the thermal deformation, structure deformation and the coupling deformation of them. According to the calculation result, thermal deformation causes the seal face expansion and the maximum thermal deformation appears at the inside of the seal ring. Pressure results in a mechanical deformation, the maximum deformation occurs at the top of the spiral groove and the overall trend is inward the mating face, opposite to the thermal deformation. The coupling deformation indicate that the thermal deformation can be partly counteracted by pressure deformation. Using this model, the relationship between deformation and shaft speed and the sealing liquid pressure was studied. It's found that the shaft speed will both enhance the thermal and structure deformation and the fluid pressure will enhance the structure deformation but has little to do with the thermal deformation. By changing the sealing material, it's found that material with low thermal expansion coefficient and low elastic modulus will suffer less thermal-pressure deformation.

  8. A seal analyzer for testing container integrity

    International Nuclear Information System (INIS)

    McDaniel, P.; Jenkins, C.

    1988-01-01

    This paper reports on the development of laboratory and production seal analyzer that offers a rapid, nondestructive method of assuring the seal integrity of virtually any type of single or double sealed container. The system can test a broad range of metal cans, drums and trays, membrane-lidded vessels, flexible pouches, aerosol containers, and glass or metal containers with twist-top lids that are used in the chemical/pesticide (hazardous materials/waste), beverage, food, medical and pharmaceutical industries

  9. Three-Dimensional Simulations of Flat-Foil Laser-Imprint Experiments at the National Ignition Facility

    Science.gov (United States)

    Shvydky, A.; Radha, P. B.; Rosenberg, M. J.; Anderson, K. S.; Goncharov, V. N.; Marozas, J. A.; Marshall, F. J.; McKenty, P. W.; Regan, S. P.; Sangster, T. C.; Hohenberger, M.; di Nicola, J. M.; Koning, J. M.; Marinak, M. M.; Masse, L.; Karasik, M.

    2017-10-01

    Control of shell nonuniformities imprinted by the laser and amplified by hydrodynamic instabilities in the imploding target is critical for the success of direct-drive ignition at the National Ignition Facility (NIF). To measure a level of imprint and its reduction by the NIF smoothing by spectral dispersion (SSD), we performed experiments that employed flat CH foils driven with a single NIF beam with either no SSD or the NIF indirect-drive SSD applied to the laser pulse. Face-on x-ray radiography was used to measure optical depth variations, from which the amplitudes of the foil areal-density modulations were obtained. Results of 3-D, radiation-hydrodynamic code HYDRA simulations of the growth of the imprint-seeded perturbations are presented and compared with the experimental data. This work was supported by the U.S. Department of Energy National Nuclear Security Administration under Award Number DE-NA0001944 and under the auspices of the Lawrence Livermore National Security, LLC, (LLNS) under Contract Number DE-AC52-07NA27344.

  10. Persistent organic pollutants (POPs) in Caspian seals of unusual mortality event during 2000 and 2001

    Energy Technology Data Exchange (ETDEWEB)

    Kajiwara, Natsuko [Center for Marine Environmental Studies, Ehime University, 2-5 Bunkyo-cho, Matsuyama 790-8577 (Japan)], E-mail: kajiwara.natsuko@nies.go.jp; Watanabe, Mafumi [Center for Marine Environmental Studies, Ehime University, 2-5 Bunkyo-cho, Matsuyama 790-8577 (Japan); Wilson, Susan [Tara Seal Research Centre, Co. Down, Northern Ireland (United Kingdom); Eybatov, Tariel [Geological Institute of the Azerbaijan Republic Academy of Science, Baku (Azerbaijan); Mitrofanov, Igor V. [Laboratory of Hydrobiology and Ecotoxicology, Institution of Zoology, Academgorodok, Almaty 480060 (Kazakhstan); Aubrey, David G. [Woods Hole Oceanographic Institution, Woods Hole, MA 02543 (United States); Khuraskin, Lev S. [Caspian Fisheries Research Institute, Astrakhan 414056 (Russian Federation); Miyazaki, Nobuyuki [Center for International Cooperation, Ocean Research Institute, The University of Tokyo, 1-15-1 Minamidai, Nakano-ku, Tokyo 164-8639 (Japan); Tanabe, Shinsuke [Center for Marine Environmental Studies, Ehime University, 2-5 Bunkyo-cho, Matsuyama 790-8577 (Japan)

    2008-03-15

    Persistent organic pollutants including organochlorine pesticides, PCBs, and PCDDs/DFs were determined in the blubber of Caspian seals, which died during an outbreak of canine distemper virus in 2000 and 2001. DDTs were the predominant contaminants that ranged from 3.1 to 560 {mu}g/g lipid. A negative correlation was observed between concentration of contaminants and blubber thickness. During spring, as the blubber layer becomes thin after breeding and moulting, seals may face higher risk due to the increased concentration of organochlorines in their bodies. TEQs in the blubber of Caspian seals (10-340 pg TEQ/g) were lower than those in seals from other locations, suggesting that toxic effects of these contaminants are a deal less in the present population and they are unlikely to be linked to mass mortality. The levels of PCBs and pesticides in Caspian seals, however, comparable to those in other aquatic mammals that have suffered from epizootics, might pose a risk of immunosuppression. - POPs in seals are high enough to induce immunosuppression.

  11. Modeling the effect of seal leakage on spontaneous heating in a longwall gob area

    Energy Technology Data Exchange (ETDEWEB)

    Smith, A.C.; Yuan, L. [National Inst. for Occupational Safety and Health, Pittsburgh, PA (United States). Office of Mine Safety and Health Research

    2010-07-01

    Three coal mines in the United States with a history of spontaneous combustion use a bleederless ventilation system as a control measure. In a bleederless system, one of the headgate entries is used as the tailgate entry of the succeeding panel and is isolated from the gob of the active panel by gob seals that are installed in the headgate entry as the face advances. An active longwall panel using a Y-type bleederless ventilation system was simulated in this study. As longwall mining progresses, some seals are known to leak. Computational fluid dynamics (CFD) simulations were performed to study the effect of seal leakage on spontaneous heating of coal in the longwall gob area. The simulation results showed that under typical bleederless ventilation conditions, the maximum temperature in the gob increased with an increase in leakage rate. The maximum temperature occurred at the headgate side corner at the back end of the panel. When only 1 or 2 seals were leaking, the maximum temperature occurred around the seal. The results demonstrate that complex interactions between pressure differential and gob permeability at different locations in the gob cause ventilation pathways. The interactions depend greatly on gob permeability and seal leakage rates. 8 refs., 1 tab., 14 figs.

  12. Research on performance of upstream pumping mechanical seal with different deep spiral groove

    International Nuclear Information System (INIS)

    Wang, Q; Chen, H L; Liu, T; Liu, Y H; Liu, Z B; Liu, D H

    2012-01-01

    As one new type of mechanical seal, Upstream Pumping Mechanical Seal has been widely used in fluid machinery. In this paper, structure of spiral groove is innovatively optimized to improve performance of Upstream Pumping Mechanical Seal with Spiral Groove: keeping the dam zone and the weir zone not changed, changing the bottom shape of spiral groove only, substituting different deep spiral groove for equal deep spiral groove. The simulation on Upstream Pumping Mechanical Seal with different deep spiral grooves is done using FVM method. According to calculation, the performances of opening force and pressure distribution on seals face are obtained. Five types of spiral grooves are analyzed, namely equal deep spiral groove, circumferential convergent ladder-like different deep spiral groove, circumferential divergent ladder-like different deep spiral groove, radial convergent ladder-like different deep spiral groove and radial divergent ladder-like different deep spiral groove. This paper works on twenty-five working conditions. The results indicate the performances of circumferential divergent 2-ladder different deep spiral groove are better than the others, with more opening force and better stabilization, while with the same leakage. The outcome provides theoretical support for application of Upstream Pumping Mechanical Seal with circumferential convergent ladder-like different deep spiral groove.

  13. Research on performance of upstream pumping mechanical seal with different deep spiral groove

    Science.gov (United States)

    Wang, Q.; Chen, H. L.; Liu, T.; Liu, Y. H.; Liu, Z. B.; Liu, D. H.

    2012-11-01

    As one new type of mechanical seal, Upstream Pumping Mechanical Seal has been widely used in fluid machinery. In this paper, structure of spiral groove is innovatively optimized to improve performance of Upstream Pumping Mechanical Seal with Spiral Groove: keeping the dam zone and the weir zone not changed, changing the bottom shape of spiral groove only, substituting different deep spiral groove for equal deep spiral groove. The simulation on Upstream Pumping Mechanical Seal with different deep spiral grooves is done using FVM method. According to calculation, the performances of opening force and pressure distribution on seals face are obtained. Five types of spiral grooves are analyzed, namely equal deep spiral groove, circumferential convergent ladder-like different deep spiral groove, circumferential divergent ladder-like different deep spiral groove, radial convergent ladder-like different deep spiral groove and radial divergent ladder-like different deep spiral groove. This paper works on twenty-five working conditions. The results indicate the performances of circumferential divergent 2-ladder different deep spiral groove are better than the others, with more opening force and better stabilization, while with the same leakage. The outcome provides theoretical support for application of Upstream Pumping Mechanical Seal with circumferential convergent ladder-like different deep spiral groove.

  14. Management of disused sealed sources

    International Nuclear Information System (INIS)

    Lukauskas, D.; Skridaila, N.

    2003-01-01

    The report presents the requirements on management of disused sealed sources in Lithuania; disused sealed source disposal facilities; performed safety analysis and planed repository safety improvements. The requirements on pre-disposal management of Disused Sealed Sources (DSS) are presented. The requirements on disposal of short lived VLLW and LILW (A, B and C classes) radioactive waste approved in 2002-2003. Generic Waste Acceptance Criteria for Near Surface Disposal, P-2003-01 approved in 2003. Requirements on disposal of Low and intermediate level long lived waste do not exist (D and E classes). Requirements for the disposal of disused sealed sources (F class) do not exist. Disposal method for the F class - Near Surface or Deep geological repository, depending on the waste acceptance criteria. Only one repository for institutional radioactive waste exist in Lithuania - Maisiagala repository. It is near surface RADON type disposal facility, built in 1963 and closed in 1988. It was constructed of the monolithic reinforced concrete with the dimensions 5 m x 15 m x 3 m, the thickness of the sidewalls is about 0.25 m and the thickness of the bottom is about 0.2 m. The overall volume is about 200 m 3 . At time of closure only three fifths of the volume had been filled. The empty two fifths of the vault were filled with concrete, then with sand, then with the concrete (0.01 m), hot bitumen and the 0.05 m asphalt layers. Monolithic concrete that was covered with bitumen and 0.05 m thick layer of asphalt closed the vault. Sand layer the thickness of which was not less than 1.2 m formed the cap. Disused radioactive sources embedded in a biological shielding were buried together with their shielding, the sources without the shielding were buried in two stainless steel containers. The total activity of buried radioactive nuclides is 3.42.10 -15 Bq (calculated according the documentation). There are some uncertainties about the inventory: from 1963 to 1973. After the

  15. Reusable tamper-indicating security seal

    International Nuclear Information System (INIS)

    Ryan, M.J.

    1981-01-01

    A reusable tamper-indicating mechanical security seal for use in safeguarding nuclear material has been developed. The high-security seal displays an unpredictable, randomly selected, five-digit code each time it is used. This five digit code serves the same purpose that the serial number does for conventional non-reusable seals - a unique identifier for each use or application. The newly developed reusable seal is completely enclosed within a seamless, tamper-indicating, plastic jacket. The jacket is designed to reveal any attempts to penetrate, section or to chemically remove and replace with a counterfeit for surreptitious purposes

  16. Seal for an object containing nuclear fuel

    International Nuclear Information System (INIS)

    Scheuerpflug, W.; Nentwich, D.

    1977-01-01

    This seal which cannot be counterfeited, specially for sealing nuclear objects, e.g. fuel rods, not only makes any damage which has taken place obvious, but makes identification according to a key possible. For this purpose a minimum number of 'particles' or small bodies, which are identical but of different permeability, are fixed inside a short tube during 'loading' of the seal in a certain or an accidental sequence. The sequence of the spheres, which represents a key, can only be determined by special electromagnetic measuring equipment. On first opening the seal, this key sequence is irrevocably destroyed. (HP) [de

  17. Ductile alloys for sealing modular component interfaces

    Energy Technology Data Exchange (ETDEWEB)

    Marra, John J.; Wessell, Brian J.; James, Allister W.; Marsh, Jan H.; Gear, Paul J.

    2017-08-08

    A vane assembly (10) having: an airfoil (12) and a shroud (14) held together without metallurgical bonding there between; a channel (22) disposed circumferentially about the airfoil (12), between the airfoil (12) and the shroud (14); and a seal (20) disposed in the channel (22), wherein during operation of a turbine engine having the vane assembly (10) the seal (20) has a sufficient ductility such that a force generated on the seal (20) resulting from relative movement of the airfoil (12) and the shroud (14) is sufficient to plastically deform the seal (20).

  18. Quick-sealing design for radiological containment

    International Nuclear Information System (INIS)

    Rampdla, D.S.; Speer, E.

    1991-01-01

    This patent describes 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

  19. Quick-sealing design for radiological containment

    International Nuclear Information System (INIS)

    Rampolia, D.S.; Speer, E.

    1990-01-01

    This patent describes 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

  20. Quick-sealing design for radiological containment

    Science.gov (United States)

    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.

  1. Bingham Sealing and Application in Vacuum Clamping

    Science.gov (United States)

    Yao, S. M.; Teo, Wee Kin; Geng, Zunmin; Turner, Sam; Ridgway, Keith

    2011-12-01

    Vacuum clamping is extensively used in shell machining. In this paper a Bingham Sealing (BS) is presented and formulized based on Bingham plastic performance. The sealing capability of BS is evaluated in various cases. A new Bingham plastic is developed and the yield stress is measured. The performances of "O"ring sealing and BS with the developed Bingham plastic are compared to the static experiment. In this experiment the same vacuum is achieved and the distortion of the blade with BS is better than that with "O" ring sealing.

  2. Bingham Sealing and Application in Vacuum Clamping

    International Nuclear Information System (INIS)

    Yao, S M; Teo, Wee Kin; Geng Zunmin; Turner, Sam; Ridgway, Keith

    2011-01-01

    Vacuum clamping is extensively used in shell machining. In this paper a Bingham Sealing (BS) is presented and formulized based on Bingham plastic performance. The sealing capability of BS is evaluated in various cases. A new Bingham plastic is developed and the yield stress is measured. The performances of Or ing sealing and BS with the developed Bingham plastic are compared to the static experiment. In this experiment the same vacuum is achieved and the distortion of the blade with BS is better than that with 'O' ring sealing.

  3. Byzantine seals from the Ras fortress

    Directory of Open Access Journals (Sweden)

    Ivanišević Vujadin

    2013-01-01

    Full Text Available In this paper, seals found at the location of the Ras fortress (Tvrđava Ras have been published. Inscriptions on these seals show that they used to belong to persons which could be identified with certain military commanders who served under Alexios I Komnenos. The seals in question are: the seals of protonobelissimos Eustathios Kamytzes, Constantine Dalassenos Doukas, protoproedros and doux Constantine Kekaumenos and a certain person called Alexios. [Projekat Ministarstva nauke Republike Srbije, br. 177021 i br. 177032

  4. 48 CFR 14.101 - Elements of sealed bidding.

    Science.gov (United States)

    2010-10-01

    ... CONTRACTING METHODS AND CONTRACT TYPES SEALED BIDDING Use of Sealed Bidding 14.101 Elements of sealed bidding. Sealed bidding is a method of contracting that employs competitive bids, public opening of bids, and... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Elements of sealed bidding...

  5. Ceramic/metal seals. [refractory materials for hermetic seals for lighium-metal sulfide batteries

    Science.gov (United States)

    Bredbenner, A. M.

    1977-01-01

    Design criteria are discussed for a hermetic seal capable of withstanding the 450 C operating temperature of a lithium-metal sulfide battery system. A mechanical seal consisting of two high strength alloy metal sleeves welded or brazed to a conductor assembly and pressed onto a ceramic is described. The conductor center passes through the ceramic but is not sealed to it. The seal is effected on the outside of the taper where the tubular part is pressed down over and makes contact.

  6. Seals at sea: modelling seal distribution in the German bight based on aerial survey data

    NARCIS (Netherlands)

    Herr, H.; Scheidat, M.; Lehnert, K.; Siebert, U.

    2009-01-01

    The Wadden Sea is an important habitat for harbour seals and grey seals. They regularly haul-out on sandbanks and islands along the coast. Comparably little is known about the time seals spend at sea and how they use the remainder of the North Sea. Yet, human activity in offshore waters is

  7. Albinistic common seals (Phoca vitulina) and melanistic grey seals (Halichoerus grypus) rehabilitated in the Netherlands

    NARCIS (Netherlands)

    Osinga, Nynke; 't Hart, Pieter; Vader, Pieter C. van Voorst

    2010-01-01

    The Seal Rehabilitation and Research Centre (SRRC) in Pieterburen, The Netherlands, rehabilitates seals from the waters of the Wadden Sea, North Sea and Southwest Delta area. Incidental observations of albinism and melanism in common and grey seals are known from countries surrounding the North Sea.

  8. Optimizing dc-resistance of a foil wounded toroidal inductor combining matlab and comsol

    DEFF Research Database (Denmark)

    Schneider, Henrik; Andersen, Thomas; Knott, Arnold

    2013-01-01

    An optimization routine is presented to optimize the shape of a foil winding of a toroid inductor in terms of the DC resistance. MATLAB was used to define the geometry of the foil winding and COMSOL was used to import the geometry and create a 3D finite element model. The initial parameters...

  9. Prism Foil from an LCD Monitor as a Tool for Teaching Introductory Optics

    Science.gov (United States)

    Planinsic, Gorazd; Gojkosek, Mihael

    2011-01-01

    Transparent prism foil is part of a backlight system in LCD monitors that are widely used today. This paper describes the optical properties of the prism foil and several pedagogical applications suitable for undergraduate introductory physics level. Examples include experiments that employ refraction, total internal reflection, diffraction and…

  10. Large area flexible lighting foils using distributed bare LED dies on polyester substrates

    NARCIS (Netherlands)

    Ende, D.A. van den; Kusters, R.H.L.; Cauwe, M.; Waal, A. van der; Brand, J. van den

    2013-01-01

    Integration of LEDs on flexible foil substrates is of interest for flexible lighting applications and for backlights for flexible displays. Such a large area lighting device can be made by integrating a matrix of closely spaced LEDs on a flexible foil substrate. Preferably, these LEDs are integrated

  11. Vortex-wake interactions of a flapping foil that models animal swimming and flight

    NARCIS (Netherlands)

    Lentink, D.; Muijres, F.T.; Donker-Duyvis, F.J.; Leeuwen, van J.L.

    2008-01-01

    The fluid dynamics of many swimming and flying animals involves the generation and shedding of vortices into the wake. Here we studied the dynamics of similar vortices shed by a simple two-dimensional flapping foil in a soap-film tunnel. The flapping foil models an animal wing, fin or tail in

  12. Long-Term Memory for Pictures under Conditions of Difficult Foil Discriminability.

    Science.gov (United States)

    Homa, Donald; Viera, Cynthia

    Research has demonstrated that subjects are sensitive to both thematic and non-thematic information in pictorial stimuli. Three experiments were conducted to investigate memory for pictures under conditions of difficult foil discriminability and lengthy retention intervals. The foils differed from the studied persons in the number and quality of…

  13. Bonding bare die LEDs on PET foils for lighting applications: Thermal design modeling and bonding experiments

    NARCIS (Netherlands)

    Ende, D.A. van den; Kusters, R.H.L.; Cauwe, M.; Waal, A. van der; Brand, J. van den

    2012-01-01

    Integration of LEDs on flexible foil substrates is of interest for flexible lighting applications and flexible photonic devices. A matrix of LEDs on a foil combined with a diffuser can be a potential alternative for flexible OLED lighting devices. Preferably, these LEDs are integrated in an

  14. Corrections in the gold foil activation method for determination of neutron beam density

    DEFF Research Database (Denmark)

    Als-Nielsen, Jens Aage

    1967-01-01

    A finite foil thickness and deviation in the cross section from the 1ν law imply corrections in the determination of neutron beam densities by means of foil activation. These corrections, which depend on the neutron velocity distribution, have been examined in general and are given in a specific...

  15. Identification of stiffness and damping characteristics of axial air-foil bearings

    NARCIS (Netherlands)

    Arora, Vikas; Arora, Vikas; van der Hoogt, Peter; Aarts, Ronald G.K.M.; de Boer, Andries

    2011-01-01

    Air-foil bearings (AFBs) are self acting hydrodynamic bearings made from sheet metal foils comprised of at least two layers. The innermost “top foil” layer traps a gas pressure film that supports a load while the layer or layers underneath provide an elastic foundation. AFBs are currently used in

  16. Compositional characterization of thin foil by instrumental heavy ion activation analysis

    International Nuclear Information System (INIS)

    Chowdhury, D.P.; Pal, Sujit; Guin, R.; Saha, S.K.; Venkataramani, B.

    2007-01-01

    The elemental composition of a thin (2 mm) Havar foil was determined by instrumental heavy ion activation analysis (HIAA). The recoiled products, coming out of thin target, were separated and absorbed in graded thickness of aluminum catcher foils as per their recoil ranges. Activation technique was followed for the quantitative estimation using elemental standards by comparator technique. (author)

  17. Multi-electrode double layer capacitor having single electrolyte seal and aluminum-impregnated carbon cloth electrodes

    Science.gov (United States)

    Farahmandi, C. Joseph; Dispennette, John M.; Blank, Edward; Kolb, Alan C.

    1999-01-19

    A single cell, multi-electrode high performance double layer capacitor includes first and second flat stacks of electrodes adapted to be housed in a closeable two-part capacitor case which includes only a single electrolyte seal. Each electrode stack has a plurality of electrodes connected in parallel, with the electrodes of one stack being interleaved with the electrodes of the other stack to form an interleaved stack, and with the electrodes of each stack being electrically connected to respective capacitor terminals. A porous separator sleeve is inserted over the electrodes of one stack before interleaving to prevent electrical shorts between the electrodes. The electrodes are made by folding a compressible, low resistance, aluminum-impregnated carbon cloth, made from activated carbon fibers, around a current collector foil, with a tab of the foils of each electrode of each stack being connected in parallel and connected to the respective capacitor terminal. The height of the interleaved stack is somewhat greater than the inside height of the closed capacitor case, thereby requiring compression of the interleaved electrode stack when placed inside of the case, and thereby maintaining the interleaved electrode stack under modest constant pressure. The closed capacitor case is filled with an electrolytic solution and sealed. A preferred electrolytic solution is made by dissolving an appropriate salt into acetonitrile (CH.sub.3 CN). In one embodiment, the two parts of the capacitor case are conductive and function as the capacitor terminals.

  18. Design optimization of backup seal for sodium cooled fast breeder reactor

    International Nuclear Information System (INIS)

    Sinha, N.K.; Ghosh, P.; Saha, A.; Mukhopadhyay, R.; Raj, Baldev; Chetal, S.C.

    2012-01-01

    Highlights: ► Design arrived from fourteen geometric options by finite element analysis. ► Seal geometry, size, compression, contact pressure, stress and compression load optimized. ► Effects of reduced fluoroelastomer strength at 110 °C, strain rate and stress-softening incorporated. ► Ageing, friction, tolerances, batch-to-batch/production variations in fluoroelastomer considered. ► Procedure applicable to other elastomeric seals of Fast Breeder Reactors. -- Abstract: Design optimization of static, fluoroelastomer backup seals for the 500 MWe, Prototype Fast Breeder Reactor (PFBR) is depicted. 14 geometric variations of a solid trapezoidal cross-section were studied by finite element analysis (FEA) to arrive at a design with hollowness and double o-ring contours on the sealing face. The seal design with squeeze of 5 mm assures failsafe operation for at least 10 years under a differential pressure of 25 kPa and ageing influences of fluid (air), temperature (110 °C) and γ radiation (23 mGy/h) in reactor. Hybrid elements of 1 mm length, regular integration, Mooney–Rivlin material model and Poisson’s ratio of 0.493 were used in axisymmetric analysis scheme. Possible effects of reduced fluoroelastomer strength at 110 °C, ageing, friction, tolerances in reactor scale, testing conditions during FEA data generation and batch-to-batch/production variations in seal material were considered to ensure adequate safety margin at the end of design life. The safety margin and numerical prediction accuracy could be improved further by using properties of specimens extracted from seal. The approach is applicable to other low pressure, moderate temperature elastomeric sealing applications of PFBR, mostly operating under maximum strain of 50%.

  19. European cinema: face to face with Hollywood

    NARCIS (Netherlands)

    Elsaesser, T.

    2005-01-01

    In the face of renewed competition from Hollywood since the early 1980s and the challenges posed to Europe's national cinemas by the fall of the Wall in 1989, independent filmmaking in Europe has begun to re-invent itself. European Cinema: Face to Face with Hollywood re-assesses the different

  20. Corkscrew Seals: Grey Seal (Halichoerus grypus) Infanticide and Cannibalism May Indicate the Cause of Spiral Lacerations in Seals.

    Science.gov (United States)

    Brownlow, Andrew; Onoufriou, Joseph; Bishop, Amanda; Davison, Nicholas; Thompson, Dave

    2016-01-01

    Large numbers of dead seals with characteristic spiral lesions have been washing ashore around the North Atlantic over the past two decades. Interactions with ship propellers and shark predation have been suggested as the likely causal mechanisms. However, new evidence points towards a more likely candidate: grey seal predation. An adult male grey seal was observed and recorded catching, killing and eating five weaned grey seal pups over a period of one week on the Isle of May, Scotland. A further 9 carcasses found in the same area exhibited similar injuries. Post mortem analysis of lesions indicated the wound characteristics were similar to each other and in 12 of the 14 carcasses analysed, were indistinguishable from carcasses previously attributed to propeller interaction. We therefore propose that most of the seal carcasses displaying spiral lacerations in the UK are caused by grey seal predation. Cases in other locations should be re-evaluated using the scoring system presented here to identify whether grey seal predation is a major cause of mortality in phocid seals.

  1. Mapping Teacher-Faces

    Science.gov (United States)

    Thompson, Greg; Cook, Ian

    2013-01-01

    This paper uses Deleuze and Guattari's concept of faciality to analyse the teacher's face. According to Deleuze and Guattari, the teacher-face is a special type of face because it is an "overcoded" face produced in specific landscapes. This paper suggests four limit-faces for teacher faciality that actualise different mixes of significance and…

  2. Irradiation tests of 99Mo isotope production targets employing uranium metal foils

    International Nuclear Information System (INIS)

    Hofman, G.L.; Wiencek, T.C.; Wood, E.L.; Snelgrove, J.L.; Suripto, A.; Nasution, H.; Lufti-Amin, D.; Gogo, A.

    1996-01-01

    Most of the world's supply of 99 mTc for medical purposes is currently produced from the decay of 99 Mo derived from the fissioning of high-enriched uranium (HEU). Substitution of low-enriched uranium (LEU) metal foils for the HEU UO 2 used in current target designs will allow equivalent 99 Mo yields with little change in target geometries. Substitution of uranium metal for uranium alloy and aluminide in other target designs will also allow the conversion of HEU to LEU. Several uranium-metal-foil targets have been fabricated at ANL and irradiated to prototypic burnup in the Indonesian RSG-GAS reactor. Postirradiation examination of the initial test indicated that design modifications were required to allow the irradiated foil to be removed for chemical processing. The latest test has shown good irradiation behavior, satisfactory dismantling and foil removal when the U-foil is separated from its containment by metallic, fission-recoil absorbing barriers. (author)

  3. Foil assisted replica molding for fabrication of microfluidic devices and their application in vitro.

    Science.gov (United States)

    Micheal, Issac J; Vidyasagar, Aditya J; Bokara, Kiran Kumar; Mekala, Naveen Kumar; Asthana, Amit; Rao, Ch Mohan

    2014-10-07

    We present a simple, rapid, benchtop, Foil Assisted Rapid Molding (FARM) method for the fabrication of microfluidic devices. This novel technique involves the use of aluminium foil, pen and an X-Y plotter to create semi-circular or plano-concave, shallow microchannels. It is an easy do-it-yourself (DIY) technique for creating a microfluidic device in three simple steps: (1) create a channel design using the CAD software, (2) plot the patterns on aluminium foil and (3) use the reverse of the engraved foil as a mold to create microfluidic devices. In this report, we present a detailed study of the proposed method by varying a range of parameters such as foil thickness, tip material, and tip sizes and by investigating their effect on the creation of channels with varying geometry. Furthermore, we demonstrated the cytocompatibility of these devices in vitro.

  4. Lead foil in dental X-ray film: Backscattering rejection or image intensifier?

    Energy Technology Data Exchange (ETDEWEB)

    Hönnicke, M.G., E-mail: marcelo.honnicke@unila.edu.br [Universidade Federal da Integração Latino-Americana, Foz do Iguaçu (Brazil); Delben, G.J. [Faculdade de Tecnologia Tupy, Curitiba (Brazil); Godoi, W.C. [Universidade Tecnológica Federal do Paraná, Curitiba (Brazil); Swinka-Filho, V. [Instituto de Tecnologia para o Desenvolvimento – LACTEC, Curitiba (Brazil)

    2014-11-01

    Dental X-ray films are still largely used due to sterilization issues, simplicity and, mainly, economic reasons. These films almost always are double coated (double emulsion) and have a lead foil in contact with the film for X-ray backscattering rejection. Herein we explore the use of the lead foil as an image intensifier. In these studies, spatial resolution was investigated when images were acquired on the dental X-ray films with and without the lead foil. Also, the lead foil was subjected to atomic analysis (fluorescent measurements) and structure analysis (X-ray diffraction). We determined that the use of the lead foil reduces the exposure time, however, does not affect the spatial resolution on the acquired images. This suggests that the fluorescent radiation spread is smaller than the grain sizes of the dental X-ray films.

  5. Room temperature thin foil SLIM-cut using an epoxy paste: experimental versus theoretical results

    International Nuclear Information System (INIS)

    Bellanger, Pierre; Serra, Joao; Bouchard, Pierre-Olivier; Bernacki, Marc

    2015-01-01

    The stress induced lift-off method (SLIM) -cut technique allows the detachment of thin silicon foils using a stress inducing layer. In this work, results of SLIM-cut foils obtained using an epoxy stress inducing layer at room temperature are presented. Numerical analyses were performed in order to study and ascertain the important experimental parameters. The experimental and simulation results are in good agreement. Indeed, large area (5 × 5 cm 2 ) foils were successfully detached at room temperature using an epoxy thickness of 900 μm and a curing temperature of 150 °C. Moreover, three foils (5 × 3 cm 2 ) with thickness 135, 121 and 110 μm were detached from the same monocrystalline substrate. Effective minority carrier lifetimes of 46, 25 and 20 μs were measured using quasi-steady-state photoconductance technique in these foils after iodine ethanol surface passivation. (paper)

  6. Nondestructive analysis of silver in gold foil using synchrotron radiation X-ray fluorescence spectrometry

    International Nuclear Information System (INIS)

    Kasamatsu, Masaaki; Suzuki, Yasuhiro; Suzuki, Shinichi; Nakanishi, Toshio; Shimoda, Osamu; Nishiwaki, Yoshinori; Miyamoto, Naoki

    2005-01-01

    Small particles of gold foil detached from an indoor decoration might be important evidence to associate a suspect with a crime scene. We have investigated the application of elemental analysis using synchrotron radiation X-ray fluorescence spectrometry to discriminate small particles of gold foil. Eight kinds of gold foil samples collected in Japan were used in the experiments. As a result of synchrotron radiation X-ray fluorescence spectrometry, only two elements, gold and silver, were detected from all gold foil samples. The intensity ratios of AgK α /AuL α showed good correlation with the content ratios of Ag/Au. The variation of intensity ratio within a same sample was sufficiently small compared with those of different samples. Therefore the comparison of this intensity ratio can be an effective method to discriminate small particles originating from different types of gold foil. (author)

  7. Irradiation tests of 99Mo isotope production targets employing uranium metal foils

    International Nuclear Information System (INIS)

    Hofman, G.L.; Wiencek, T.C.; Wood, E.L.; Snelgrove, J.L.; Suripto, A.; Nasution, H.; Lufti-Amin, D.; Gogo, A.

    1996-01-01

    Most of the world's supply of 99m Tc for medical purposes is currently produced form the decay of 99 Mo derived from the fissioning of high-enriched uranium (HEU). Substitution of low-enriched uranium (LEU) metal foils for the HEU UO 2 used in current target designs will allow equivalent 99 Mo yields with little change in target geometries. Substitution of uranium metal for uranium alloy and aluminide in other target designs will also allow the conversion of HEU to LEU. Several uranium-metal-foil targets have been fabricated at ANL and irradiated to prototypic burnup in the Indonesian RSG-GAS reactor. Postirradiation examination of the initial test indicated that design modifications were required to allow the irradiated foil to be removed for chemical processing. The latest test has shown good irradiation behavior, satisfactory dismantling and foil removal when the U-foil is separated from its containment by metallic, fission-recoil absorbing barriers

  8. Report on Plasma Spraying of Full-Sized Foils (FY13)

    Energy Technology Data Exchange (ETDEWEB)

    Hollis, Kendall J. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2014-02-27

    This report is the deliverable fulfilling task B40700. The application of the Zr diffusion barrier between the U-­Mo fuel and the Al cladding has been an ongoing area of research [1-8]. The goal of the research described in this report was to demonstrate the plasma spraying technique for depositing zirconium (Zr) onto full sized U-Mo foils to demonstrate scale up of the process from the mini foil samples (1”x4”x ~0.015”) coated previously. Full size denotes one of the actual fuel foil sizes for one of the five research reactors (MURR, NIST, MIT, HFIR, ATR) to be converted to LEU fuel in the US research reactor Convert program. The smallest full sized fuel foil is for the NIST reactor with a size of 11.37”x2.436”x0.020”. The largest full sized fuel foil is for the ATR reactor with a size of 48.01”x3.43”x0.020”. The widest full sized fuel foil is for the MURR reactor with a size of 24”x4.052”x0.020”. The current LANL vacuum plasma spray system can accommodate a foil length of 24” or less. Therefore, as a demonstration of the widest foil in the program and the maximum length foil that can be processed on the current LANL system, a nominal 24”x4”x0.020” foil was chosen as the goal for scale up activities.

  9. Machine Vision Inspection of Polymeric Traypack Seal Areas

    National Research Council Canada - National Science Library

    Coburn, John

    2002-01-01

    .... Since entrapped matter can lead to open seals, defects, and seal anomalies, a method of measurement for seal area contamination is useful in quantifying effects of filler changes, line speeds, and product formulations...

  10. Sealing of boreholes using natural, compatible materials: Granular salt

    International Nuclear Information System (INIS)

    Finley, R.E.; Zeuch, D.H.; Stormont, J.C.; Daemen, J.J.K.

    1994-01-01

    Granular salt can be used to construct high performance permanent seals in boreholes which penetrate rock salt formations. These seals are described as seal systems comprised of the host rock, the seal material, and the seal rock interface. The performance of these seal systems is defined by the complex interactions between these seal system components through time. The interactions are largely driven by the creep of the host formation applying boundary stress on the seal forcing host rock permeability with time. The immediate permeability of these seals is dependent on the emplaced density. Laboratory test results suggest that careful emplacement techniques could results in immediate seal system permeability on the order of 10 -16 m 2 to 10 -18 m 2 (10 -4 darcy to 10 -6 ). The visco-plastic behavior of the host rock coupled with the granular salts ability to ''heal'' or consolidate make granular salt an ideal sealing material for boreholes whose permanent sealing is required

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

    Science.gov (United States)

    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...

  12. Test preparation and lifetime measurement of very thin carbon stripper foils made by a controlled DC arc-discharge method

    CERN Document Server

    Sugai, I; Oyaizu, M; Kawakami, H; Hattori, Y; Kawasaki, K; Hayashizaki, N

    2002-01-01

    We have prepared very thin plastic supported carbon stripper foils (1.2+-0.3 mu g/cm sup 2) using a controlled DC arc-discharge (CDAD) method. The lifetime of these foils was measured with 3.2 MeV Ne sup + ions. These foils recorded lifetimes about four times longer at the maximum and three times longer on the average than those commercially available foils produced by evaporation-condensation.

  13. Design, construction and testing of underground seals

    CSIR Research Space (South Africa)

    Cook, AP

    2000-01-01

    Full Text Available the structural design or material requirements for seals, but also require an overpressure of 140 kPa, and this within 24 hours of construction. Approved systems for seal construction from MSHA are concrete blocks, Omega 384 foam blocks, cementitious foam........................................................................................................................ 7 2.1.2 Masonry ....................................................................................................................... 7 2.1.3 Concrete...

  14. Space Environment's Effects on Seal Materials

    Science.gov (United States)

    deGroh, Henry C., III; Daniels, Christopher C.; Dunlap, Patrick; Miller, Sharon; Dever, Joyce; Waters, Deborah; Steinetz, Bruce M.

    2007-01-01

    A Low Impact Docking System (LIDS) is being developed by the NASA Johnson Space Center to support future missions of the Crew Exploration Vehicle (CEV). The LIDS is androgynous, such that each system half is identical, thus any two vehicles or modules with LIDS can be coupled. Since each system half is a replica, the main interface seals must seal against each other instead of a conventional flat metal surface. These sealing surfaces are also expected to be exposed to the space environment when vehicles are not docked. The NASA Glenn Research Center (NASA GRC) is supporting this project by developing the main interface seals for the LIDS and determining the durability of candidate seal materials in the space environment. In space, the seals will be exposed to temperatures of between 50 to 50 C, vacuum, atomic oxygen, particle and ultraviolet radiation, and micrometeoroid and orbital debris (MMOD). NASA GRC is presently engaged in determining the effects of these environments on our candidate elastomers. Since silicone rubber is the only class of seal elastomer that functions across the expected temperature range, NASA GRC is focusing on three silicone elastomers: two provided by Parker Hannifin (S0-899-50 and S0-383-70) and one from Esterline Kirkhill (ELA-SA-401). Our results from compression set, elastomer to elastomer adhesion, and seal leakage tests before and after various simulated space exposures will be presented.

  15. Performance evaluation of chip seals in Idaho.

    Science.gov (United States)

    2010-08-01

    The intent of this research project is to identify a wide variety of parameters that influence the performance of pavements treated via chip seals within the State of Idaho. Chip sealing is currently one of the most popular methods of maintenance for...

  16. Population structure of ice-breeding seals.

    Science.gov (United States)

    Davis, Corey S; Stirling, Ian; Strobeck, Curtis; Coltman, David W

    2008-07-01

    The development of population genetic structure in ice-breeding seal species is likely to be shaped by a combination of breeding habitat and life-history characteristics. Species that return to breed on predictable fast-ice locations are more likely to exhibit natal fidelity than pack-ice-breeding species, which in turn facilitates the development of genetic differentiation between subpopulations. Other aspects of life history such as geographically distinct vocalizations, female gregariousness, and the potential for polygynous breeding may also facilitate population structure. Based on these factors, we predicted that fast-ice-breeding seal species (the Weddell and ringed seal) would show elevated genetic differentiation compared to pack-ice-breeding species (the leopard, Ross, crabeater and bearded seals). We tested this prediction using microsatellite analysis to examine population structure of these six ice-breeding species. Our results did not support this prediction. While none of the Antarctic pack-ice species showed statistically significant population structure, the bearded seal of the Arctic pack ice showed strong differentiation between subpopulations. Again in contrast, the fast-ice-breeding Weddell seal of the Antarctic showed clear evidence for genetic differentiation while the ringed seal, breeding in similar habitat in the Arctic, did not. These results suggest that the development of population structure in ice-breeding phocid seals is a more complex outcome of the interplay of phylogenetic and ecological factors than can be predicted on the basis of breeding substrate and life-history characteristics.

  17. Earlier pupping in harbour seals, Phoca vitulina

    NARCIS (Netherlands)

    Reijnders, P.J.H.; Brasseur, S.M.J.M.; Meesters, H.W.G.

    2010-01-01

    The annual reproductive cycle of most seal species is characterized by a tight synchrony of births. Typically, timing of birth shows little inter-annual variation. Here, however we show that harbour seals Phoca vitulina from the Wadden Sea (southeast North Sea) have shortened their yearly cycle,

  18. 39 CFR 2.4 - Seal.

    Science.gov (United States)

    2010-07-01

    ... 39 Postal Service 1 2010-07-01 2010-07-01 false Seal. 2.4 Section 2.4 Postal Service UNITED STATES... Secretary of State, and is required by 39 U.S.C. 207 to be judicially noticed. The Seal shall be in the... description of the Postal Service emblem is described at 39 CFR 221.7. ...

  19. Space Environment Effects on Silicone Seal Materials

    Science.gov (United States)

    deGroh, Henry C., III; Daniels, Christopher C.; Dever, Joyce A.; Miller, Sharon K.; Waters, Deborah L.; Finkbeiner, Joshua R.; Dunlap, Patrick H.; Steinetz, Bruce M.

    2010-01-01

    A docking system is being developed by the NASA to support future space missions. It is expected to use redundant elastomer seals to help contain cabin air during dockings between two spacecraft. The sealing surfaces are exposed to the space environment when vehicles are not docked. In space, the seals will be exposed to temperatures between 125 to -75 C, vacuum, atomic oxygen, particle and ultraviolet radiation, and micrometeoroid and orbital debris (MMOD). Silicone rubber is the only class of space flight-qualified elastomeric seal material that functions across the expected temperature range. NASA Glenn has tested three silicone elastomers for such seal applications: two provided by Parker (S0899-50 and S0383-70) and one from Esterline (ELA-SA-401). The effects of atomic oxygen (AO), UV and electron particle radiation, and vacuum on the properties of these three elastomers were examined. Critical seal properties such as leakage, adhesion, and compression set were measured before and after simulated space exposures. The S0899-50 silicone was determined to be inadequate for extended space seal applications due to high adhesion and intolerance to UV, but both S0383-70 and ELA-SA-401 seals were adequate.

  20. 19 CFR 101.7 - Customs seal.

    Science.gov (United States)

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Customs seal. 101.7 Section 101.7 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY GENERAL PROVISIONS § 101.7 Customs seal. (a) Design. According to the design furnished by the Department...

  1. Dura Seal recommendations for nuclear power plants

    International Nuclear Information System (INIS)

    Anon.

    1980-01-01

    Reactor systems (BWR, PWR and Candu) are briefly reviewed with reference to the pumping services encountered in each system, to indicate the conditions imposed on mechanical seals for nuclear power plant liquid handling equipment. A description of the Dura Seals used in each service is included. (U.K.)

  2. Sealing Occlusal Dentin Caries in Permanent Molars

    DEFF Research Database (Denmark)

    Qvist, Vibeke; Borum, Mette Kit; Møller, Kirsten Dynes

    2017-01-01

    .001). The median survival time for sealings not replaced by restorations was 7.3 y (CI, 6.4 y to NA). Survival of sealings was increased in patients with low caries risk and/or excellent oral hygiene, second molars compared with first molars, and lesions not extending the middle one-third of the dentin. Survival...

  3. Gas permeability through thin-foil x-ray filters

    Science.gov (United States)

    Tveekrem, June L.; Keski-Kuha, Ritva A.; Webb, Andrew T.

    1997-10-01

    We have measured the permeation rates of helium and water through thin-foil UV-blocking filters used in the ASTRO-E/x- ray spectrometer (XRS) instrument. In the XRS program, there is a concern that outgassed contaminants such as water could permeate through the outermost filter which will be at room temperature and freeze on the inner filters which will be at cryogenic temperatures. The filters tested consisted of approximately 1000 angstroms Al on approximately 1000 angstroms of either Lexan or polyimide. Measurements were made using a vacuum apparatus consisting essentially of two small chambers separated by the filter under test. A helium leak detector was used to measure helium permeation rates, and a residual gas analyzer (RGA) was used to detect water. Results discussed include permeation rate as a function of pressure difference across a filter, the ratio of helium permeation rate over water permeation rate, and the effect of the aluminum layer thickness on permeation.

  4. New membranes obtained by grafted irradiated PVDF foils

    Energy Technology Data Exchange (ETDEWEB)

    Mazzei, R. [Unidad de Actividades Tecnologicas y Agropecuarias, Laboratorio de Polimeros, Comision Nacional de Energia Atomica, Buenos Aires (Argentina); Universidad Tecnologica Nacional Facultad Regional, Buenos Aires (Argentina); Garcia Bermudez, G. [Gerencia de Investigacion y Aplicaciones, Laboratorio Tandar, Comision Nacional de Energia Atomica, Buenos Aires (Argentina); Escuela de Ciencia y Tecnologia, Universidad Nacional de General San Martin, Buenos Aires (Argentina); Consejo Nacional de Investigaciones Cientificas y Tecnicas, Buenos Aires (Argentina); Camporotondi, D.E., E-mail: camporotondi@cae.cnea.gov.ar [Unidad de Actividades Tecnologicas y Agropecuarias, Laboratorio de Polimeros, Comision Nacional de Energia Atomica, Buenos Aires (Argentina); Arbeitman, C. [Gerencia de Investigacion y Aplicaciones, Laboratorio Tandar, Comision Nacional de Energia Atomica, Buenos Aires (Argentina); Consejo Nacional de Investigaciones Cientificas y Tecnicas, Buenos Aires (Argentina); and others

    2012-09-15

    The present work describes a new method to produce membranes of poly(Acrylic-acid-Xmonomer) using the grafting procedure. PVDF foils irradiated with Ar{sup +} beam with energies between 30 and 150 keV were employed as substratum. Different combinations of monomers in water solutions were used: acrylic acid (AAc); acrylic acid-glycidyl methacrylate (AAc-GMA); acrylic acid-styrene (AAc-S), acrylic acid-N-isopropyl acrylamide (AAc-NIPAAm) and acrylic acid-N-isopropyl acrylamide-glycidyl methacrylate (AAc-NIPAAm-GMA). A large percentage of grafting results for specific values of: ion fluence and energy, AAc and sulfuric acid concentration, and different substrata PVDF polymorphous (alpha or beta). At a particular time of the grafting process, the poly(AAc-Xmonomer) membranes detach from the substratum and continue their grafting in the solution. This method is useful to produce increased replicated membranes of the irradiated original surface.

  5. Beam-foil spectroscopy of chlorine and sulfur ions

    International Nuclear Information System (INIS)

    Frot, D.; Barchewitz, R.; Cukier, M.; Bruneau, J.

    1987-01-01

    We report on the measurement of spectra of highly stripped chlorine and sulfur ions in the energy ranges of, respectively, 2900 - 3500 eV and 2300 - 2600 eV. The spectra have been obtained after excitation of ions travelling through a thin carbon foil. X-rays emitted by the emerging beam are analysed with a Johann-type bent crystal spectrometer. The observation angle with respect to the beam axis is 54 0 . The interpretation of the spectra is performed by comparing experimental results with Multiconfiguration Dirac-Fock (MCDF) calculated energies and intensities. All the lines are interpreted by 2p - ls transitions (K α spectrum) in excited ions with, respectively, H-, He-, Li-, Be- and B-like electron structures

  6. Synthesis of Homogenous Bilayer Graphene on Industrial Cu Foil

    Science.gov (United States)

    Luo, Wen-Gang; Wang, Hua-Feng; Cai, Kai-Ming; Han, Wen-Peng; Tan, Ping-Heng; Hu, Ping-An; Wang, Kai-You

    2014-06-01

    We synthesize the homogenous graphene films on cheap industrial Cu foils using low pressure chemical vapor deposition. The quality and the number of layers of graphene are characterized by Raman spectra. Through carefully tuning the growth parameters, we find that the growth temperature, hydrocarbon concentration and the growth time can substantially affect the growth of high-quality graphene. Both single and bilayer large size homogenous graphenes have been synthesized in optimized growth conditions. The growth of graphene on Cu surface is found to be self ceasing in the bilayer graphene process with the low solubility of carbon in Cu. Furthermore, we have optimized the transfer process, and clear graphene films almost free from impurity are successfully transferred onto Si/SiO2 substrates. The field effect transistors of bilayer graphene are fabricated, which demonstrates a maximum hole (electron) mobility of 4300 cm2 V-1s-1 (1920 cm2V-1s-1) at room temperature.

  7. Visualization of terahertz surface waves propagation on metal foils

    Science.gov (United States)

    Wang, Xinke; Wang, Sen; Sun, Wenfeng; Feng, Shengfei; Han, Peng; Yan, Haitao; Ye, Jiasheng; Zhang, Yan

    2016-01-01

    Exploitation of surface plasmonic devices (SPDs) in the terahertz (THz) band is always beneficial for broadening the application potential of THz technologies. To clarify features of SPDs, a practical characterization means is essential for accurately observing the complex field distribution of a THz surface wave (TSW). Here, a THz digital holographic imaging system is employed to coherently exhibit temporal variations and spectral properties of TSWs activated by a rectangular or semicircular slit structure on metal foils. Advantages of the imaging system are comprehensively elucidated, including the exclusive measurement of TSWs and fall-off of the time consumption. Numerical simulations of experimental procedures further verify the imaging measurement accuracy. It can be anticipated that this imaging system will provide a versatile tool for analyzing the performance and principle of SPDs. PMID:26729652

  8. Standard test methods of tension testing of metallic foil

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    1993-01-01

    1.1 These test methods cover the tension testing of metallic foil at room temperature in thicknesses less than 0.006 in. (0.150 mm). Note 1—Exception to these methods may be necessary in individual specifications or test methods for a particular material. 1.2 Units—The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard. 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

  9. Deposition of selenium coatings on beryllium foils. Revision 1

    International Nuclear Information System (INIS)

    Erikson, E.D.; Tassano, P.L.; Reiss, R.H.; Griggs, G.E.

    1984-01-01

    A technique for preparing selenium films on 50.8 micrometers thick beryllium foils is described. The selenium was deposited in vacuum from a resistance heated evaporation source. A water-cooled enclosure was used to minimize contamination of the vacuum system and to reduce the exposure of personnel to toxic and obnoxious materials. Profilometry measurements of the coatings indicated selenium thicknesses of 5.5, 12.9, 37.5, 49.8 and 74.5 micrometers. The control of deposition rate and of coating thickness was facilitated using a commercially available closed-loop programmable deposition controller. The x-ray transmission of the coated substrates was measured using a tritiated zirconium source. The transmissivities of the film/substrate combination are presented for the range of energies from 4 to 20 keV

  10. Seroprevalence of Antibodies against Seal Influenza A(H10N7) Virus in Harbor Seals and Gray Seals from the Netherlands

    NARCIS (Netherlands)

    Bodewes, Rogier; Garcia, Ana Rubio; Brasseur, Sophie M.; Conteras, Guillermo J.S.; De Bildt, Van Marco W.G.; Koopmans, Marion P.G.; Osterhaus, Albert D.M.E.; Kuiken, Thijs

    2015-01-01

    In the spring and summer 2014, an outbreak of seal influenza A(H10N7) virus infection occurred among harbor seals (Phoca vitulina) off the coasts of Sweden and Denmark. This virus subsequently spread to harbor seals off the coasts of Germany and the Netherlands. While thousands of seals were

  11. Seroprevalence of Antibodies against Seal Influenza A(H10N7) Virus in Harbor Seals and Gray Seals from the Netherlands

    NARCIS (Netherlands)

    Bodewes, Rogier; Rubio García, Ana; Brasseur, Sophie M; Sanchez Conteras, Guillermo J; van de Bildt, Marco W G; Koopmans, Marion P G; Osterhaus, Albert D M E; Kuiken, Thijs

    2015-01-01

    In the spring and summer 2014, an outbreak of seal influenza A(H10N7) virus infection occurred among harbor seals (Phoca vitulina) off the coasts of Sweden and Denmark. This virus subsequently spread to harbor seals off the coasts of Germany and the Netherlands. While thousands of seals were

  12. Effects of sonic booms on breeding gray seals and harbor seals on Sable Island, Canada.

    Science.gov (United States)

    Perry, Elizabeth A; Boness, Daryl J; Insley, Stephen J

    2002-01-01

    The Concorde produces audible sonic booms as it passes 15 km north of Sable Island, Nova Scotia, where gray and harbor seals occur year round. The purpose of this research was to assess how sonic booms affect these seals. The intensity of the booms was measured and three types of data (beach counts, frequency of behavior, and heart rate) were collected before and after booms during the breeding seasons of the two species. In addition to the data taken during breeding, beach counts were made before and after booms during the gray seal moult. The greatest range in overpressure within a single boom was 2.70 psf during gray seal breeding and 2.07 psf during harbor seal breeding. No significant differences were found in the behavior or beach counts of gray seals following sonic booms, regardless of the season. Beach counts and most behaviors of harbor seals also did not differ significantly following booms, however, harbor seals became more vigilant. The heart rates of four gray seal mothers and three pups showed no clear change as a result of booms, but six male harbor seals showed a nonsignificant tendency toward elevated heart rates during the 15-s interval of the boom. These results suggest sonic booms produced by the Concorde, in level flight at altitude and producing on average a sonic boom of 0.9 psf, do not substantially affect the breeding behavior of gray or harbor seals.

  13. Active Infrared Thermography for Seal Contamination Detection in Heat-Sealed Food Packaging

    Directory of Open Access Journals (Sweden)

    Karlien D’huys

    2016-11-01

    Full Text Available Packaging protects food products from environmental influences, assuring quality and safety throughout shelf life if properly performed. Packaging quality depends on the quality of the packaging material and of the closure or seal. A common problem possibly jeopardizing seal quality is the presence of seal contamination, which can cause a decreased seal strength, an increased packaging failure risk and leak formation. Therefore, early detection and removal of seal contaminated packages from the production chain is crucial. In this work, a pulsed-type active thermography method using the heated seal bars as an excitation source was studied for detecting seal contamination. Thermal image sequences of contaminated seals were recorded shortly after sealing. The detection performances of six thermal image processing methods, based on a single frame, a fit of the cooling profiles, thermal signal reconstruction, pulsed phase thermography, principal component thermography and a matched filter, were compared. High resolution digital images served as a reference to quantify seal contamination, and processed thermal images were mapped to these references. The lowest detection limit (equivalent diameter 0.60 mm was obtained for the method based on a fit of the cooling profiles. Moreover, the detection performance of this method did not depend strongly on the time after sealing at which recording of the thermal images was started, making it a robust and generally applicable method.

  14. Investigations of Shuttle Main Landing Gear Door Environmental Seals

    Science.gov (United States)

    Finkbeiner, Joshua; DeMange, Jeff; Dunlap, Pat; Steinetz, Bruce; Newswander, Daniel

    2006-01-01

    The Columbia Accident investigation Board (CAIB) requested an investigation into the MLG door seals. Initially, the MLG door seals were thought to have been a potential contributor to the loss of Columbia. These suspicions were later found to be untrue, but the seals remained as a cause for concern in future flights. MLG door seals comprised of thermal barrier and environmental seal. This study focuses on the environmental seal for the MLG door.

  15. The foil equilibration method for carbon in sodium

    International Nuclear Information System (INIS)

    Borgstedt, H.; Frees, G.; Peric, Z.

    1980-01-01

    Among the non-metallic impurities in sodium, carbon plays an important role since at high temperatures the structural materials exposed to sodium are subject to carburization and decarburization depending on the carbon activity of the sodium. Carburization of austenitic stainless steels leads to reduction in ductility and fatigue properties whereas decarburization results in a decrease in the high temperature creep strength. A knowledge of the carbon activities in sodium will help understanding of the carbon transfer phenomena in operating sodium systems of the fast reactors, and also carbon diffusion, microstructural stability and mechanical behaviour of materials under different service conditions. An understanding of the carbon behaviour in sodium becomes difficult in view of the complexities of the different species present as elemental carbon, carbide, acetylide, carbonate, and cyanide. Carbon estimation techniques for sodium presently in use are: chemical analytical methods, on-line carbon monitors, and oil equilibration method. Various chemical methods have been developed for the estimation of different species like acetylide, cyanide, carbonate, elemental carbon, and total carbon in sodium. All these methods are time consuming and subject to various errors. The on-line monitors developed for carbon in sodium are able to give continuous indication of carbon activities and have higher sensitivity than the chemical methods. A still more simple method for the determination of carbon activities is by the foil equilibration first published by Natesan et al. Because of its simplicity like the vanadium wire equilibration for oxygen it is being used widely for the estimation of carbon activities in sodium systems. Carbon concentrations in operating sodium systems estimated by this procedure by applying solubility relation to carbon activities have yielded very low values of carbon, lower than the sensitivity limits of the chemical estimation methods. Foil

  16. Influence of copper foil polycrystalline structure on graphene anisotropic etching

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Kamal P. [Department of Frontier Materials, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya 466-8555 (Japan); Mahyavanshi, Rakesh D. [Department of Physical Science and Engineering, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya 466-8555 (Japan); Kalita, Golap, E-mail: kalita.golap@nitech.ac.jp [Department of Frontier Materials, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya 466-8555 (Japan); Department of Physical Science and Engineering, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya 466-8555 (Japan); Tanemura, Masaki [Department of Frontier Materials, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya 466-8555 (Japan); Department of Physical Science and Engineering, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya 466-8555 (Japan)

    2017-01-30

    Graphical abstract: Hexagonal hole formation with anisotropic etching independent of the stripes and wrinkles in the synthesized graphene. We also observed variation in etched pattern of the graphene depending on the base Cu grain orientations, attributing to difference in nucleation and growth process. - Highlights: • Reveal the influence of copper polycrystalline structure on anisotropic etching of graphene. • Hexagonal hole formation with etching is observed to be independent of stripes and wrinkles in graphene. • Variation in etched pattern of graphene depending on the base Cu grain is confirmed. • This finding will help to understand the nature of microscopic etched pattern in graphene. - Abstract: Anisotropic etching of graphene and other two dimensional materials is an important tool to understand the growth process as well as enabling fabrication of various well-defined structures. Here, we reveal the influence of copper foil polycrystalline structure on anisotropic etching process of as-synthesized graphene. Graphene crystals were synthesized on the polycrystalline Cu foil by a low-pressure chemical vapor deposition (LPCVD) system. Microscopic analysis shows difference in shape, size and stripes alignment of graphene crystals with dissimilar nucleation within closure vicinity of neighboring Cu grains. Post-growth etching of such graphene crystals also significantly affected by the crystallographic nature of Cu grains as observed by the field emission scanning electron microscope (FE-SEM) and electron back scattered diffraction (EBSD) analysis. Hexagonal hole formation with anisotropic etching is observed to be independent of the stripes and wrinkles in the synthesized graphene. We also observed variation in etched pattern of the graphene depending on the base Cu grain orientations, attributing to difference in nucleation and growth process. The findings can facilitate to understand the nature of microscopic etched pattern depending on metal

  17. [Methods for sealing of corneal perforations].

    Science.gov (United States)

    Samoilă, O; Totu, Lăcrămioara; Călugăru, M

    2012-01-01

    A variety of corneal pathology can lead to corneal ulcers and perforations. A deep corneal ulcer may need surgical treatment to allow good volume restoration and reepithelisation. Corneal perforation must be sealed and when the perforation is large, the task of repairing the defect can be underwhelming. The elegant solution is the corneal transplant, but this is not always readily available, especially in undeveloped countries. We present here two cases with different solutions to seal the perforated cornea: the first one has a large peripheral defect and it is successfully sealed with scleral patch and the second one is central with small perforation and is successfully sealed with multilayered amniotic membrane. Both cases are followed for over 12 months and demonstrate good corneal restoration (both on clinical examination and corneal topography). Sclera and amniotic membrane can be used to seal corneal defects when corneal transplant is not readily available.

  18. Properties of Sealing Materials in Groundwater Wells

    DEFF Research Database (Denmark)

    Köser, Claus

    boreholes which in some cases can act as direct openings down to aquifers. The reasons for this may include bad or missing seal. In this context, Schmidt (1999) concluded that there is no proven way to make a clay seal with the desired tightness. This thesis deals primarily with the properties of bentonite...... pellets as sealing material in groundwater wells. The way and the pattern, in which bentonite pellets are deposited, have been shown to have an effect on the swelling pressure of the bentonite seal. During the transport phase of pellets from the terrain to a given sedimentation depth, a sorting process...... on the maximum swelling pressure; i) the bulk density of the sample, and ii) whether the sample is sorted or unsorted. CT scans (Computed Tomography) have been used to evaluate certain properties of bentonite seals in a limited volume. In this context, a set of algorithms to convert CT numbers (HU unit...

  19. Spring loaded compliant seal for high temperature use

    Science.gov (United States)

    Memmen, Robert L; Fedock, John A; Downs, James P

    2013-10-15

    A flexible seal having an X-shaped cross section that forms four contact points on four contact surfaces of two opposed seal slots. The flexible seal is used for a component in which the two seal slots undergo a large deflection such that the opposed slots are not aligned and a rigid seal will not form an adequate seal. The flexible seal can be used in a component of a combustor or a turbine in a gas turbine engine where opposed seal slots undergo the large deflection during operation.

  20. Does the seal licensing system in Scotland have a negative impact on seal welfare?

    Directory of Open Access Journals (Sweden)

    Laetitia Nunny

    2016-08-01

    Full Text Available This study examined the licensing system that permits seal shooting in Scotland, which was established under Part 6 Conservation of Seals of the Marine (Scotland Act 2010. Four approaches were used: data were collated and analyzed from both the Scottish Government and Scottish Marine Animal Stranding Scheme; a survey was sent to current license holders and informal interviews were conducted with key stakeholder types. Between February 2011 and the end of October 2015, 1229 gray seals and 275 common seals were reported shot under license to the Scottish Government. The numbers of seals reported as shot has reduced year-on-year since the licensing system was put in place. While some license holders, notably fish farms, were using some non-lethal forms of deterrent to reduce seal-related damage, these were often used alongside seal shooting. Of the seals reported as shot to the Scottish Government, only a small percentage were also reported to the Scottish Marine Animal Stranding Scheme, despite this being a licensing requirement. Only 2.3% of the shot gray seals and 4.5% of the shot common seals were necropsied. There is evidence from these necropsies that some seals had not died instantly or had not been shot in the manner recommended by the Scottish Seal Management Code of Practice. These preliminary results show that more carcasses need to be recovered and necropsied if the welfare implications of current seal shooting practice are to be properly assessed. The current legislation does not specify closed seasons to protect breeding seals and thirty-five per cent of necropsied seals were pregnant gray seals. Seals have also been shot during their lactation periods when pups are dependent on their mothers. This raises significant welfare concerns. The re-introduction of closed seasons specific to each species of seal is recommended along with greater effort to deploy non-lethal methods. Independent assessment of the number of seals being killed