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Sample records for gcfr pin streaming

  1. GCFR plant control system

    SciTech Connect

    Estrine, E.A.; Greiner, H.G.

    1980-05-01

    A plant control system is being designed for a gas-cooled fast breeder reactor (GCFR) demonstration plant. Control analysis is being performed as an integral part of the plant design process to ensure that control requirements are satisfied as the plant design evolves. The load control portion of the plant control system provides stable automatic (closed-loop) control of the plant over the 25% to 100% load range. Simulation results are presented to demonstrate load control system performance. The results show that the plant is controllable at full load with the control system structure selected, but gain scheduling is required to achieve desired performance over the load range.

  2. US GCFR demonstration plant design

    SciTech Connect

    Hunt, P.S.; Snyder, H.J.

    1980-05-01

    A general description of the US GCFR demonstration plant conceptual design is given to provide a context for more detailed papers to follow. The parameters selected for use in the design are presented and the basis for parameter selection is discussed. Nuclear steam supply system (NSSS) and balance of plant (BOP) component arrangements and systems are briefly discussed.

  3. GCFR thermal-hydraulic experiments

    SciTech Connect

    Schlueter, G.; Baxi, C.B.; Dalle Donne, M.; Gat, U.; Fenech, H.; Hanson, D.; Hudina, M.

    1980-01-01

    The thermal-hydraulic experimental studies performed and planned for the Gas-Cooled Fast Reactor (GCFR) core assemblies are described. The experiments consist of basic studies performed to obtain correlations, and bundle experiments which provide input for code validation and design verification. These studies have been performed and are planned at European laboratories, US national laboratories, Universities in the US, and at General Atomic Company

  4. GCFR shielding design and supporting experimental programs

    SciTech Connect

    Perkins, R.G.; Hamilton, C.J.; Bartine, D.

    1980-05-01

    The shielding for the conceptual design of the gas-cooled fast breeder reactor (GCFR) is described, and the component exposure design criteria which determine the shield design are presented. The experimental programs for validating the GCFR shielding design methods and data (which have been in existence since 1976) are also discussed.

  5. Reactor physics studies in the GCFR Phase III critical assembly

    SciTech Connect

    Morman, J A

    1980-03-01

    The third phase of the gas cooled fast reactor (GCFR) program, ZPR-9 Assembly 30, is based on a multi-zoned core of PuO/sub 2/-UO/sub 2/ with radial and axial blankets of UO/sub 2/. Studies performed in this assembly will be compared to the previous phases of the GCFR program and will help to define parameters in this power-flattened demonstration plant-type core. Measurements in the Phase III program included small sample reactivity worths of various materials, central reaction rates and reaction rate distributions, absorption-to-fission ratios and the central point conversion ratio and the worth of steam entry into a small central zone. The reactivity change associated with the construction of a central pin zone in the core and axial blanket was measured. Reaction rate and steam entry measurements were repeated in the pin environment. Standard analysis methods using ENDF/B-IV data are described and the results are compared to measurements performed during the program.

  6. Fabrication development of full-sized components for GCFR core assemblies

    SciTech Connect

    Lindgren, J.R.; Flynn, P.W.; Foster, L.C.

    1980-05-01

    This paper presents the status of the development of full-sized components for gas-cooled fast reactor (GCFR) core assemblies. Methods for ribbing of the fuel rod cladding, fabrication of grid spacers of two different designs, drawing of assembly flow ducts, and fabrication of fission gas collection manifolds by several methods are discussed.

  7. Pin care

    MedlinePlus

    There are different types of pin-cleaning solutions. The two most common solutions are: Sterile water A mixture of half normal saline and half hydrogen peroxide Use the solution that your surgeon recommends. Supplies you will need to ...

  8. Fuel pin

    DOEpatents

    Christiansen, D.W.; Karnesky, R.A.; Leggett, R.D.; Baker, R.B.

    1987-11-24

    A fuel pin for a liquid metal nuclear reactor is provided. The fuel pin includes a generally cylindrical cladding member with metallic fuel material disposed therein. At least a portion of the fuel material extends radially outwardly to the inner diameter of the cladding member to promote efficient transfer of heat to the reactor coolant system. The fuel material defines at least one void space therein to facilitate swelling of the fuel material during fission.

  9. Design and simulation of a plant control system for a GCFR demonstration plant

    SciTech Connect

    Estrine, E.A.; Greiner, H.G.

    1980-02-01

    A plant control system is being designed for a 300 MW(e) Gas Cooled Fast Breeder Reactor (GCFR) demonstration plant. Control analysis is being performed as an integral part of the plant design process to ensure that control requirements are satisfied as the plant design evolves. Plant models and simulations are being developed to generate information necessary to further define control system requirements for subsequent plant design iterations.

  10. Dowel pin

    DOEpatents

    Wojcik, Thaddeus A.

    1978-01-01

    Two abutting members are locked together by reaming a hole entirely through one member and at least partly through the other, machining a circular groove in each through hole just below the surface of the member, press fitting a dowel pin having a thin wall extension on at least one end thereof into the hole in both members, a thin wall extension extending into each through hole, crimping or snapping the thin wall extension into the grooves to positively lock the dowel pin in place and, if necessary, tack welding the end of the thin-wall extension in place.

  11. Locking Pull Pin

    NASA Technical Reports Server (NTRS)

    Killgrove, T. O.

    1986-01-01

    Proposed self-locking pull pin not accidentally released by shock or vibration but intentionally released by pull on lanyard. Any rotational movement of main pin traps secondary pin: prevents further rotation and disengagement of main pin.

  12. Analysis of the new GCFR upper and lower plenum flow-through shields

    SciTech Connect

    Cramer, S.N.; Reed, D.A.; Emmett, M.B.; Rouse, C.A.

    1980-09-14

    Analysis of the proposed GCFR upper and lower plenum flow-through shields has been performed using both discrete ordinate (DOT) and Monte Carlo (MORSE) methods. Several shields having one change of direction in the coolant path (chevron) and two changes of direction (herringbone) were investigated. The shields were modeled as unit cells with periodic boundary conditions. From plenum fluence calculations and design constraints at the reactor vessel liner, it was determined that all the shield configurations analyzed should be adequate for the necessary radiation attenuation.

  13. Oxidation of 316 stainless steel and other alloys in prototypic GCFR environments

    SciTech Connect

    Acharya, R.T.

    1980-05-01

    The oxidation behavior of type 316 stainless steel and candidate advanced alloys for the gas-cooled fast reactor (GCFR) is being investigated at General Atomic Company. The test program consists of oxidation tests in prototypic GCFR environments. Two tests have been completed to date and a third test is under way. The first test was performed in an environment containing a hydrogen/water ratio of 10. The oxidation behavior of all the alloys was good to excellent in this environment. Preferential oxidation of chromium was responsible for this behavior. The second test was performed in an environment containing a hydrogen/water ratio of 0.25, where both chromium and iron oxides are thermodynamically stable. Some of the alloys and some of the ribbed type 316 stainless steel test specimens showed unacceptable oxidation resistance in this environment. In the third test, presently under way, two different pretreatment procedures are being used to control the poor oxidation behavior observed in the second test. Early results show some degree of success.

  14. Pins for direct restorations.

    PubMed

    Papa, J; Wilson, P R; Tyas, M J

    1993-10-01

    Self-threading dentine pins permit the retention of large complex direct restorations but there are problems associated with their placement. Strain and crazing of dentine following pin insertion and pulpal and lateral perforations are common. Perforations can be avoided by operator awareness of tooth morphology. Strain and crazing has been found to be minimized by unscrewing the pin slightly after insertion, by using pins with a tap thread, and by using the smallest pin possible. Twist drill form and dulling affects the pin channel shape which in turn influences pin seating. A lack of standardization of pin and twist drill diameter and length has been implicated as the cause of poor pin retention. Manufacturers, in an attempt to standardize the depth of penetration of pins, have incorporated shoulders at the midpoint of the pin, which has met with varying success. More research in the area of limiting pin penetration is necessary, as well as attempts to improve the quality control of pin and twist drill manufacture. PMID:8227686

  15. Thermal performance of a pin-fin assembly

    NASA Astrophysics Data System (ADS)

    Babus'hag, R. F.; Akintunde, K.; Probert, S. D.

    1995-02-01

    The steady-state forced-convective cooling of a horizontally based pin-fin assembly has been investigated experimentally. The circular pin-fins protruded vertically upward from a horizontal base plate. For each in-line or staggered combination of specified pin-fins and air-flow rate, the optimal spacing-to-diameter ratios corresponding to the maximum rate of heat dissipation from the array have been deduced. The effect of changing the thermal conductivity of the pin-fin material has been studied. Designers should aim to have a spacing-to-diameter ratio of 1.04, in the span-wise direction, for all pin-fin systems; whereas, the ratio for the pin-fins in the stream-wise direction will depend upon what fin material is used and whether or not the pin-fins are staggered or aligned.

  16. Reusable Mechanical Pin Puller

    NASA Technical Reports Server (NTRS)

    Ngo, Son; Farley, Rodger; Devine, ED

    1991-01-01

    Reusable mechanical pin puller relatively simple spring-loaded trigger mechanism. Designed to save money and increase safety as substitute for costly and potentially dangerous pyrotechnic pin pullers used in development and testing of deployment mechanisms.

  17. Valve for fuel pin loading system

    DOEpatents

    Christiansen, David W.

    1985-01-01

    A cyclone valve surrounds a wall opening through which cladding is projected. An axial valve inlet surrounds the cladding. Air is drawn through the inlet by a cyclone stream within the valve. An inflatable seal is included to physically engage a fuel pin subassembly during loading of fuel pellets.

  18. Valve for fuel pin loading system

    DOEpatents

    Christiansen, D.W.

    1984-01-01

    A cyclone valve surrounds a wall opening through which cladding is projected. An axial valve inlet surrounds the cladding. Air is drawn through the inlet by a cyclone stream within the valve. An inflatable seal is included to physically engage a fuel pin subassembly during loading of fuel pellets.

  19. Nuclear fuel pin scanner

    DOEpatents

    Bramblett, Richard L.; Preskitt, Charles A.

    1987-03-03

    Systems and methods for inspection of nuclear fuel pins to determine fiss loading and uniformity. The system includes infeed mechanisms which stockpile, identify and install nuclear fuel pins into an irradiator. The irradiator provides extended activation times using an approximately cylindrical arrangement of numerous fuel pins. The fuel pins can be arranged in a magazine which is rotated about a longitudinal axis of rotation. A source of activating radiation is positioned equidistant from the fuel pins along the longitudinal axis of rotation. The source of activating radiation is preferably oscillated along the axis to uniformly activate the fuel pins. A detector is provided downstream of the irradiator. The detector uses a plurality of detector elements arranged in an axial array. Each detector element inspects a segment of the fuel pin. The activated fuel pin being inspected in the detector is oscillated repeatedly over a distance equal to the spacing between adjacent detector elements, thereby multiplying the effective time available for detecting radiation emissions from the activated fuel pin.

  20. Straight SU-8 pins

    NASA Astrophysics Data System (ADS)

    Safavieh, R.; Pla Roca, M.; Qasaimeh, M. A.; Mirzaei, M.; Juncker, D.

    2010-05-01

    SU-8 can be patterned with high resolution, is flexible and tough. These characteristics qualify SU-8 as a material for making spotting pins for printing DNA and protein microarrays, and it can potentially replace the commonly used silicon and steel pins that are expensive, brittle in the case of silicon and can damage the substrate during the printing process. SU-8, however, accumulates large internal stress during fabrication and, as a consequence, thin and long SU-8 structures bend and coil up, which precludes using it for long, freestanding structures such as pins. Here we introduce (i) a novel fabrication process that allows the making of 30 mm long, straight spotting pins that feature (ii) a new design and surface chemistry treatments for better capillary flow control and more homogeneous spotting. A key innovation for the fabrication is a post-processing annealing step with slow temperature ramping and mechanical clamping between two identical substrates to minimize stress buildup and render it symmetric, respectively, which together yield a straight SU-8 structure. SU-8 pins fabricated using this process are compliant and resilient and can buckle without damage during printing. The pins comprise a novel flow stop valve for accurate metering of fluids, and their surface was chemically patterned to render the outside of the pin hydrophobic while the inside of the slit is hydrophilic, and the slit thus spontaneously fills when dipped into a solution while preventing droplet attachment on the outside. A single SU-8 pin was used to print 1392 protein spots in one run. SU-8 pins are inexpensive, straightforward to fabricate, robust and may be used as disposable pins for microarray fabrication. These pins serve as an illustration of the potential application of ultralow stress SU-8 for making freestanding microfabricated polymer microstructures.

  1. PINS Spectrum Identification Guide

    SciTech Connect

    A.J. Caffrey

    2012-03-01

    The Portable Isotopic Neutron Spectroscopy—PINS, for short—system identifies the chemicals inside munitions and containers without opening them, a decided safety advantage if the fill chemical is a hazardous substance like a chemical warfare agent or an explosive. The PINS Spectrum Identification Guide is intended as a reference for technical professionals responsible for the interpretation of PINS gamma-ray spectra. The guide is divided into two parts. The three chapters that constitute Part I cover the science and technology of PINS. Neutron activation analysis is the focus of Chapter 1. Chapter 2 explores PINS hardware, software, and related operational issues. Gamma-ray spectral analysis basics are introduced in Chapter 3. The six chapters of Part II cover the identification of PINS spectra in detail. Like the PINS decision tree logic, these chapters are organized by chemical element: phosphorus-based chemicals, chlorine-based chemicals, etc. These descriptions of hazardous, toxic, and/or explosive chemicals conclude with a chapter on the identification of the inert chemicals, e.g. sand, used to fill practice munitions.

  2. Particle-bed gas-cooled fast reactor (PB-GCFR) design. Project final technical report (Sept 2001 - Aug 2003).

    SciTech Connect

    Taiwo, T. A.; Wei, T. Y. C.; Feldman, E. E.; Hoffman, E. A.; Fatone, M.; Holland, J. W.; Prokofiev, I. G.; Yang, W. S.; Palmiotti, G.; Hill, R. N.; Todosow, M.; Salvatores, M.; Gandini, A.

    2003-10-27

    The objective of this project is to develop a conceptual design of a particle-bed, gas-cooled fast reactor (PB-GCFR) core that meets the advanced reactor concept and enhanced proliferation-resistant goals of the US Department of Energy's NERI program. The key innovation of this project is the application of a fast neutron spectrum environment to enhance both the passive safety and transmutation characteristics of the advanced particle-bed and pebble-bed reactor designs. The PB-GCFR design is expected to produce a high-efficiency system with a low unit cost. It is anticipated that the fast neutron spectrum would permit small-sized units ({approx} 150 MWe) that can be built quickly and packaged into modular units, and whose production can be readily expanded as the demand grows. Such a system could be deployed globally. The goals of this two-year project are as follows: (1) design a reactor core that meets the future needs of the nuclear industry, by being passively safe with reduced need for engineered safety systems. This will entail an innovative core design incorporating new fuel form and type; (2) employ a proliferation-resistant fuel design and fuel cycle. This will be supported by a long-life core design that is refueled infrequently, and hence, reduces the potential for fuel diversion; (3) incorporate design features that permit use of the system as an efficient transmuter that could be employed for burning separated plutonium fuel or recycled LWR transuranic fuel, should the need arise; and (4) evaluate the fuel cycle for waste minimization and for the possibility of direct fuel disposal. The application of particle-bed fuel provides the promise of extremely high burnup and fission-product protection barriers that may permit direct disposal.

  3. Spring loaded locator pin assembly

    DOEpatents

    Groll, T.A.; White, J.P.

    1998-03-03

    This invention deals with spring loaded locator pins. Locator pins are sometimes referred to as captured pins. This is a mechanism which locks two items together with the pin that is spring loaded so that it drops into a locator hole on the work piece. 5 figs.

  4. Spring loaded locator pin assembly

    DOEpatents

    Groll, Todd A.; White, James P.

    1998-01-01

    This invention deals with spring loaded locator pins. Locator pins are sometimes referred to as captured pins. This is a mechanism which locks two items together with the pin that is spring loaded so that it drops into a locator hole on the work piece.

  5. Gas-Cooled Fast Breeder Reactor Preliminary Safety Information Document, Amendment 10. GCFR residual heat removal system criteria, design, and performance

    SciTech Connect

    Not Available

    1980-09-01

    This report presents a comprehensive set of safety design bases to support the conceptual design of the gas-cooled fast breeder reactor (GCFR) residual heat removal (RHR) systems. The report is structured to enable the Nuclear Regulatory Commission (NRC) to review and comment in the licensability of these design bases. This report also presents information concerning a specific plant design and its performance as an auxiliary part to assist the NRC in evaluating the safety design bases.

  6. PINS-3X Operations

    SciTech Connect

    E.H. Seabury

    2013-09-01

    Idaho National Laboratory’s (INL’s) Portable Isotopic Neutron Spectroscopy System (PINS) non-intrusively identifies the chemical fill of munitions and sealed containers. The PINS-3X variant of the system is used to identify explosives and uses a deuterium-tritium (DT) electronic neutron generator (ENG) as the neutron source. Use of the system, including possession and use of the neutron generator and shipment of the system components requires compliance with a number of regulations. This report outlines some of these requirements as well as some of the requirements in using the system outside of INL.

  7. Diffusion inspires selection of pinning nodes in pinning control

    NASA Astrophysics Data System (ADS)

    Zhou, Ming-Yang; He, Xingsheng; Fu, Zhong-Qian; Liao, Hao; Cai, Shi-min; Zhuo, Zhao

    2016-03-01

    The outstanding problem of controlling a complex network via pinning is related to network dynamics and has the potential to master large-scale real-world systems as well. This paper addresses the heart issue about how to choose pinning nodes for pinning control, where pinning control aims to control a network to an identical state by injecting feedback control signals to a small fraction of nodes. We explore networks' controllability from not only mathematical analysis, but also the aspects of network topology and information diffusion. Then, the connection between pinning control and information diffusion is given, and pinning node selection is transferred into multi-spreader problem in information diffusion. Based on information diffusion, a heuristic method is proposed to select pinning nodes by optimizing the spreading ability of multiple spreaders. The proposed method greatly improves the controllability of large practical networks, and provides a new perspective to investigate pinning node selection.

  8. Lever-Arm Pin Puller

    NASA Technical Reports Server (NTRS)

    Macmartin, Malcolm

    1994-01-01

    Mechanism holds retaining pins in place except when actuated to release pins quickly. Mechanism is integral part of cover designed to be removed with simple downward motion of hand. Before removal, mechanism secures cover in place. After removal, mechanism holds retaining pins for reuse.

  9. Pin puller impact shock attenuation

    NASA Technical Reports Server (NTRS)

    Auclair, G. F.; Leonard, B. S.; Robbins, R. E.; Proffitt, W. L.

    1976-01-01

    Design of a pin arresting mechanism for a pyrotechnically actuated pin puller is reviewed. The investigative approach is discussed and the impact shock test results for various candidate designs are presented. The selected pin arresting design reduced the peak value of the shock response spectrum by five to one.

  10. Spatial Pinning Control

    NASA Astrophysics Data System (ADS)

    Frasca, Mattia; Buscarino, Arturo; Rizzo, Alessandro; Fortuna, Luigi

    2012-05-01

    In this Letter, we introduce the concept of spatial pinning control for a network of mobile chaotic agents. In a planar space, N agents move as random walkers and interact according to a time-varying r-disk proximity graph. A control input is applied only to those agents which enter a given area, called control region. The control is effective in driving all the agents to a reference evolution and has better performance than pinning control on a fixed set of agents. We derive analytical conditions on the relative size of the control region and the agent density for the global convergence of the system to the reference evolution and study the system under different regimes inherited by the velocity.

  11. SIMULATE-4 pin power calculations

    SciTech Connect

    Bahadir, T.; Lindahl, S. Oe

    2006-07-01

    A new pin power reconstruction module has been implemented in Studsvik Scandpower's next generation nodal code, SIMULATE-4. Heterogeneous pin powers are calculated by modulating multi-group pin powers from the sub-mesh solver of SIMULATE-4 with pin form factors from single-assembly CASMO-5 lattice calculations. The multi-group pin power model captures instantaneous spectral effects, and actinide tracking on the assembly sub-mesh describes exposure-induced pin power variations. Model details and verification tests against high order multi-assembly transport methods are presented. The accuracy of the new methods is also demonstrated by comparing SIMULATE-4 calculations with measured critical experiment pin powers. (authors)

  12. The PIN-FORMED (PIN) protein family of auxin transporters

    PubMed Central

    2009-01-01

    Summary The PIN-FORMED (PIN) proteins are secondary transporters acting in the efflux of the plant signal molecule auxin from cells. They are asymmetrically localized within cells and their polarity determines the directionality of intercellular auxin flow. PIN genes are found exclusively in the genomes of multicellular plants and play an important role in regulating asymmetric auxin distribution in multiple developmental processes, including embryogenesis, organogenesis, tissue differentiation and tropic responses. All PIN proteins have a similar structure with amino- and carboxy-terminal hydrophobic, membrane-spanning domains separated by a central hydrophilic domain. The structure of the hydrophobic domains is well conserved. The hydrophilic domain is more divergent and it determines eight groups within the protein family. The activity of PIN proteins is regulated at multiple levels, including transcription, protein stability, subcellular localization and transport activity. Different endogenous and environmental signals can modulate PIN activity and thus modulate auxin-distribution-dependent development. A large group of PIN proteins, including the most ancient members known from mosses, localize to the endoplasmic reticulum and they regulate the subcellular compartmentalization of auxin and thus auxin metabolism. Further work is needed to establish the physiological importance of this unexpected mode of auxin homeostasis regulation. Furthermore, the evolution of PIN-based transport, PIN protein structure and more detailed biochemical characterization of the transport function are important topics for further studies. PMID:20053306

  13. Pip pin reliability and design

    NASA Technical Reports Server (NTRS)

    Skyles, Lane P.

    1994-01-01

    Pip pins are used in many engineering applications. Of particular interest to the aerospace industry is their use in various mechanism designs. Many payloads that fly aboard our nation's Space Shuttle have at least one actuated mechanism. Often these mechanisms incorporate pip pins in their design in order to fasten interfacing parts or joints. Pip pins are most often used when an astronaut will have a direct interface with the mechanism. This interfacing can be done during Space Shuttle mission EVA's (ExtraVehicular Activity). The main reason for incorporating pip pins is convenience and their ability to provide a quick release for interfacing parts. However, there are some issues that must be taken into account when using them in a design. These issues include documented failures and quality control problems when using substandard pip pins. A history of pip pins as they relate to the aerospace industry as well as general design features is discussed.

  14. Shock characterization of TOAD pins

    SciTech Connect

    Weirick, L.J.; Navarro, N.J.

    1995-08-01

    The purpose of this program was to characterize Time Of Arrival Detectors (TOAD) pins response to shock loading with respect to risetime, amplitude, repeatability and consistency. TOAD pins were subjected to impacts of 35 to 420 kilobars amplitude and approximately 1 ms pulse width to investigate the timing spread of four pins and the voltage output profile of the individual pins. Sets of pins were also aged at 45{degrees}, 60{degrees}, and 80{degrees}C for approximately nine weeks before shock testing at 315 kilobars impact stress. Four sets of pins were heated to 50.2{degrees}C (125{degrees}F) for approximately two hours and then impacted at either 50 or 315 kilobars. Also, four sets of pins were aged at 60{degrees}C for nine weeks and then heated to 50.2{degrees}C before shock testing at 50 and 315 kilobars impact stress, respectively. Particle velocity measurements at the contact point between the stainless steel targets and TOAD pins were made using a Velocity Interferometer System for Any Reflector (VISAR) to monitor both the amplitude and profile of the shock waves.

  15. Shock characterization of toad pins

    SciTech Connect

    Weirick, L.J.; Navarro, M.J.

    1996-05-01

    The purpose of this program was to characterize Time Of Arrival Detectors (TOAD) pins response to shock loading with respect to risetime, amplitude, repeatability and consistency. TOAD pins were subjected to impacts of 35 to 420 kilobars amplitude and approximately 1 ms pulse width to investigate the timing spread of four pins and the voltage output profile of the individual pins. Sets of pins were also aged at 45{degree}, 60{degree} and 80{degree}C for approximately nine weeks before shock testing at 315 kilobars impact stress. Four sets of pins were heated to 50.2{degree}C (125{degree}F) for approximately two hours and then impacted at either 50 or 315 kilobars. Also, four sets of pins were aged at 60{degree}C for nine weeks and then heated to 50.2{degree}C before shock testing at 50 and 315 kilobars impact stress, respectively. Particle velocity measurements at the contact point between the stainless steel targets and TOAD pins were made using a Velocity Interferometer System for Any Reflector (VISAR) to monitor both the amplitude and profile of the shock waves. {copyright} {ital 1996 American Institute of Physics.}

  16. Nondestrucive analysis of fuel pins

    DOEpatents

    Stepan, I.E.; Allard, N.P.; Suter, C.R.

    1972-11-03

    Disclosure is made of a method and a correspondingly adapted facility for the nondestructive analysis of the concentation of fuel and poison in a nuclear reactor fuel pin. The concentrations of fuel and poison in successive sections along the entire length of the fuel pin are determined by measuring the reactivity of a thermal reactor as each successive small section of the fuel pin is exposed to the neutron flux of the reactor core and comparing the measured reactivity with the reactivities measured for standard fuel pins having various known concentrations. Only a small section of the length of the fuel pin is exposed to the neutron flux at any one time while the remainder of the fuel pin is shielded from the neutron flux. In order to expose only a small section at any one time, a boron-10-lined dry traverse tube is passed through the test region within the core of a low-power thermal nuclear reactor which has a very high fuel sensitivity. A narrow window in the boron-10 lining is positioned at the core center line. The fuel pins are then systematically traversed through the tube past the narrow window such that successive small sections along the length of the fuel pin are exposed to the neutron flux which passes through the narrow window.

  17. Fuel pin cladding

    DOEpatents

    Vaidyanathan, Swaminathan; Adamson, Martyn G.

    1986-01-01

    An improved fuel pin cladding, particularly adapted for use in breeder reactors, consisting of composite tubing with austenitic steel on the outer portion of the thickness of the tube wall and with nickel and/or ferritic material on the inner portion of the thickness of the tube wall. The nickel forms a sacrificial barrier as it reacts with certain fission products thereby reducing fission product activity at the austenitic steel interface. The ferritic material forms a preventive barrier for the austenitic steel as it is immune to liquid metal embrittlement. The improved cladding permits the use of high density fuel which in turn leads to a better breeding ratio in breeder reactors, and will increase the threshold at which failure occurs during temperature transients.

  18. Fuel pin cladding

    DOEpatents

    Vaidyanathan, S.; Adamson, M.G.

    1983-12-16

    An improved fuel pin cladding, particularly adapted for use in breeder reactors, is described which consist of composite tubing with austenitic steel on the outer portion of the thickness of the tube wall and with nickel an/or ferritic material on the inner portion of the thickness of the tube wall. The nickel forms a sacrificial barrier as it reacts with certain fission products thereby reducing fission product activity at the austenitic steel interface. The ferritic material forms a preventive barrier for the austenitic steel as it is immune to liquid metal embrittlement. The improved cladding permits the use of high density fuel which in turn leads to a better breeding ratio in breeder reactors, and will increase the threshold at which failure occurs during temperature transients.

  19. Fuel pin cladding

    DOEpatents

    Vaidyanathan, S.; Adamson, M.G.

    1986-01-28

    Disclosed is an improved fuel pin cladding, particularly adapted for use in breeder reactors, consisting of composite tubing with austenitic steel on the outer portion of the thickness of the tube wall and with nickel and/or ferritic material on the inner portion of the thickness of the tube wall. The nickel forms a sacrificial barrier as it reacts with certain fission products thereby reducing fission product activity at the austenitic steel interface. The ferritic material forms a preventive barrier for the austenitic steel as it is immune to liquid metal embrittlement. The improved cladding permits the use of high density fuel which in turn leads to a better breeding ratio in breeder reactors, and will increase the threshold at which failure occurs during temperature transients. 2 figs.

  20. Anvil for Flaring PCB Guide Pins

    NASA Technical Reports Server (NTRS)

    Winn, E.; Turner, R.

    1985-01-01

    Spring-loaded anvil results in fewer fractured pins. New anvil for flaring guide pins in printed-circuit boards absorbs approximately 80 percent of press force. As result fewer pins damaged, and work output of flaring press greatly increased.

  1. Flavonoids Redirect PIN-mediated Polar Auxin Fluxes during Root Gravitropic Responses*S⃞

    PubMed Central

    Santelia, Diana; Henrichs, Sina; Vincenzetti, Vincent; Sauer, Michael; Bigler, Laurent; Klein, Markus; Bailly, Aurélien; Lee, Youngsook; Friml, Jir̆í; Geisler, Markus; Martinoia, Enrico

    2008-01-01

    The rate, polarity, and symmetry of the flow of the plant hormone auxin are determined by the polar cellular localization of PIN-FORMED (PIN) auxin efflux carriers. Flavonoids, a class of secondary plant metabolites, have been suspected to modulate auxin transport and tropic responses. Nevertheless, the identity of specific flavonoid compounds involved and their molecular function and targets in vivo are essentially unknown. Here we show that the root elongation zone of agravitropic pin2/eir1/wav6/agr1 has an altered pattern and amount of flavonol glycosides. Application of nanomolar concentrations of flavonols to pin2 roots is sufficient to partially restore root gravitropism. By employing a quantitative cell biological approach, we demonstrate that flavonoids partially restore the formation of lateral auxin gradients in the absence of PIN2. Chemical complementation by flavonoids correlates with an asymmetric distribution of the PIN1 protein. pin2 complementation probably does not result from inhibition of auxin efflux, as supply of the auxin transport inhibitor N-1-naphthylphthalamic acid failed to restore pin2 gravitropism. We propose that flavonoids promote asymmetric PIN shifts during gravity stimulation, thus redirecting basipetal auxin streams necessary for root bending. PMID:18718912

  2. Flavonoids redirect PIN-mediated polar auxin fluxes during root gravitropic responses.

    PubMed

    Santelia, Diana; Henrichs, Sina; Vincenzetti, Vincent; Sauer, Michael; Bigler, Laurent; Klein, Markus; Bailly, Aurélien; Lee, Youngsook; Friml, Jirí; Geisler, Markus; Martinoia, Enrico

    2008-11-01

    The rate, polarity, and symmetry of the flow of the plant hormone auxin are determined by the polar cellular localization of PIN-FORMED (PIN) auxin efflux carriers. Flavonoids, a class of secondary plant metabolites, have been suspected to modulate auxin transport and tropic responses. Nevertheless, the identity of specific flavonoid compounds involved and their molecular function and targets in vivo are essentially unknown. Here we show that the root elongation zone of agravitropic pin2/eir1/wav6/agr1 has an altered pattern and amount of flavonol glycosides. Application of nanomolar concentrations of flavonols to pin2 roots is sufficient to partially restore root gravitropism. By employing a quantitative cell biological approach, we demonstrate that flavonoids partially restore the formation of lateral auxin gradients in the absence of PIN2. Chemical complementation by flavonoids correlates with an asymmetric distribution of the PIN1 protein. pin2 complementation probably does not result from inhibition of auxin efflux, as supply of the auxin transport inhibitor N-1-naphthylphthalamic acid failed to restore pin2 gravitropism. We propose that flavonoids promote asymmetric PIN shifts during gravity stimulation, thus redirecting basipetal auxin streams necessary for root bending. PMID:18718912

  3. Automated fuel pin loading system

    DOEpatents

    Christiansen, D.W.; Brown, W.F.; Steffen, J.M.

    An automated loading system for nuclear reactor fuel elements utilizes a gravity feed conveyor which permits individual fuel pins to roll along a constrained path perpendicular to their respective lengths. The individual lengths of fuel cladding are directed onto movable transports, where they are aligned coaxially with the axes of associated handling equipment at appropriate production stations. Each fuel pin can be be reciprocated axially and/or rotated about its axis as required during handling steps. The fuel pins are inerted as a batch prior to welding of end caps by one of two disclosed welding systems.

  4. Automated fuel pin loading system

    DOEpatents

    Christiansen, David W.; Brown, William F.; Steffen, Jim M.

    1985-01-01

    An automated loading system for nuclear reactor fuel elements utilizes a gravity feed conveyor which permits individual fuel pins to roll along a constrained path perpendicular to their respective lengths. The individual lengths of fuel cladding are directed onto movable transports, where they are aligned coaxially with the axes of associated handling equipment at appropriate production stations. Each fuel pin can be reciprocated axially and/or rotated about its axis as required during handling steps. The fuel pins are inserted as a batch prior to welding of end caps by one of two disclosed welding systems.

  5. Pin1 in Neuronal Apoptosis

    PubMed Central

    Becker, Esther B.E.; Bonni, Azad

    2009-01-01

    While the role of the prolyl isomerase Pin1 in dividing cells has long been recognized, Pin1’s function in postmitotic neurons is poorly understood. We have identified a novel mechanism by which Pin1 mediates activation of the mitochondrial cell death machinery specifically in neurons. This perspective presents a sophisticated signaling pathway that triggers neuronal apoptosis upon JNK-mediated phosphorylation of the BH3-only protein BIMEL at serine 65. Pin1 is enriched at the mitochondria in neurons together with BIMEL and components of a neuron-specific JNK signaling complex and functions as a molecular switch that couples the phosphorylation of BIMEL by JNK to apoptosis specifically in neurons. We discuss how these findings relate to our understanding of the development of the nervous system and the pathogenesis of neurologic disorders. PMID:17568190

  6. Differential pressure pin discharge apparatus

    DOEpatents

    Oakley, David J.

    1987-01-01

    Disclosed is a discharge assembly for allowing elongate pins to be discharged from an area of relatively low pressure to an area of relatively greater pressure. The discharge assembly includes a duck valve having a lip piece made of flexible material. The flexible lip piece responds to a fluctuating pressure created downstream by an aspirator. The aspirator reduces the downstream pressure sensed by the duck valve when the discharge assembly is in the open position. This allows elongate pins to be moved through the duck valve with no backflow because the aspirator pressure is less than the pressure in the low pressure area from which the pins originate. Closure of the assembly causes the aspirator static pressure to force the flexible duck valve lip piece into a tightly sealed position also preventing backflow. The discharge assembly can be easily controlled using a single control valve which blocks the flow of aspirator gas and closes the pin passageway extending through the assembly.

  7. Differential pressure pin discharge apparatus

    DOEpatents

    Oakley, David J.

    1987-02-03

    Disclosed is a discharge assembly for allowing elongate pins to be discharged from an area of relatively low pressure to an area of relatively greater pressure. The discharge assembly includes a duck valve having a lip piece made of flexible material. The flexible lip piece responds to a fluctuating pressure created downstream by an aspirator. The aspirator reduces the downstream pressure sensed by the duck valve when the discharge assembly is in the open position. This allows elongate pins to be moved through the duck valve with no backflow because the aspirator pressure is less than the pressure in the low pressure area from which the pins originate. Closure of the assembly causes the aspirator static pressure to force the flexible duck valve lip piece into a tightly sealed position also preventing backflow. The discharge assembly can be easily controlled using a single control valve which blocks the flow of aspirator gas and closes the pin passageway extending through the assembly.

  8. Differential pressure pin discharge apparatus

    DOEpatents

    Oakley, D.J.

    1984-05-30

    Disclosed is a discharge assembly for allowing elongate pins to be discharged from an area of relatively low pressure to an area of relatively greater pressure. The discharge assembly includes a duck valve having a lip piece made of flexible material. The flexible lip piece responds to a fluctuating pressure created downstream by an aspirator. The aspirator reduces the downstream pressure sensed by the duck valve when the discharge assembly is in the open position. This allows elongate pins to be moved through the duck valve with no backflow because the aspirator pressure is less than the pressure in the low pressure area from which the pins originate. Closure of the assembly causes the aspirator static pressure to force the flexible duck valve lip piece into a tightly sealed position also preventing backflow. The discharge assembly can be easily controlled using a single control valve which blocks the flow of aspirator gas and closes the pins passageway extending through the assembly.

  9. Effect of Pin Tool Shape on Metal Flow During Friction Stir Welding

    NASA Technical Reports Server (NTRS)

    McClure, J. C.; Coronado, E.; Aloor, S.; Nowak, B.; Murr, L. M.; Nunes, Arthur C., Jr.; Munafo, Paul M. (Technical Monitor)

    2002-01-01

    It has been shown that metal moves behind the rotating Friction Stir Pin Tool in two separate currents or streams. One current, mostly on the advancing side, enters a zone of material that rotates with the pin tool for one or more revolutions and eventually is abandoned behind the pin tool in crescent-shaped pieces. The other current, largely on the retreating side of the pin tool is moved by a wiping process to the back of the pin tool and fills in between the pieces of the rotational zone that have been shed by the rotational zone. This process was studied by using a faying surface copper trace to clarify the metal flow. Welds were made with pin tools having various thread pitches. Decreasing the thread pitch causes the large scale top-to-bottorn flow to break up into multiple vortices along the pin and an unthreaded pin tool provides insufficient vertical motion for there to be a stable rotational zone and flow of material via the rotational zone is not possible leading to porosity on the advancing side of the weld.

  10. GCFR development status report

    SciTech Connect

    Not Available

    1980-05-01

    This report describes the major design features of the gas-cooled fast breeder reactor being developed in the United States principally at General Atomic Company. The report gives the general design strategy and highlights the design features of the reactor core and the nuclear steam supply components. It describes the design results on plant safety and licensing.

  11. PinBus Interface Design

    SciTech Connect

    Hammerstrom, Donald J.; Adgerson, Jewel D.; Sastry, Chellury; Pratt, Richard M.; Pratt, Robert G.

    2009-12-30

    On behalf of the U.S. Department of Energy, PNNL has explored and expanded upon a simple control interface that might have merit for the inexpensive communication of smart grid operational objectives (demand response, for example) to small electric end-use devices and appliances. The approach relies on bi-directional communication via the electrical voltage states of from one to eight shared interconnection pins. The name PinBus has been suggested and adopted for the proposed interface protocol. The protocol is defined through the presentation of state diagrams and the pins’ functional definitions. Both simulations and laboratory demonstrations are being conducted to demonstrate the elegance and power of the suggested approach. PinBus supports a very high degree of interoperability across its interfaces, allowing innumerable pairings of devices and communication protocols and supporting the practice of practically any smart grid use case.

  12. Prolyl isomerase Pin1 regulated signaling pathway revealed by Pin1 +/+ and Pin1 -/- mouse embryonic fibroblast cells.

    PubMed

    Huang, Guo-Liang; Qiu, Jin-Hua; Li, Bin-Bin; Wu, Jing-Jing; Lu, Yan; Liu, Xing-Yan; He, Zhiwei

    2013-10-01

    Pin1 (peptidylprolyl cis/trans isomerase, NIMA-interacting 1) plays a key role in a number of diseases including cancer and Alzheimer disease. Previous studies have identified a wide range of phosphoproteins as Pin1 substrates. Related pathways were analyzed separately. The aim of this study was to provide a comprehensive picture involving Pin1 regulation. A genome-wide mRNA expression microarray was carried out using the RNA isolation from Pin1 (+/+) and Pin1 (-/-) mouse embryonic fibroblast (MEF) cells. Signaling pathways regulated by Pin1 were analyzed with the utility of KEGG pathway and GO annotation. An expression pattern regulated by Pin1 was revealed. A total of 606 genes, 375 being up-regulated and 231 down-regulated, were differentially expressed when comparing Pin1 +/+ to Pin1 -/- MEF cells. Totally 48 pathways were shown to be regulated by Pin1 expression in KEGG pathway analysis. In the GO annotation system, 19 processes on biological processes, 15 processes on cellular components, and 18 processes on molecular functions were found to be in the regulation of Pin1 expression. Pathways related to immune system and cancer showed most significant association with Pin1 regulation. Pin1 is an important regulator in a wide range of signaling pathways that were related to immune system and cancer. PMID:23563987

  13. Thermoacoustic pin stacks. Summary report

    SciTech Connect

    Keolian, R.M.

    1994-07-06

    The construction and testing of a new stack geometry for thermoacoustic engines, called a pin stack, has been started. The stack is at the heart of a class of heat engines that use sound to deliver refrigeration, or use a temperature difference to generate sound. Calculations show that the pin stack should make useful improvements in engine efficiency. About 2000 wires will be hand sewn in a hexagonal lattice between the hot and cold heat exchangers in a sound source using low pressure neon gas between 300 K and 77 K. Thermoacoustics, Refrigeration, Acoustic source, Heat pump.

  14. ECOSYSTEM EFFECTS OF URBAN STREAM RESTORATION

    EPA Science Inventory

    <p>In general, the ecosystem function of a restored site will depend upon how degraded the site was prior to restoration and to what extent this was addressed in the restoration design. A stream whose primary impairment is severe water quality problems due to non-point source po...

  15. Cryogenically cooled detector pin mount

    SciTech Connect

    Hunt, Jr., William E; Chrisp, Michael P

    2014-06-03

    A focal plane assembly facilitates a molybdenum base plate being mounted to another plate made from aluminum. The molybdenum pin is an interference fit (press fit) in the aluminum base plate. An annular cut out area in the base plate forms two annular flexures.

  16. Heat/mass transfer and flow characteristics of pin fin cooling channels in turbine blades

    NASA Astrophysics Data System (ADS)

    Lau, S. C.; Saxena, A.

    Experiments studied the local heat/mass transfer distributions and pressure drops in pin fin channels that modeled internal cooling passages in gas turbine blades. Heat/mass transfer distributions were determined for a straight flow through a pin fin channel (H/D = 1.0, X/D = S/D = 2.5) and a flow through the pin fin channel with trailing edge flow ejection. The overall friction factor and local pressure drop results were obtained for various configurations and lengths of the trailing edge ejection holes. The results show that, when there is trailing edge flow ejection, the main flow stream turns toward the trailing edge ejection holes. The wake regions downstream of the pins and the regions affected by secondary flow shift toward the ejection holes. The local channel wall heat/mass transfer is generally high immediately upstream of a pin, in the wake region downstream of a pin, and in the regions affected by secondary flow. In the case with trailing edge flow ejection, the heat/mass transfer generally decreases in the radial direction as a result of the reducing radial mass flow rate. The overall friction is higher when the trailing edge ejection holes are longer and when they are configured such that more flow is forced further downstream in the pin fin channel before exiting through the ejection holes.

  17. Improved shock-detecting pin arrangement

    SciTech Connect

    Erskine, D.J.

    1996-05-01

    Shockwave speeds are often measured by comparing arrival times at the tips of electrical shorting pins in a hexagonal array over two elevations (called up and down). In the conventional arrangement, the center pin is solely responsible for measuring the curvature of the wavefront. Without this datum the shock speed cannot be precisely determined. In some experiments this pin fail frequently enough to be a problem. We report a simple rearrangement between up and down designated pins which eliminates the critical reliance on a single pin. {copyright} {ital 1996 American Institute of Physics.}

  18. Pinning control of chimera states

    NASA Astrophysics Data System (ADS)

    Gambuzza, Lucia Valentina; Frasca, Mattia

    2016-08-01

    The position of the coherent and incoherent domain of a chimera state in a ring of nonlocally coupled oscillators is strongly influenced by the initial conditions, making nontrivial the problem of confining them in a specific region of the structure. In this paper we propose the use of spatial pinning to induce a chimera state where the nodes belonging to one domain, either the coherent or the incoherent, are fixed by the control action. We design two different techniques according to the dynamics to be forced in the region of pinned nodes, and validate them on FitzHugh-Nagumo and Kuramoto oscillators. Furthermore, we introduce a suitable strategy to deal with the effects of finite size in small structures.

  19. Pinning synchronization of a mobile agent network

    NASA Astrophysics Data System (ADS)

    Wang, Lei; Sun, You-xian

    2009-11-01

    We investigate the problem of controlling a group of mobile agents in a plane in order to move them towards a desired orbit via pinning control, in which each agent is associated with a chaotic oscillator coupled with those of neighboring agents, and the pinning strategy is to have the common linear feedback acting on a small fraction of agents by random selection. We explore the effects of the pinning probability, feedback gains and agent density in the pinning synchronization of a mobile agent network under a fast-switching constraint, and perform numerical simulations for validation. In particular, we show that there exists a critical pinning density for network synchronization with an unbounded region: above the threshold, the dynamical network can be controlled by pinning; below it, anarchy prevails. And for the network with a single bounded synchronization region, pinning control has little effect as regards enhancing network synchronizability.

  20. Alignment Pins for Assembling and Disassembling Structures

    NASA Technical Reports Server (NTRS)

    Campbell, Oliver C.

    2008-01-01

    Simple, easy-to-use, highly effective tooling has been devised for maintaining alignment of bolt holes in mating structures during assembly and disassembly of the structures. The tooling was originally used during removal of a body flap from the space shuttle Atlantis, in which misalignments during removal of the last few bolts could cause the bolts to bind in their holes. By suitably modifying the dimensions of the tooling components, the basic design of the tooling can readily be adapted to other structures that must be maintained in alignment. The tooling includes tapered, internally threaded alignment pins designed to fit in the bolt holes in one of the mating structures, plus a draw bolt and a cup that are used to install or remove each alignment pin. In preparation for disassembly of two mating structures, external supports are provided to prevent unintended movement of the structures. During disassembly of the structures, as each bolt that joins the structures is removed, an alignment pin is installed in its place. Once all the bolts have been removed and replaced with pins, the pins maintain alignment as the structures are gently pushed or pulled apart on the supports. In assembling the two structures, one reverses the procedure described above: pins are installed in the bolt holes, the structures are pulled or pushed together on the supports, then the pins are removed and replaced with bolts. The figure depicts the tooling and its use. To install an alignment pin in a bolt hole in a structural panel, the tapered end of the pin is inserted from one side of the panel, the cup is placed over the pin on the opposite side of the panel, the draw bolt is inserted through the cup and threaded into the pin, the draw bolt is tightened to pull the pin until the pin is seated firmly in the hole, then the draw bolt and cup are removed, leaving the pin in place. To remove an alignment pin, the cup is placed over the pin on the first-mentioned side of the panel, the draw

  1. CONNECTICUT STREAMS

    EPA Science Inventory

    This is a 1:24,000-scale datalayer of named streams in Connecticut. It includes two Shapefiles with line and polygon features. Both Shapefiles should be used together. The polygon shapefile fills in open water streams such as the Connecticut River as well as Long Island Sound. T...

  2. Stream Processors

    NASA Astrophysics Data System (ADS)

    Erez, Mattan; Dally, William J.

    Stream processors, like other multi core architectures partition their functional units and storage into multiple processing elements. In contrast to typical architectures, which contain symmetric general-purpose cores and a cache hierarchy, stream processors have a significantly leaner design. Stream processors are specifically designed for the stream execution model, in which applications have large amounts of explicit parallel computation, structured and predictable control, and memory accesses that can be performed at a coarse granularity. Applications in the streaming model are expressed in a gather-compute-scatter form, yielding programs with explicit control over transferring data to and from on-chip memory. Relying on these characteristics, which are common to many media processing and scientific computing applications, stream architectures redefine the boundary between software and hardware responsibilities with software bearing much of the complexity required to manage concurrency, locality, and latency tolerance. Thus, stream processors have minimal control consisting of fetching medium- and coarse-grained instructions and executing them directly on the many ALUs. Moreover, the on-chip storage hierarchy of stream processors is under explicit software control, as is all communication, eliminating the need for complex reactive hardware mechanisms.

  3. Pin Wire Coating Trip Report

    SciTech Connect

    Spellman, G P

    2004-03-18

    A meeting to discuss the current pin wire coating problems was held at the Reynolds plant in Los Angeles on 2MAR04. The attendance list for Reynolds personnel is attached. there was an initial presentation which gave a brief history and the current status of pin wire coating at Reynolds. There was a presentation by Lori Primus on the requirements and issues for the coating. There was a presentation by Jim Smith of LANL on the chemistry and to some extent process development done to date. There was a long session covering what steps should be taken in the short term and, to a lesser extent, the long term. The coating currently being used is a blend of two polymers, polyethersulfone and polyparabanic acid (PPA) and some TiO2 filler. This system was accepted and put into production when the pin wire coating was outsourced to another company in 1974. When that company no longer was interested, the wire coating was brought in-house to Reynolds. At that time polyparabanic acid was actually a commercial product available from Exxon under the trade name Tradlon. However, it appears that the material used at Reynolds was synthesized locally. Also, it appears that a single large batch was synthesized in that time period and used up to 1997 when the supply ran out. The reason for the inclusion of TiO2 is not known although it does act as a rheological thickener. However, a more controlled thickening can be obtained with materials such as fumed silica. This material would have less likelihood of causing point imperfections in the coatings. Also, the mixing technique being used for all stages of the process is a relatively low shear ball mill process and the author recommends a high shear process such as a three roll paint mill, at least for the final mixing. Since solvent is added to the powder at Reynolds, it may be that they need to have the paint mill there.

  4. Tool Blunts Cotter Pin Legs for Safety

    NASA Technical Reports Server (NTRS)

    Stein, J. A.; Helble, D. R.

    1982-01-01

    Jaws on new insertion tool contain upset point and anvil. Point forces cotter-pin legs into loop as it engages anvil. Cotter pin before insertion consists of loop and straight shaft composed of two legs welded together as tips. After insertion, welded legs have been shaped into loop. Tool used to prevent bent loose ends of cotter pins from scratching workers' fingers or cutting and entangling wires.

  5. Magnetic pinning in superconductor-ferromagnet multilayers

    SciTech Connect

    Bulaevskii, L. N.; Chudnovsky, E. M.; Maley, M. P.

    2000-05-01

    We argue that superconductor/ferromagnet multilayers of nanoscale period should exhibit strong pinning of vortices by the magnetic domain structure in magnetic fields below the coercive field when ferromagnetic layers exhibit strong perpendicular magnetic anisotropy. The estimated maximum magnetic pinning energy for single vortex in such a system is about 100 times larger than the pinning energy by columnar defects. This pinning energy may provide critical currents as high as 10{sup 6}-10{sup 7} A/cm{sup 2} at high temperatures (but not very close to T{sub c}) at least in magnetic fields below 0.1 T. (c) 2000 American Institute of Physics.

  6. Improved shock-detection pin arrangement

    SciTech Connect

    Erskine, D.J.

    1995-08-01

    Shockwave speeds are often measured by comparing arrival times at the tips of electrical shorting pins in a hexagonal array over two elevations (called up and down). In the conventional arrangement, the center pin is solely responsible for measuring the curvature of the wavefront. Without this datum the shock speed cannot be precisely determined. In some experiments this pin fail frequently enough to be a problem. We report a simple rearrangement between up and down designated pins which eliminates the critical reliance on a single.

  7. Piezoelectric Pins for Use as Dust Detectors

    NASA Astrophysics Data System (ADS)

    Manning, H. L. K.; Campbell, I. H.; Nelson, K. A.; Yager, J. R.

    2002-09-01

    Piezoelectric pins are devices currently used in a number of applications including detecting elementary particle beams, monitoring volcanoes, and detecting high-speed micro-sized particles. These pins provide a means of studying ejecta from cratering processes in the laboratory and offer a potential lightweight, low power, flight dust detector. Using the hypervelocity dust particle accelerator at Concordia College in Moorhead, Minnesota, we have investigated the transient charge generated by piezoelectric pins impacted by dust particles. Carbonyl iron dust particles of 0.5-5 micrometer diameter having speeds ranging from 1-5 km/sec impacted the pins. The DC-100 MHz pin response was recorded and analyzed. The transient pin response to a single particle consists of many charge pulses of alternating sign (less than 10 ns in duration) separated by the pressure wave propagation time across the crystal (typically 100 ns). The charge produced by the pin changes sign when the pressure waves in the piezoelectric crystal reflect off of the metal electrodes. The magnitude of the pin response as a function of the impacting particle properties is presented and discussed. Pins using both polycrystalline PZT and single crystal LiNbO3 as the piezoelectric material were studied. This work is supported at Concordia College by the Minnesota Space Grant Consortium.

  8. Heat Exchanger With Internal Pin Elements

    DOEpatents

    Gerstmann, Joseph; Hannon, Charles L.

    2004-01-13

    A heat exchanger/heater comprising a tubular member having a fluid inlet end, a fluid outlet end and plurality of pins secured to the interior wall of the tube. Various embodiments additionally comprise a blocking member disposed concentrically inside the pins, such as a core plug or a baffle array. Also disclosed is a vapor generator employing an internally pinned tube, and a fluid-heater/heat-exchanger utilizing an outer jacket tube and fluid-side baffle elements, as well as methods for heating a fluid using an internally pinned tube.

  9. Fabrication of FFTF fuel pin wire wrap

    SciTech Connect

    Epperson, E.M.

    1980-06-01

    Lateral spacing between FFTF fuel pins is required to provide a passageway for the sodium coolant to flow over each pin to remove heat generated by the fission process. This spacing is provided by wrapping each fuel pin with type 316 stainless steel wire. This wire has a 1.435mm (0.0565 in.) to 1.448mm (0.0570 in.) diameter, contains 17 +- 2% cold work and was fabricated and tested to exacting RDT Standards. About 500 kg (1100 lbs) or 39 Km (24 miles) of fuel pin wrap wire is used in each core loading. Fabrication procedures and quality assurance tests are described.

  10. Update on PIN or Signature

    NASA Astrophysics Data System (ADS)

    Matyas, Vashek

    We promised a year back some data on the experiment that we ran with chip and PIN. If you recall, it was the first phase that we reported on here last year, where we used the University bookstore, and two PIN pads, one with very solid privacy shielding, the other one without any. We ran 17 people through the first one, 15 people through the second one, and we also had the students do, about half of them forging the signature, half of them signing their own signature, on the back of the card that is used for purchasing books, or whatever.We had a second phase of the experiment, after long negotiations, and very complicated logistics, with a supermarket in Brno where we were able to do anything that we wanted through the experiment for five hours on the floor, with only the supermarket manager, the head of security, and the camera operators knowing about the experiment. So the shop assistants, the ground floor security, everybody basically on the floor, did not know about the experiment. That was one of the reasons why the supermarket, or management, agreed to take part, they wanted to control their own internal security procedures.

  11. Replacement of split-pin assemblies in nuclear reactors

    SciTech Connect

    Nee, J.D.; Green, R.A.

    1989-12-12

    This patent describes a pin-insertion/torque tool for the replacement of old split-pin assemblies. Each of the new split-pin assemblies including a new split-pin having times and a new nut for securing the new split pin in the guide tube, a new nut being inserted in the guide tube in position to receive a split pin. The the pin-insertion/torque tool including a blade means for engaging a new split pin with the blade with the tines of the new split pins straddling the blade, means, connected to the blade, for advancing the split-pin into the guide tube into threading engagement with the new nut positioned to receive a new split pin and means, to be connected to the nut for securing the new nut onto the new split pin while the split pin is engaged by the blade.

  12. Failure Analysis of Electrical Pin Connectors

    NASA Technical Reports Server (NTRS)

    Newman, John A.; Baughman, James M.; Smith, Stephen W.; Herath, Jeffrey A.

    2008-01-01

    A study was initiated to determine the root cause of failure for circuit board electrical connection pins that failed during vibRatory testing. The circuit board is part of an unmanned space probe, and the vibratory testing was performed to ensure component survival of launch loading conditions. The results of this study show that the pins failed as a result of fatigue loading.

  13. Pin1 as an anticancer drug target.

    PubMed

    Xu, Guoyan G; Etzkorn, Felicia A

    2009-09-01

    Pin1 specifically catalyzes the cis/trans isomerization of phospho-Ser/Thr-Pro bonds and plays an important role in many cellular events through the effects of conformational change on the function of its biological substrates, including cell division cycle 25 C (Cdc25C), c-Jun and p53. Pin1 is overexpressed in many human cancer tissues, including breast, prostate and lung cancer. Its expression correlates with cyclin D1 levels, which contribute to cell transformation. Overexpression of Pin1 promotes tumor growth, while inhibition of Pin1 causes tumor cell apoptosis. Pin1 plays an important role in oncogenesis and therefore may serve as an effective anticancer target. Many inhibitors of Pin1 have been discovered, including several classes of designed inhibitors (alkene isosteres, reduced amides, indanyl ketones) and natural products (juglone, pepticinnamin E analogues, PiB and its derivatives obtained from a library screen). Pin1 inhibitors could be used as a novel type of anticancer drug by blocking cell cycle progression. Therefore, Pin1 represents a new diagnostic and therapeutic anticancer drug target. PMID:19890497

  14. Pinning impulsive control algorithms for complex network

    SciTech Connect

    Sun, Wen; Lü, Jinhu; Chen, Shihua; Yu, Xinghuo

    2014-03-15

    In this paper, we further investigate the synchronization of complex dynamical network via pinning control in which a selection of nodes are controlled at discrete times. Different from most existing work, the pinning control algorithms utilize only the impulsive signals at discrete time instants, which may greatly improve the communication channel efficiency and reduce control cost. Two classes of algorithms are designed, one for strongly connected complex network and another for non-strongly connected complex network. It is suggested that in the strongly connected network with suitable coupling strength, a single controller at any one of the network's nodes can always pin the network to its homogeneous solution. In the non-strongly connected case, the location and minimum number of nodes needed to pin the network are determined by the Frobenius normal form of the coupling matrix. In addition, the coupling matrix is not necessarily symmetric or irreducible. Illustrative examples are then given to validate the proposed pinning impulsive control algorithms.

  15. Pin-Retraction Mechanism On Quick-Release Cover

    NASA Technical Reports Server (NTRS)

    Macmartin, Malcolm

    1994-01-01

    Quick-release cover includes pin-retraction mechanism releasing cover quickly from lower of two sets of pin connections holding cover. Cover released at top by pulling lever as described in "Lever-Arm Pin Puller" (NPO-18788). Removal of cover begins when technician or robot pulls upper-pin-release lever. Cover swings downward until tabs on lower pins are pulled through slots in their receptacles. Lower pins are then free.

  16. The Mean-Field Flux Pinning Theory

    NASA Astrophysics Data System (ADS)

    Stejic, George

    We develop the Mean-Field Flux Pinning Theory, designed to model the flux line lattice (FLL) as it interacts with itself, the flux pinning centers and the geometry of the superconductor. Like other mean-field theories, the mean-field flux pinning theory does not attempt to model the FLL completely. Instead, it utilizes a simplified model for the FLL, termed the mean-field FLL, in which the FLL is modelled as a continuous vector field rather than as discrete fluxons as in other theories. By so doing, the interactions of the FLL are greatly simplified and more easily modelled. One application of the mean-field flux pinning theory is to predict J_{c} from microstructural data, which we use to determine the optimal Nb-Ti microstructures with (1) alpha -Ti pinning centers and (2) Nb pinning centers. The microstructure is modelled on a grid in which the local values of T_{c} and kappa reflect the spatial distribution of the pinning centers and the superconductor. Using this model, we solve the G-L equations and calculate the pinning potential defined as the vortex free energy as a function of position. We conclude that the ideal Nb-Ti microstructure with alpha-Ti pinning centers would require 40 volume percent of alpha -Ti and have 6nm thick pinning centers. In the Nb pinning center case, the ideal microstructure requires 50 volume percent of Nb and would have 6nm pinning centers. Another application for the mean-field flux pinning theory is to model the FLL as it interacts with the penetrating magnetic fields within lambda of the superconducting surface. Using this theory, we study the effects of sample geometry on the FLL and J _{c} for the thin film geometry. We find that the FLL becomes increasingly distorted as the film thickness is reduced and that J_{c } increases sharply for dimensions less that lambda. These predictions are experimentally evaluated in Nb-Ti thin films. Our results show that J_{c} values as high as 1/3 of J_{d} and a strong orientational

  17. Pinning Loss Power Density in Superconductors

    NASA Astrophysics Data System (ADS)

    Matsushita, Teruo

    2015-03-01

    The pinning loss power density is theoretically derived based on the resistive energy dissipation when the flux lines are driven by the Lorentz force in a superconductor. The obtained loss power density does not depend on the viscosity or flow resistivity, but is proportional to the pinning force density only, and it possesses the nature of hysteresis loss, as commonly measured in experiments. These features are predicted by the critical state model, which was recently proved theoretically. The obtained pinning force density is consistent with the prediction of the coherent potential approximation theory, a kind of statistical summation theory, for flux pinning. Thus, the irreversible properties associated with the flux pinning can be comprehensively described by these flux pinning theories. The irreversible flux pinning in the superconductor is compared with similar irreversible phenomena such as the motion of magnetic domain walls in ferromagnetic materials and the friction in mechanical systems. The possibility is also discussed for a general theoretical description of these irreversible phenomena in which the hysteresis loss occurs.

  18. Asymmetric gibberellin signaling regulates vacuolar trafficking of PIN auxin transporters during root gravitropism.

    PubMed

    Löfke, Christian; Zwiewka, Marta; Heilmann, Ingo; Van Montagu, Marc C E; Teichmann, Thomas; Friml, Jirí

    2013-02-26

    Gravitropic bending of plant organs is mediated by an asymmetric signaling of the plant hormone auxin between the upper and lower side of the respective organ. Here, we show that also another plant hormone, gibberellic acid (GA), shows asymmetric action during gravitropic responses. Immunodetection using an antibody against GA and monitoring GA signaling output by downstream degradation of DELLA proteins revealed an asymmetric GA distribution and response with the maximum at the lower side of gravistimulated roots. Genetic or pharmacological manipulation of GA levels or response affects gravity-mediated auxin redistribution and root bending response. The higher GA levels at the lower side of the root correlate with increased amounts of PIN-FORMED2 (PIN2) auxin transporter at the plasma membrane. The observed increase in PIN2 stability is caused by a specific GA effect on trafficking of PIN proteins to lytic vacuoles that presumably occurs downstream of brefeldin A-sensitive endosomes. Our results suggest that asymmetric auxin distribution instructive for gravity-induced differential growth is consolidated by the asymmetric action of GA that stabilizes the PIN-dependent auxin stream along the lower side of gravistimulated roots. PMID:23391733

  19. Stream Studies.

    ERIC Educational Resources Information Center

    Hamilton City Board of Education (Ontario).

    This manual provides teachers with some knowledge of ecological study methods and techniques used in collecting data when plants and animals are studied in the field. Most activities deal with the interrelatedness of plant and animal life to the structure and characteristics of a stream and pond. Also included in this unit plan designed for the…

  20. Stream Studies.

    ERIC Educational Resources Information Center

    Stein, Scott

    1997-01-01

    Outlines a science curriculum reform effort aimed at enabling students to collect original data concerning an environmental parameter such as water quality on a yearly basis. Students track the overall health of the stream by analyzing both biotic and abiotic factors. (DDR)

  1. Electroanalytical devices with pins and thread.

    PubMed

    Glavan, Ana C; Ainla, Alar; Hamedi, Mahiar M; Fernández-Abedul, M Teresa; Whitesides, George M

    2016-01-01

    This work describes the adaptive use of conventional stainless steel pins-used in unmodified form or coated with carbon paste-as working, counter, and quasi-reference electrodes in electrochemical devices fabricated using cotton thread or embossed omniphobic R(F) paper to contain the electrolyte and sample. For some applications, these pin electrodes may be easier to modify and use than printed electrodes, and their position and orientation can be changed as needed. Electroanalytical devices capable of multiplex analysis (thread-based arrays or 96-well plates) were easily fabricated using pins as electrodes in either thread or omniphobic R(F) paper. PMID:26549661

  2. Using Pin as a Memory Reference Generator for Multiprocessor Simulation

    SciTech Connect

    McCurdy, C

    2005-10-22

    In this paper we describe how we have used Pin to generate a multithreaded reference stream for simulation of a multiprocessor on a uniprocessor. We have taken special care to model as accurately as possible the effects of cache coherence protocol state, and lock and barrier synchronization on the performance of multithreaded applications running on multiprocessor hardware. We first describe a simplified version of the algorithm, which uses semaphores to synchronize instrumented application threads and the simulator on every memory reference. We then describe modifications to that algorithm to model the microarchitectural features of the Itanium2 that affect the timing of memory reference issue. An experimental evaluation determines that while cycle-accurate multithreaded simulation is possible using our approach, the use of semaphores has a negative impact on the performance of the simulator.

  3. The Unbearable Lightness of PIN Cracking

    NASA Astrophysics Data System (ADS)

    Berkman, Omer; Ostrovsky, Odelia Moshe

    We describe new attacks on the financial PIN processing API. The attacks apply to switches as well as to verification facilities. The attacks are extremely severe allowing an attacker to expose customer PINs by executing only one or two API calls per exposed PIN. One of the attacks uses only the translate function which is a required function in every switch. The other attacks abuse functions that are used to allow customers to select their PINs online. Some of the attacks can be applied in switches even though the attacked functions require issuer's keys which do not exist in a switch. This is particularly disturbing as it was widely believed that functions requiring issuer's keys cannot do any harm if the respective keys are unavailable.

  4. The actuated latch pin and its development

    NASA Technical Reports Server (NTRS)

    Lawlor, P. J.

    1980-01-01

    An actuated latch pin developed to meet the need for a reusable locking device is described. The unit can function as a pin puller or as a pin pusher latch. Initial prototype testing demonstrated the feasibility of the device with the unit being driven from a 28 V dc supply and using 15 W to drive a 12 mm diameter pin through a stroke of 10 mm with a side load of 100 N in 120 ms. High wear rates with a MOS2 lubrication on the ballscrew and angular contact bearings have necessitated the reduction in the duty cycle from 1000 cycles in air and vacuum to 100 in air and 1000 in vacuum.

  5. Quick-Release Pin With Lever Action

    NASA Technical Reports Server (NTRS)

    Trevino, Robert C.

    1995-01-01

    Lever-action quick-release pin operated more easily. Mechanism operated with gloved hand. In modified version, lever added to handle to facilitate actuation. Lever action reduces actuation force. Lever-action pin operated by squeezing on any point of moveable ends of lever and handle together between thumb and forefinger or by simply grasping and squeezing handle and lever with entire hand in more natural grasp.

  6. IMp: The customizable LEGO® Pinned Insect Manipulator

    PubMed Central

    Dupont, Steen; Price, Benjamin; Blagoderov, Vladimir

    2015-01-01

    Abstract We present a pinned insect manipulator (IMp) constructed of LEGO® building bricks with two axes of movement and two axes of rotation. In addition we present three variants of the IMp to emphasise the modular design, which facilitates resizing to meet the full range of pinned insect specimens, is fully customizable, collapsible, affordable and does not require specialist tools or knowledge to assemble. PMID:25685035

  7. Performance measurements of hybrid PIN diode arrays

    SciTech Connect

    Shapiro, S.L. ); Arens, J.F.; Jernigan, J.G. . Space Sciences Lab.); Kramer, G. ); Collins, T.; Worley, S. ); Wilburn, C.D. ); Skubic, P. )

    1990-10-01

    We report the successful development of hybrid PIN diode arrays and a series of room-temperature measurements in a high-energy pion beam at FNAL. A PMOS VLSI 256 {times} 256 readout array having 30 {mu}m square pixels was indium-bump bonded to a mating PIN diode detector array. Preliminary measurements on the resulting hybrid show excellent signal-to-noise at room temperature. 3 refs., 5 figs.

  8. Investigating Dynamic Interdomain Allostery in Pin1

    PubMed Central

    Peng, Jeffrey W.

    2015-01-01

    Signaling proteins often sequester complementary functional sites in separate domains. How do the different domains communicate with one another? An attractive system to address this question is the mitotic regulator, human Pin1 (Lu et al. 1996). Pin-1 consists of two tethered domains: a WW domain for substrate binding, and a catalytic domain for peptidyl-prolyl isomerase (PPIase) activity. Pin1 accelerates the cis-trans isomerization of phospho-Ser/Thr-Pro (pS/T-P) motifs within proteins regulating the cell cycle and neuronal development. The early x-ray (Ranganathan et al. 1997; Verdecia et al. 2000) and solution NMR studies (Bayer et al. 2003; Jacobs et al. 2003) of Pin1 indicated inter- and intradomain motion. We became interested in exploring how such motions might affect interdomain communication, using NMR. Our accumulated results indicate substrate binding to Pin1 WW domain changes the intra/inter domain mobility, thereby altering substrate activity in the distal PPIase domain catalytic site. Thus, Pin1 shows evidence of dynamic allostery, in the sense of Cooper and Dryden (Cooper and Dryden 1984). We highlight our results supporting this conclusion, and summarize them via a simple speculative model of conformational selection. PMID:26495045

  9. Self-locking double retention redundant pull pin release

    NASA Technical Reports Server (NTRS)

    Killgrove, Thomas O. (Inventor)

    1987-01-01

    A double-retention redundant pull pin release system is disclosed. The system responds to a single pull during an intentional release operation. A spiral-threaded main pin is seated in a mating bore in a housing, which main pin has a flange fastened thereon at the part of the main pin which is exterior to the housing. Accidental release tends to rotate the main pin. A secondary pin passes through a slightly oversized opening in the flange and is seated in a second bore in the housing. The pins counteract against one another to prevent accidental release. A frictional lock is shared between the main and secondary pins to enhance further locking of the system. The secondary pin, in response to a first pull, is fully retracted from its bore and flange hole. Thereafter the pull causes the main pin to rotate free of the housing to release, for example, a parachute mechanism.

  10. Whole-Pin Furnace system: An experimental facility for studying irradiated fuel pin behavior under potential reactor accident conditions

    SciTech Connect

    Liu, Y.Y.; Tsai, H.C.; Donahue, D.A.; Pushis, D.O.; Savoie, F.E.; Holland, J.W.; Wright, A.E.; August, C.; Bailey, J.L.; Patterson, D.R.

    1990-05-01

    The whole-pin furnace system is a new in-cell experimental facility constructed to investigate how irradiated fuel pins may fail under potential reactor accident conditions. Extensive checkouts have demonstrated excellent performance in remote operation, temperature control, pin breach detection, and fission gas handling. The system is currently being used in testing of EBIR-II-irradiated Integral Fast Reactor (IFR) metal fuel pins; future testing will include EBR-II-irradiated mixed-oxide fuel pins. 7 refs., 4 figs.

  11. The Maize PIN Gene Family of Auxin Transporters.

    PubMed

    Forestan, Cristian; Farinati, Silvia; Varotto, Serena

    2012-01-01

    Auxin is a key regulator of plant development and its differential distribution in plant tissues, established by a polar cell to cell transport, can trigger a wide range of developmental processes. A few members of the two families of auxin efflux transport proteins, PIN-formed (PIN) and P-glycoprotein (ABCB/PGP), have so far been characterized in maize. Nine new Zea mays auxin efflux carriers PIN family members and two maize PIN-like genes have now been identified. Four members of PIN1 (named ZmPIN1a-d) cluster, one gene homologous to AtPIN2 (ZmPIN2), three orthologs of PIN5 (ZmPIN5a-c), one gene paired with AtPIN8 (ZmPIN8), and three monocot-specific PINs (ZmPIN9, ZmPIN10a, and ZmPIN10b) were cloned and the phylogenetic relationships between early-land plants, monocots, and eudicots PIN proteins investigated, including the new maize PIN proteins. Tissue-specific expression patterns of the 12 maize PIN genes, 2 PIN-like genes and ZmABCB1, an ABCB auxin efflux carrier, were analyzed together with protein localization and auxin accumulation patterns in normal conditions and in response to drug applications. ZmPIN gene transcripts have overlapping expression domains in the root apex, during male and female inflorescence differentiation and kernel development. However, some PIN family members have specific tissue localization: ZmPIN1d transcript marks the L1 layer of the shoot apical meristem and inflorescence meristem during the flowering transition and the monocot-specific ZmPIN9 is expressed in the root endodermis and pericycle. The phylogenetic and gene structure analyses together with the expression pattern of the ZmPIN gene family indicate that subfunctionalization of some maize PINs can be associated to the differentiation and development of monocot-specific organs and tissues and might have occurred after the divergence between dicots and monocots. PMID:22639639

  12. Ratchet effect in a conformal pinning array

    NASA Astrophysics Data System (ADS)

    Janko, Boldizsar; Ray, Dipanjan; Olson Reichhardt, Cynthia; Reichhardt, Charles

    2014-03-01

    Pinning arrays where the pinning sites are located at the vertices of a conformally transformed hexagonal lattice, also known as conformal pinning arrays (CPA), have recently been shown to greatly enhance the critical current of type-II superconductors both in simulation and in experiment. Here we show using molecular dynamics simulations that the differing flux-flow resistance of the CPA in the forward and reverse directions causes it to function as a highly effective vortex ratchet. We drive the vortices using an applied external ac current, and we find that the resulting dc output voltage for the CPA ratchet is larger than that for a random pinning array with a pinning gradient by up to an order of magnitude. The enhancement is robust over a wide range of vortex densities, temperatures, and ac drive amplitudes and frequencies. D. Ray et al, Phys. Rev. Lett. 110, 267001 (2013); Y. L. Wang et al, Phys. Rev. B 87, 220501(R) (2013); S. Guenon et al, Appl. Phys. Lett. 102, 252602 (2013).

  13. De-pinning of disordered bosonic chains

    NASA Astrophysics Data System (ADS)

    Vogt, N.; Cole, J. H.; Shnirman, A.

    2016-05-01

    We consider onset of transport (de-pinning) in one-dimensional bosonic chains with a repulsive boson–boson interaction that decays exponentially on large length-scales. Our study is relevant for (i) de-pinning of Cooper-pairs in Josephson junction arrays; (ii) de-pinning of magnetic flux quanta in quantum-phase-slip ladders, i.e. arrays of superconducting wires in a ladder-configuration that allow for the coherent tunneling of flux quanta. In the low-frequency, long wave-length regime these chains can be mapped onto an effective model of a one-dimensional elastic field in a disordered potential. The standard de-pinning theories address infinitely long systems in two limiting cases: (a) of uncorrelated disorder (zero correlation length); (b) of long range power-law correlated disorder (infinite correlation length). In this paper we study numerically chains of finite length in the intermediate case of long but finite disorder correlation length. This regime is of relevance for, e.g., the experimental systems mentioned above. We study the interplay of three length scales: the system length, the interaction range, the correlation length of disorder. In particular, we observe the crossover between the solitonic onset of transport in arrays shorter than the disorder correlation length to onset of transport by de-pinning for longer arrays.

  14. Statistics of dislocation pinning at localized obstacles

    NASA Astrophysics Data System (ADS)

    Dutta, A.; Bhattacharya, M.; Barat, P.

    2014-10-01

    Pinning of dislocations at nanosized obstacles like precipitates, voids, and bubbles is a crucial mechanism in the context of phenomena like hardening and creep. The interaction between such an obstacle and a dislocation is often studied at fundamental level by means of analytical tools, atomistic simulations, and finite element methods. Nevertheless, the information extracted from such studies cannot be utilized to its maximum extent on account of insufficient information about the underlying statistics of this process comprising a large number of dislocations and obstacles in a system. Here, we propose a new statistical approach, where the statistics of pinning of dislocations by idealized spherical obstacles is explored by taking into account the generalized size-distribution of the obstacles along with the dislocation density within a three-dimensional framework. Starting with a minimal set of material parameters, the framework employs the method of geometrical statistics with a few simple assumptions compatible with the real physical scenario. The application of this approach, in combination with the knowledge of fundamental dislocation-obstacle interactions, has successfully been demonstrated for dislocation pinning at nanovoids in neutron irradiated type 316-stainless steel in regard to the non-conservative motion of dislocations. An interesting phenomenon of transition from rare pinning to multiple pinning regimes with increasing irradiation temperature is revealed.

  15. Statistics of dislocation pinning at localized obstacles

    SciTech Connect

    Dutta, A.; Bhattacharya, M. Barat, P.

    2014-10-14

    Pinning of dislocations at nanosized obstacles like precipitates, voids, and bubbles is a crucial mechanism in the context of phenomena like hardening and creep. The interaction between such an obstacle and a dislocation is often studied at fundamental level by means of analytical tools, atomistic simulations, and finite element methods. Nevertheless, the information extracted from such studies cannot be utilized to its maximum extent on account of insufficient information about the underlying statistics of this process comprising a large number of dislocations and obstacles in a system. Here, we propose a new statistical approach, where the statistics of pinning of dislocations by idealized spherical obstacles is explored by taking into account the generalized size-distribution of the obstacles along with the dislocation density within a three-dimensional framework. Starting with a minimal set of material parameters, the framework employs the method of geometrical statistics with a few simple assumptions compatible with the real physical scenario. The application of this approach, in combination with the knowledge of fundamental dislocation-obstacle interactions, has successfully been demonstrated for dislocation pinning at nanovoids in neutron irradiated type 316-stainless steel in regard to the non-conservative motion of dislocations. An interesting phenomenon of transition from rare pinning to multiple pinning regimes with increasing irradiation temperature is revealed.

  16. A double tuned rail damper—increased damping at the two first pinned-pinned frequencies

    NASA Astrophysics Data System (ADS)

    Maes, J.; Sol, H.

    2003-10-01

    Railway-induced vibrations are a growing matter of environmental concern. The rapid development of transportation, the increase of vehicle speeds and vehicle weights have resulted in higher vibration levels. In the meantime vibrations that were tolerated in the past are now considered to be a nuisance. Numerous solutions have been proposed to remedy these problems. The majority only acts on a specific part of the dynamic behaviour of the track. This paper presents a possible solution to reduce the noise generated by the 'pinned-pinned' frequencies. Pinned-pinned frequencies correspond with standing waves whose nodes are positioned exactly at the sleeper supports. The two first pinned-pinned frequencies are situated approximately at 950 and 2200 Hz (UIC60-rail and sleeper spacing of 0.60 m). To attenuate these vibrations, the Department of MEMC at the VUB has developed a dynamic vibration absorber called the Double Tuned Rail Damper (DTRD). The DTRD is mounted between two sleepers on the rail and is powered by the motion of the rail. The DTRD consists of two major parts: a steel plate which is connected to the rail with an interface of an elastic layer, and a rubber mass. The two first resonance frequencies of the steel plate coincide with the targeted pinned-pinned frequencies of the rail. The rubber mass acts as a motion controller and energy absorber. Measurements at a test track of the French railway company (SNCF) have shown considerable attenuation of the envisaged pinned-pinned frequencies. The attenuation rate surpasses 5 dB/m at certain frequency bands.

  17. A division in PIN-medicated patterning during lateral organ initiation in grasses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Using phlyogenic and gene synteny analysis we identified an angiosperm PIN clade sister to PIN1, here termed SISter-of-PIN1 (soPIN1), which is present in all sampled angiosperms except for Brassicaceae. Additionally, we identified a conserved duplication of PIN1 in the grasses: PIN1a and PIN1b. In...

  18. Transportation of pinned charge density waves

    NASA Astrophysics Data System (ADS)

    Koo, Je Huan; Jeong, Jae Yoon; Cho, Guangsup

    2009-01-01

    We investigated the transport of pinned charge density waves (CDWs) that is observed in low dimensional materials. We treated pinned CDWs as moving CDWs that were confined within a typical quantum well amongst the many different types where pinning occurs at the barrier. We calculated the current flowing out of the quantum well by confined CDWs. The calculated conductivity is in good correspondence with experimental data in TTF-TCNQ, where the measured Fröhlich-Peierls temperature is 60 K much higher than the theoretical value of 20 K. The voltage dependence of the conductivity was calculated, where this is easily transformed into the dependence of electric field. The magnetic susceptibility was also calculated with a similar trend of experimental data. The susceptibility is a diamagnetic contribution by CDWs in addition to the constant background Pauli paramagnetic part.

  19. PINS Testing and Modification for Explosive Identification

    SciTech Connect

    E.H. Seabury; A.J. Caffrey

    2011-09-01

    The INL's Portable Isotopic Neutron Spectroscopy System (PINS)1 non-intrusively identifies the chemical fill of munitions and sealed containers. PINS is used routinely by the U.S. Army, the Defense Threat Reduction Agency, and foreign military units to determine the contents of munitions and other containers suspected to contain explosives, smoke-generating chemicals, and chemical warfare agents such as mustard and nerve gas. The objects assayed with PINS range from softball-sized M139 chemical bomblets to 200 gallon DOT 500X ton containers. INL had previously examined2 the feasibility of using a similar system for the identification of explosives, and based on this proof-of-principle test, the development of a dedicated system for the identification of explosives in an improvised nuclear device appears entirely feasible. INL has been tasked by NNSA NA-42 Render Safe Research and Development with the development of such a system.

  20. Flows in Pinned Arrays Simulating Brush Seals

    NASA Technical Reports Server (NTRS)

    Hendricks, R.C.; Kudriavtsev, V. V.; Braun, M. J.; Athavale, M. M.

    1996-01-01

    Flows through idealized pin arrays were investigated using an unstructured grid finite difference model and the simplified Ergun model to predict leakage flows and pressure drops in brush seals. The models are in good agreement in the laminar region with departures in the laminar-turbulent transition region defined by the simplified Ergun model. No local disturbances in the velocity or pressure fields, symptomatic of turbulence were found in the numerical results. The simplified model failed to predict the pressure drop of a 32-pin anisotropic array. Transitional and anisotropic behavior requires

  1. Rotary pin-in-maze discriminator

    DOEpatents

    Benavides, Gilbert L.

    1997-01-01

    A discriminator apparatus and method that discriminates between a unique signal and any other (incorrect) signal. The unique signal is a sequence of events; each event can assume one of two possible event states. Given the unique signal, a maze wheel is allowed to rotate fully in one direction. Given an incorrect signal, both the maze wheel and a pin wheel lock in position.

  2. 49 CFR 230.97 - Crank pins.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Crank pins. 230.97 Section 230.97 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION STEAM LOCOMOTIVE INSPECTION AND MAINTENANCE STANDARDS Steam Locomotives and Tenders Driving...

  3. Mesoscopic pinning forces in neutron star crusts

    NASA Astrophysics Data System (ADS)

    Seveso, S.; Pizzochero, P. M.; Grill, F.; Haskell, B.

    2016-02-01

    The crust of a neutron star is thought to be comprised of a lattice of nuclei immersed in a sea of free electrons and neutrons. As the neutrons are superfluid, their angular momentum is carried by an array of quantized vortices. These vortices can pin to the nuclear lattice and prevent the neutron superfluid from spinning down, allowing it to store angular momentum which can then be released catastrophically, giving rise to a pulsar glitch. A crucial ingredient for this model is the maximum pinning force that the lattice can exert on the vortices, as this allows us to estimate the angular momentum that can be exchanged during a glitch. In this paper, we perform, for the first time, a detailed and quantitative calculation of the pinning force per unit length acting on a vortex immersed in the crust and resulting from the mesoscopic vortex-lattice interaction. We consider realistic vortex tensions, allow for displacement of the nuclei and average over all possible orientations of the crystal with respect to the vortex. We find that, as expected, the mesoscopic pinning force becomes weaker for longer vortices and is generally much smaller than previous estimates, based on vortices aligned with the crystal. Nevertheless, the forces we obtain still have maximum values of the order of fpin ≈ 1015 dyn cm-1, which would still allow for enough angular momentum to be stored in the crust to explain large Vela glitches, if part of the star is decoupled during the event.

  4. Flux pinning and stabilizer studies. Final report

    SciTech Connect

    Collings, E.W.

    1994-11-29

    A synopsis of the results of the flux-pinning and stabilizer studies that form the central theme of the subject contract is followed by a list of papers that were published during the period August 28, 1986 to November 31, 1992.

  5. Vortex pinning properties in Fe-chalcogenides

    NASA Astrophysics Data System (ADS)

    Leo, A.; Grimaldi, G.; Guarino, A.; Avitabile, F.; Nigro, A.; Galluzzi, A.; Mancusi, D.; Polichetti, M.; Pace, S.; Buchkov, K.; Nazarova, E.; Kawale, S.; Bellingeri, E.; Ferdeghini, C.

    2015-12-01

    Among the families of iron-based superconductors, the 11-family is one of the most attractive for high field applications at low temperatures. Optimization of the fabrication processes for bulk, crystalline and/or thin film samples is the first step in producing wires and/or tapes for practical high power conductors. Here we present the results of a comparative study of pinning properties in iron-chalcogenides, investigating the flux pinning mechanisms in optimized Fe(Se{}1-xTe x ) and FeSe samples by current-voltage characterization, magneto-resistance and magnetization measurements. In particular, from Arrhenius plots in magnetic fields up to 9 T, the activation energy is derived as a function of the magnetic field, {U}0(H), whereas the activation energy as a function of temperature, U(T), is derived from relaxation magnetization curves. The high pinning energies, high upper critical field versus temperature slopes near critical temperatures, and highly isotropic pinning properties make iron-chalcogenide superconductors a technological material which could be a real competitor to cuprate high temperature superconductors for high field applications.

  6. 8. DETAIL VIEW OF PIN CONNECTION, NORTH WEB, SHOWING FLOOR ...

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

    8. DETAIL VIEW OF PIN CONNECTION, NORTH WEB, SHOWING FLOOR BEAM, STRINGERS, LATTICE BRACING, EYEBARS, AND PIN, LOOKING SOUTH - Four Mile Bridge, Spanning Elk River on County Road 42, Steamboat Springs, Routt County, CO

  7. Vortex creep and thermal depinning within strong pinning theory

    NASA Astrophysics Data System (ADS)

    Willa, Roland; Buchacek, Martin; Geshkenbein, Vadim B.; Blatter, Gianni

    Vortex pinning in type-II superconductors can occur through the collective action of many pins (weak collective pinning scenario) or through plastic deformations induced by a low density of defects (strong pinning scenario). For the latter case, a new formalism has recently be developed to provide a quantitative link between the microscopic pinning landscape and experimentally accessible quantities describing pinning on a macroscopic level. Examples are the critical current density jc, the I- V characteristics, or the ac Campbell length λC. Inspired by the original work of Larkin and Brazovskii on density wave pinning, we have extended the strong pinning formalism to account for thermal depinning of flux lines and vortex creep.

  8. Timing analysis of PWR fuel pin failures

    SciTech Connect

    Jones, K.R.; Wade, N.L.; Katsma, K.R.; Siefken, L.J. ); Straka, M. )

    1992-09-01

    This report discusses research conducted to develop and demonstrate a methodology for calculation of the time interval between receipt of the containment isolation signals and the first fuel pin failure for loss-of-coolant accidents (LOCAs). Demonstration calculations were performed for a Babcock and Wilcox (B W) design (Oconee) and a Westinghouse (W) four-loop design (Seabrook). Sensitivity studies were performed to assess the impacts of fuel pin burnup, axial peaking factor, break size, emergency core cooling system availability, and main coolant pump trip on these times. The analysis was performed using the following codes: FRAPCON-2, for the calculation of steady-state fuel behavior; SCDAP/RELAP5/MOD3 and TRACPF1/MOD1, for the calculation of the transient thermal-hydraulic conditions in the reactor system; and FRAP-T6, for the calculation of transient fuel behavior. In addition to the calculation of fuel pin failure timing, this analysis provides a comparison of the predicted results of SCDAP/RELAP5/MOD3 and TRAC-PF1/MOD1 for large-break LOCA analysis. Using SCDAP/RELAP5/MOD3 thermal-hydraulic data, the shortest time intervals calculated between initiation of containment isolation and fuel pin failure are 10.4 seconds and 19.1 seconds for the B W and W plants, respectively. Using data generated by TRAC-PF1/MOD1, the shortest intervals are 10.3 seconds and 29.1 seconds for the B W and W plants, respectively. These intervals are for a double-ended, offset-shear, cold leg break, using the technical specification maximum peaking factor and applied to fuel with maximum design burnup. Using peaking factors commensurate with actual burnups would result in longer intervals for both reactor designs. This document provides appendices K and L of this report which provide plots for the timing analysis of PWR fuel pin failures for Oconee and Seabrook respectively.

  9. Effects of Pin Detached Space on Heat Transfer and Pin-Fin Arrays

    SciTech Connect

    Siw, Sin C.; Chyu, Minking K.; Shih, Tom I-P.; Alvin, Mary Anne

    2012-08-01

    Heat transfer and pressure characteristics in a rectangular channel with pin-fin arrays of partial detachment from one of the endwalls have been experimentally studied. The overall channel geometry (W = 76.2 mm, E = 25.4 mm) simulates an internal cooling passage of wide aspect ratio (3:1) in a gas turbine airfoil. With a given pin diameter, D = 6.35 mm = ¼E, three different pin-fin height-to-diameter ratios, H/D = 4, 3, and 2, were examined. Each of these three cases corresponds to a specific pin array geometry of detachment spacing (C) between the pin tip and one of the endwalls, i.e., C/D = 0, 1, 2, respectively. The Reynolds number, based on the hydraulic diameter of the unobstructed cross-section and the mean bulk velocity, ranges from 10,000 to 25,000. The experiment employs a hybrid technique based on transient liquid crystal imaging to obtain the distributions of the local heat transfer coefficient over all of the participating surfaces, including the endwalls and all the pin elements. Experimental results reveal that the presence of a detached space between the pin tip and the endwall has a significant effect on the convective heat transfer and pressure loss in the channel. The presence of pin-to-endwall spacing promotes wall-flow interaction, generates additional separated shear layers, and augments turbulent transport. In general, an increase in detached spacing, or C/D, leads to lower heat transfer enhancement and pressure drop. However, C/D = 1, i.e., H/D = 3, of a staggered array configuration exhibits the highest heat transfer enhancement, followed by the cases of C/D = 0 and C/D = 2, i.e., H/D = 4 or 2, respectively.

  10. Pin Load Control Applied to Retractable Pin Tool Technology and its Characterization

    NASA Technical Reports Server (NTRS)

    Oelgoetz, Peter

    2000-01-01

    Until the development of retractable pin tool (RPT) technology, friction stir welding (FSW) was limited to constant thickness joining of aluminum materials and the choices of keyhole elimination focused on traditional fusion and plug weld repair techniques. An invention, US Patent Number 5,893.507, "Auto-Adjustable Pin Tool for Friction Stir Welding" assigned to NASA, demonstrated an approach to resolve these serious drawbacks. This approach brings forth a technique that allows the crater, or keyhole, to be closed out automatically at the end of the weld joint without adding any additional equipment or material. Also the probe length can be varied automatically in the weld joint to compensate for material thickness changes, such as, in a tapered joint. This paper reports the effects of pin extension and retraction rates in the weld joint and its correlation to weld quality. The investigation utilized a pin load-detecting device that was integrated in the Phase 2A RPT designed by Boeing for NASA/MSFC. The RPT modification provided pin load data that was accessed and used to eliminate root side indications and determine pin manipulation rates necessary to produce consistence homogeneous joints.

  11. Pin Load Control Applied to Retractable Pin Tool Technology and Its Characterization

    NASA Technical Reports Server (NTRS)

    Olegoetz, P.

    1999-01-01

    Until the development of retractable pin tool (RPT) technology, friction stir welding (FSW) was limited to constant thickness joining of aluminum materials and the choices of keyhole elimination focused on traditional fusion and plug weld repair techniques. An invention, US Patent Number 5,893,507, "Auto-Adjustable Pin Tool for Friction Stir Welding" assigned to NASA, demonstrated an approach to resolve these serious drawbacks. This approach brings forth a technique that allows the crater, or keyhole, to be closed out automatically at the end of the weld joint without adding any additional equipment or material. Also the probe length can be varied automatically in the weld joint to compensate for material thickness changes, such as, in a tapered joint. This paper reports the effects of pin extension and retraction rates in the weld joint and its correlation to weld quality. The investigation utilized a pin load-detecting device that was integrated in the Phase IIA RPT designed by Boeing for NASA/MSFC. The RPT modification provided pin load data that was accessed and used to eliminate root side indications and determine pin manipulation rates necessary to produce consistence homogeneous joints.

  12. Pin Load Control Applied to Retractable Pin Tool Technology and its Characterization

    NASA Technical Reports Server (NTRS)

    Oelgoetz, Peter A.

    2000-01-01

    Until the development of retractable pin tool (RPT) technology, friction stir welding (FSW) was limited to constant thickness joining of aluminum materials and the choices of keyhole elimination focused on traditional fusion and plug weld repair techniques. An invention, US Patent Number 5,893,507, "Auto-Adjustable Pin Tool for Friction Stir Welding" assigned to NASA, demonstrated an approach to resolve these serious drawbacks. This approach brings forth a technique that allows the crater, or keyhole, to be closed out automatically at the end of the weld joint without adding any additional equipment or material. Also the probe length can be varied automatically in the weld joint to compensate for material thickness changes, such as, in a tapered joint. This paper reports the effects of pin extension and retraction rates in the weld joint and its correlation to weld quality. The investigation utilized a pin load-detecting device that was integrated in the Phase 2A RPT designed by Boeing for NASA/MSFC. The RPT modification provided pin load data that was accessed and used to eliminate root side indications and determine pin manipulation rates necessary to produce consistence homogeneous joints.

  13. 18. SHEAR PIN, UNIT 24 GORGE POWERHOUSE. THE WICKET GATES ...

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

    18. SHEAR PIN, UNIT 24 GORGE POWERHOUSE. THE WICKET GATES ON THE TURBINE ARE EACH EQUIPPED WITH A SHEAR PIN AND OIL PRESSURE GAUGE. IF A GATE JAMS, THE PIN SMEARS AND THE CHANGE IN OIL PRESSURE TRIGGERS AN ALARM, 1989. - Skagit Power Development, Gorge Powerhouse, On Skagit River, 0.4 mile upstream from Newhalem, Newhalem, Whatcom County, WA

  14. A Biomechanical Comparison Of Pin Configurations Used For Percutaneous Pinning Of Distal Tibia Fractures In Children

    PubMed Central

    Brantley, Justin; Majumdar, Aditi; Jobe, J. Taylor; Kallur, Antony; Salas, Christina

    2016-01-01

    Background Percutaneous pin fixation is often used in conjunction with closed-reduction and cast immobilization to treat pediatric distal tibia fractures. The goal of this procedure is to maintain reduction and provide improved stabilization, in effort to facilitate a more anatomic union. We conducted a biomechanical study of the torsional and bending stability of three commonly used pin configurations in distal tibia fracture fixation. Methods A transverse fracture was simulated at the metaphyseal/diaphyseal junction in 15 synthetic tibias. Each fracture was reduced and fixed with two Kirschner wires, arranged in one of three pin configurations: parallel, retrograde, medial to lateral pins entering at the medial malleolus distal to the fracture (group A); parallel, antegrade, medial to lateral pins entering at the medial diaphysis proximal to the fracture (group B); or a cross-pin configuration with one retrograde, medial to lateral pin entering the medial malleolus distal to the fracture and the second an antegrade, medial to lateral pin entering at the medial diaphysis proximal to the fracture (group C). Stability of each construct was assessed by resistance to torsion and bending. Results Resistance to external rotation stress was significantly higher in group A than group B (P = 0.044). Resistance to internal rotation stress was significantly higher in group C than group B (P = 0.003). There was no significant difference in torsional stiffness when comparing group A with group C. Under a medial-directed load, group B and C specimens were significantly stiffer than those in group A (28 N/mm and 24 N/mm vs. 14 N/mm for A; P = 0.001 and P = 0.009, respectively) Conclusions None of the three pin configurations produced superior results with respect to all variables studied. Group A configuration provided the highest resistance to external rotation forces, which is the most clinically relevant variable under short-cast immobilization. Parallel, retrograde, medial

  15. Effects of three intramedullary pinning techniques on proximal pin location and articular damage in the canine tibia.

    PubMed

    Dixon, B C; Tomlinson, J L; Wagner-Mann, C C

    1994-01-01

    The effects of three different techniques of intramedullary (IM) pin placement on pin location and incidence of stifle joint injury were evaluated using 70 cadaver canine tibiae after mid-disphyseal osteotomy. In 50 tibiae, pins were placed retrograde in either a nondirected (group A) or a craniomedially directed fashion (group B) with 25 tibiae in each group. Pins were driven normograde (group N) in 20 tibiae. All the stifles were dissected to qualitatively evaluate pin interference with different joint structures. End-on radiographs of the tibial plateaus were used to quantitatively evaluate pin location. Interference with the caudal cruciate ligament, medial meniscus, lateral meniscus, or meniscal ligaments was not observed in any group. There was a significant association between pinning technique and incidence of involvement of the cranial cruciate ligament (P < .005), patella (P < .001), patellar ligament (P < .005), and femoral condyle (P < .01). Pin location for group A was significantly different from either other group in a cranial-caudal direction (P = .003), and was significantly different from group N in a medial-lateral direction (P = .005). No significant difference was observed between pin location for groups B and N in either plane. It was concluded that although nondirected retrograde pinning cannot be recommended, retrograde pins directed craniomedially may be an acceptable technique for the repair of proximal to mid-diaphyseal tibial fractures if care is taken to properly seat the pins. PMID:7871708

  16. Bending stiffness of conical and standard external fixator pins.

    PubMed

    Oni, O O; Capper, M; Soutis, C

    1993-10-01

    The bending stiffnesses of a conical and a standard external fixator pin have been compared. The pins were inserted into pilot holes in a piece of teak hardwood and loads of different magnitudes were applied at a fixed moment arm. Force-deflection curves were obtained for each pin, and stiffness (newtons per metre) and percentage stiffness reduction were calculated for each pilot hole size. The results show that deflection increased (i.e. stiffness decreased) with increasing force or diameter of pilot hole. This loss of stiffness was linear for the standard pin but was bimodal for the conical pin. PMID:8286671

  17. A comparative study of two types of sternal pins used for sternal closure: poly-L-lactide sternal pins versus uncalcined hydroxyapatite poly-L-lactide sternal pins.

    PubMed

    Fu, Xian-ming; Oshima, Hideki; Araki, Yoshimori; Narita, Yuji; Mutsuga, Masato; Okada, Noritaka; Tsunekawa, Tomohiro; Usui, Akihiko

    2013-12-01

    Bioabsorbable poly-L-lactide (PLLA) sternal pins are applied to reinforce sternal closure during cardiac surgery. However, these pins lack osteoconductivity. A new bioabsorbable sternal pin with osteoconductivity, made of uncalcined hydroxyapatite and poly-L-lactide (u-HA-PLLA) has been developed. This study was conducted to compare the two types of sternal pins in terms of sternal stability and healing after median sternotomy. Between October 2006 and January 2012, 105 patients underwent aortic surgery for aortic aneurysms or dissection via median sternotomy and sternal closure with sternal pins. Among these patients, 75 were followed for 12 months using serial computed tomography (CT). PLLA sternal pins were used in 30 patients (group A) and u-HA-PLLA sternal pins were used in 45 patients (group B). The incidence rates of transverse sternal dehiscence, anteroposterior displacement and complete sternal fusion were evaluated using CT. The cross-sectional cortical bone density area (CBDA) of the sternum around the sternal pins was examined to evaluate the osteoconductivity of the sternal pins. There were no significant differences between groups A and B in the sternal dehiscence rate (6.7 vs 4.4 %), sternal displacement rate (6.7 vs 2.2 %) or 12-month sternal fusion rate (63.3 vs 73.3 %). The CBDA around the sternal pins significantly increased between discharge and 12 months after surgery in group B (P < 0.001) but not in group A. These results show that u-HA-PLLA sternal pins exhibit certain osteoconductivity; however, both PLLA and u-HA-PLLA sternal pins provide comparable clinical outcomes regarding sternal stability and healing. PMID:23996506

  18. Quenched pinning and collective dislocation dynamics

    PubMed Central

    Ovaska, Markus; Laurson, Lasse; Alava, Mikko J.

    2015-01-01

    Several experiments show that crystalline solids deform in a bursty and intermittent fashion. Power-law distributed strain bursts in compression experiments of micron-sized samples, and acoustic emission energies from larger-scale specimens, are the key signatures of the underlying critical-like collective dislocation dynamics - a phenomenon that has also been seen in discrete dislocation dynamics (DDD) simulations. Here we show, by performing large-scale two-dimensional DDD simulations, that the character of the dislocation avalanche dynamics changes upon addition of sufficiently strong randomly distributed quenched pinning centres, present e.g. in many alloys as immobile solute atoms. For intermediate pinning strength, our results adhere to the scaling picture of depinning transitions, in contrast to pure systems where dislocation jamming dominates the avalanche dynamics. Still stronger disorder quenches the critical behaviour entirely. PMID:26024505

  19. Quenched pinning and collective dislocation dynamics.

    PubMed

    Ovaska, Markus; Laurson, Lasse; Alava, Mikko J

    2015-01-01

    Several experiments show that crystalline solids deform in a bursty and intermittent fashion. Power-law distributed strain bursts in compression experiments of micron-sized samples, and acoustic emission energies from larger-scale specimens, are the key signatures of the underlying critical-like collective dislocation dynamics - a phenomenon that has also been seen in discrete dislocation dynamics (DDD) simulations. Here we show, by performing large-scale two-dimensional DDD simulations, that the character of the dislocation avalanche dynamics changes upon addition of sufficiently strong randomly distributed quenched pinning centres, present e.g. in many alloys as immobile solute atoms. For intermediate pinning strength, our results adhere to the scaling picture of depinning transitions, in contrast to pure systems where dislocation jamming dominates the avalanche dynamics. Still stronger disorder quenches the critical behaviour entirely. PMID:26024505

  20. Scroll waves pinned to moving heterogeneities

    NASA Astrophysics Data System (ADS)

    Ke, Hua; Zhang, Zhihui; Steinbock, Oliver

    2015-03-01

    Three-dimensional excitable systems can self-organize vortex patterns that rotate around one-dimensional phase singularities called filaments. In experiments with the Belousov-Zhabotinsky reaction and numerical simulations, we pin these scroll waves to translating inert cylinders and demonstrate the controlled repositioning of their rotation centers. If the pinning site extends only along a portion of the filament, the phase singularity is stretched out along the trajectory of the heterogeneity, which effectively writes the singularity into the system. Its trailing end point follows the heterogeneity with a lower velocity. This velocity, its dependence on the placement of the anchor, and the shape of the filament are explained by a curvature flow model.

  1. Influential Factors of Z-pin Bridging Force

    NASA Astrophysics Data System (ADS)

    Li, Chenghu; Wu, Zhe; Meng, Zhijun; Li, Muchen

    2014-08-01

    The nine-pin bridging force experiments are conducted at room temperature (20 °C) and at 75 °C. A three-dimensional z-pin unit cell for finite element analysis is established to study the influential factors of the z-pin bridging force. The experimental results show that the z-pin bridging force at 75 °C is smaller than at 20 °C. The z-pin bridging force is highly dependent on the surface area of z-pin. Therefore, it is feasible that the bridging force can be enhanced by changing the surface area of z-pin. The study also shows that the lay-up sequences of laminates have an impact on the z-pin bridging force, and the maximum bridging force of z-pin rises with the increase elastic modules of the resin. The z-pin bridging force reduces with rise of temperature for two reasons: The elastic modulus and shear strength of the resin decrease with rise of temperature, forcing the bridging force to reduce and the resin makes some clamping effect on z-pin, pushing the bridging force to increase.

  2. Statistical-summation theory of weak flux-line pins

    SciTech Connect

    Kerchner, H.R.

    1981-01-01

    A random array of flux-line-pinning defects is shown to produce a large, bulk pinning-force density even if the pins individually fail to satisfy the threshold criterion. By using a simplified model defect-FLL interaction, approximate expressions are obtained for the critical pinning-force density F/sub c/. The theory predicts that in materials with a weak pinning structure F/sub c/ depends only weakly on magnetic field except within narrow peaks near the upper and lower critical fields. The width of the peaks increases as the pinning is made stronger. A broad, dome-shaped peak in F/sub c/ and scaling-law behavior, both of which are usually associated with large F/sub c/ materials, is the strong-pinning limit of this theory.

  3. Rotary pin-in-maze discriminator

    DOEpatents

    Benavides, G.L.

    1997-05-06

    A discriminator apparatus and method that discriminates between a unique signal and any other (incorrect) signal are disclosed. The unique signal is a sequence of events; each event can assume one of two possible event states. Given the unique signal, a maze wheel is allowed to rotate fully in one direction. Given an incorrect signal, both the maze wheel and a pin wheel lock in position. 4 figs.

  4. Channelized coplanar waveguide pin-diode switches

    NASA Technical Reports Server (NTRS)

    Ponchak, G. E.; Simons, R. N.

    1989-01-01

    Three different types of p-i-n diode, reflective CPW switches are presented. The first two switches are the series and the shunt mounted diode switches. Each has achieved greater than 15 dB of isolation over a broad bandwidth. The third switch is a narrow band, high isolation switched filter which has achieved 19 dB of isolation. Equivalent circuits and measured performance for each switch is presented.

  5. Timing analysis of PWR fuel pin failures

    SciTech Connect

    Jones, K.R.; Wade, N.L.; Katsma, K.R.; Siefken, L.J. ); Straka, M. )

    1992-09-01

    Research has been conducted to develop and demonstrate a methodology for calculation of the time interval between receipt of the containment isolation signals and the first fuel pin failure for loss-of-coolant accidents (LOCAs). Demonstration calculations were performed for a Babcock and Wilcox (B W) design (Oconee) and a Westinghouse (W) four-loop design (Seabrook). Sensitivity studies were performed to assess the impacts of fuel pin bumup, axial peaking factor, break size, emergency core cooling system availability, and main coolant pump trip on these times. The analysis was performed using the following codes: FRAPCON-2, for the calculation of steady-state fuel behavior; SCDAP/RELAP5/MOD3 and TRACPF1/MOD1, for the calculation of the transient thermal-hydraulic conditions in the reactor system; and FRAP-T6, for the calculation of transient fuel behavior. In addition to the calculation of fuel pin failure timing, this analysis provides a comparison of the predicted results of SCDAP/RELAP5/MOD3 and TRAC-PFL/MOD1 for large-break LOCA analysis. Using SCDAP/RELAP5/MOD3 thermal-hydraulic data, the shortest time intervals calculated between initiation of containment isolation and fuel pin failure are 10.4 seconds and 19.1 seconds for the B W and W plants, respectively. Using data generated by TRAC-PF1/MOD1, the shortest intervals are 10.3 seconds and 29.1 seconds for the B W and W plants, respectively. These intervals are for a double-ended, offset-shear, cold leg break, using the technical specification maximum peaking factor and applied to fuel with maximum design bumup. Using peaking factors commensurate widi actual bumups would result in longer intervals for both reactor designs. This document also contains appendices A through J of this report.

  6. Performance measurements of hybrid PIN diode arrays

    SciTech Connect

    Jernigan, J.G.; Arens, J.F. . Space Sciences Lab.); Kramer, G. ); Collins, T.; Herring, J. ); Shapiro, S.L. ); Wilburn, C.D. )

    1990-05-01

    We report on the successful effort to develop hybrid PIN diode arrays and to demonstrate their potential as components of vertex detectors. Hybrid pixel arrays have been fabricated by the Hughes Aircraft Co. by bump bonding readout chips developed by Hughes to an array of PIN diodes manufactured by Micron Semiconductor Inc. These hybrid pixel arrays were constructed in two configurations. One array format having 10 {times} 64 pixels, each 120 {mu}m square, and the other format having 256 {times} 256 pixels, each 30 {mu}m square. In both cases, the thickness of the PIN diode layer is 300 {mu}m. Measurements of detector performance show that excellent position resolution can be achieved by interpolation. By determining the centroid of the charge cloud which spreads charge into a number of neighboring pixels, a spatial resolution of a few microns has been attained. The noise has been measured to be about 300 electrons (rms) at room temperature, as expected from KTC and dark current considerations, yielding a signal-to-noise ratio of about 100 for minimum ionizing particles. 4 refs., 13 figs.

  7. Sorting signals for PIN1 trafficking and localization.

    PubMed

    Marcote, María Jesús; Sancho-Andrés, Gloria; Soriano-Ortega, Esther; Aniento, Fernando

    2016-08-01

    PIN-FORMED (PIN) family proteins direct polar auxin transport based on their asymmetric (polar) localization at the plasma membrane. In the case of PIN1, it mainly localizes to the basal (rootward) plasma membrane domain of stele cells in root meristems. Vesicular trafficking events, such as clathrin-dependent PIN1 endocytosis and polar recycling, are probably the main determinants for PIN1 polar localization. However, very little is known about the signals which may be involved in binding the μ-adaptin subunit of clathrin adaptor complexes (APs) for sorting of PIN1 within clathrin-coated vesicles, which can determine its trafficking and localization. We have performed a systematic mutagenesis analysis to investigate putative sorting motifs in the hydrophilic loop of PIN1. We have found that a non-canonical motif, based in a phenylalanine residue, through the binding of μA(μ2)- and μD(μ3)-adaptin, is important for PIN1 endocytosis and for PIN1 traffcking along the secretory pathway, respectively. In addition, tyrosine-based motifs, which also bind different μ-adaptins, could also contribute to PIN1 trafficking and localization. PMID:27603315

  8. The effect of indole-3-carbinol on PIN1 and PIN2 in Arabidopsis roots.

    PubMed

    Katz, Ella; Nisani, Sophia; Sela, Mor; Behar, Hila; Chamovitz, Daniel A

    2015-01-01

    The phytochemical indole-3-carbinol is produced in Cruciferous plants upon tissue rapture and deters herbivores. We recently showed that indole-3-carbinol modulates auxin signaling in root tips. Here we present transcript profiling experiments which further reveal the influence of indole-3-carbinol on auxin signaling in root tips, and also show that I3C affects auxin transporters. Brief treatment with indole-3-carbinol led to a reduction in the amount of PIN1 and to mislocalization of PIN2. PMID:26252364

  9. The effect of indole-3-carbinol on PIN1 and PIN2 in Arabidopsis roots

    PubMed Central

    Katz, Ella; Nisani, Sophia; Sela, Mor; Behar, Hila; Chamovitz, Daniel A

    2015-01-01

    The phytochemical indole-3-carbinol is produced in Cruciferous plants upon tissue rapture and deters herbivores. We recently showed that indole-3-carbinol modulates auxin signaling in root tips. Here we present transcript profiling experiments which further reveal the influence of indole-3-carbinol on auxin signaling in root tips, and also show that I3C affects auxin transporters. Brief treatment with indole-3-carbinol led to a reduction in the amount of PIN1 and to mislocalization of PIN2. PMID:26252364

  10. A mechanism to pin skyrmions in chiral magnets.

    PubMed

    Liu, Ye-Hua; Li, You-Quan

    2013-02-20

    We propose a mechanism to pin skyrmions in chiral magnetic thin films by introducing local maxima of magnetic exchange strength as pinning centers. The local maxima can be realized by engineering the local density of itinerant electrons. The stationary properties and the dynamical pinning and depinning processes of an isolated skyrmion around a pinning center are studied. We carry out numerical simulations of the Landau-Lifshitz-Gilbert (LLG) equation and find a way to control the position of an isolated skyrmion in a pinning center lattice using electric current pulses. The results are verified by a Thiele equation analysis. We also find that the critical current to depin a skyrmion, which is estimated to have order of magnitude 10(7)-10(8) A m(-2), has linear dependence on the pinning strength. PMID:23339842

  11. A mechanism to pin skyrmions in chiral magnets

    NASA Astrophysics Data System (ADS)

    Liu, Ye-Hua; Li, You-Quan

    2013-02-01

    We propose a mechanism to pin skyrmions in chiral magnetic thin films by introducing local maxima of magnetic exchange strength as pinning centers. The local maxima can be realized by engineering the local density of itinerant electrons. The stationary properties and the dynamical pinning and depinning processes of an isolated skyrmion around a pinning center are studied. We carry out numerical simulations of the Landau-Lifshitz-Gilbert (LLG) equation and find a way to control the position of an isolated skyrmion in a pinning center lattice using electric current pulses. The results are verified by a Thiele equation analysis. We also find that the critical current to depin a skyrmion, which is estimated to have order of magnitude 107-108 A m-2, has linear dependence on the pinning strength.

  12. Contact stresses in pin-loaded orthotropic plates

    NASA Technical Reports Server (NTRS)

    Hyer, M. W.; Klang, E. C.

    1984-01-01

    The effects of pin elasticity, friction, and clearance on the stresses near the hole in a pin-loaded orthotropic plate are described. The problem is modeled as a contact elasticity problem using complex variable theory, the pin and the plate being two elastic bodies interacting through contact. This modeling is in contrast to previous works which assumed that the pin is rigid or that it exerts a known cosinusoidal radial traction on the hole boundary. Neither of these approaches explicitly involves a pin. A collocation procedure and iteration were used to obtain numerical results for a variety of plate and pin elastic properties and various levels of friction and clearance. Collocation was used to enforce the boundary and iteration was used to find the contact and no-slip regions on the boundary. Details of the numerical scheme are discussed.

  13. Nanobubble stability induced by contact line pinning

    NASA Astrophysics Data System (ADS)

    Liu, Yawei; Zhang, Xianren

    2013-01-01

    The origin of surface nanobubbles stability is a controversial topic since nanobubbles were first observed. Here, we propose a mechanism that the three-phase contact line pinning, which results from the intrinsic nanoscale physical roughness or chemical heterogeneities of substrates, leads to stable surface nanobubbles. Using the constrained lattice density functional theory (LDFT) and kinetic LDFT, we prove thermodynamically and dynamically that the state with nanobubbles is in fact a thermodynamical metastable state. The mechanism consistent with the classical nucleation theory can interpret most of experimental characteristics for nanobubbles qualitatively, and predict relationships among the gas-side nanobubble contact angle, nanobubble size, and chemical potential.

  14. Current-voltage characteristics in collective pinning

    SciTech Connect

    de la Cruz, F.; Luzuriaga, J.; Martinez, E.N.; Osquiguil, E.J.

    1987-11-01

    The critical-current curves of amorphous samples which exhibit collective flux pinning have been analyzed, and it was found that the nonlinear part can be fitted by an expression of the form V(I)approx.((I-I/sub K/)/I/sub K/)/sup zeta/. This form, which could be due to critical behavior, is consistent with an interpretation of the unpinning of vortices in the collective regime as a phase transition between the static flux-line lattice (FLL) and the FLL in steady-state movement as has been proposed by Fisher.

  15. Semiconducting glasses with flux pinning inclusions

    DOEpatents

    Johnson, William L.; Poon, Siu-Joe; Duwez, Pol E.

    1981-01-01

    A series of amorphous superconducting glassy alloys containing 1% to 10% by volume of flux pinning crystalline inclusions have been found to have potentially useful properties as high field superconducting magnet materials. The alloys are prepared by splat cooling by the piston and anvil technique. The alloys have the composition (TM).sub.90-70 (M).sub.10-30 where TM is a transition metal selected from at least one metal of Groups IVB, VB, VIB, VIIB or VIIIB of the Periodic Table such as Nb, Mo, Ru, Zr, Ta, W or Re and M is at least one metalloid such as B, P, C, N, Si, Ge or Al.

  16. Inventory of miscellaneous streams

    SciTech Connect

    Haggard, R.D.

    1998-08-14

    Miscellaneous streams discharging to the soil column on the Hanford Site are subject to requirements of several milestones identified in Consent Order No. DE 9INM-177 (Ecology and DOE 1991). The Plan and Schedule for Disposition and Regulatory Compliance for Miscellaneous Stream (DOE/RL-93-94) provides a plan and schedule for the disposition of miscellaneous streams to satisfy one of the Section 6.0 requirements of the Consent Order. One of the commitments (Activity 6-2.2) established in the plan and schedule is to annually update, the miscellaneous streams inventory. This document constitutes the 1998 revision of the miscellaneous streams inventory. Miscellaneous stream discharges were grouped into four permitting categories (Table 1). The first miscellaneous streams Permit (ST 4508) was issued May 30, 1997, to cover wastewater discharges from hydrotesting, maintenance, and construction activities. The second miscellaneous streams Permit (ST4509) covers discharges from cooling water and condensate discharges. The third permit application for category three waste streams was eliminated by recategorizing waste streams into an existing miscellaneous streams permit or eliminating stream discharges. Elimination of the third categorical permit application was approved by Ecology in January 1997 (Ecology 1997). The fourth permit application, to cover storm water, is due to Ecology in September 1998. Table 1 provides a history of the miscellaneous streams permitting activities.

  17. Retractable pin dual in-line package test clip

    DOEpatents

    Bandzuch, Gregory S.; Kosslow, William J.

    1996-01-01

    This invention is a Dual In-Line Package (DIP) test clip for use when troubleshooting circuits containing DIP integrated circuits. This test clip is a significant improvement over existing DIP test clips in that it has retractable pins which will permit troubleshooting without risk of accidentally shorting adjacent pins together when moving probes to different pins on energized circuits or when the probe is accidentally bumped while taking measurements.

  18. Retractable pin dual in-line package test clip

    SciTech Connect

    Bandzuch, G.S.; Kosslow, W.J

    1993-12-31

    This invention is a Dual In-line Package (DIP) test clip for use when troubleshooting circuits containing DIP integrated circuits. This test clip is a significant improvement over existing DIP test clips in that it has retractable pins which will permit troubleshooting without risk of accidentally shorting adjacent pins together when moving probes to different pins on energized circuits or when the probe is accidentally bumped while taking measurements.

  19. Pinning synchronization of discrete dynamical networks with delay coupling

    NASA Astrophysics Data System (ADS)

    Cheng, Ranran; Peng, Mingshu; Zuo, Jun

    2016-05-01

    The purpose of this paper is to investigate the pinning synchronization analysis for nonlinear coupled delayed discrete dynamical networks with the identical or nonidentical topological structure. Based on the Lyapunov stability theory, pinning control method and linear matrix inequalities, several adaptive synchronization criteria via two kinds of pinning control method are obtained. Two examples based on Rulkov chaotic system are included to illustrate the effectiveness and verification of theoretical analysis.

  20. Percutaneous Pinning of Fifth Carpal–Metacarpal Fracture–Dislocations: An Alternative Pin Trajectory

    PubMed Central

    Lee, Sue Y.; Raphael, James S.

    2008-01-01

    Traditional management of unstable fourth and fifth carpal–metacarpal (CMC) fracture–dislocations (fx–dislocs) of the hand includes closed reduction and percutaneous pinning (CRPP) versus open reduction internal fixation (ORIF). Traditional trajectory of pin placement is toward the base of the hook of the hamate. Our case series of CMC fx–dislocs treated with this trajectory led to the development of ulnar deep motor branch symptoms (sxs). We attempt to propose an alternative trajectory that could lower the chance of iatrogenic injury. Five fresh frozen cadaveric specimens underwent percutaneous pinning of the fifth CMC joint using fluoroscopic guidance. Each cadaver was dissected, and the proximity of the deep motor branch of the ulnar nerve was measured in relation to a pin that penetrated the volar cortex. Our results confirm the close proximity of the deep motor branch of the ulnar nerve to the volar cortex of the hamate and demonstrate the potential for iatrogenic injury during CRPP of the fifth CMC fx–dislocs, especially with penetration of the volar cortex. By demonstrating the close proximity of the deep motor branch to the volar cortex of the hamate in cadavers, we highlight the potential for iatrogenic injury with CRPP of CMC fx–dislocs as seen in our case series. We recommend a more midaxial starting point on the proximal metacarpal with a trajectory aimed at the midbody of the hamate to prevent penetration of the hamate volar cortex and limit the chances of iatrogenic injury. PMID:18780105

  1. Percutaneous pinning of fifth carpal-metacarpal fracture-dislocations: an alternative pin trajectory.

    PubMed

    Saing, Minn H; Lee, Sue Y; Raphael, James S

    2008-09-01

    Traditional management of unstable fourth and fifth carpal-metacarpal (CMC) fracture-dislocations (fx-dislocs) of the hand includes closed reduction and percutaneous pinning (CRPP) versus open reduction internal fixation (ORIF). Traditional trajectory of pin placement is toward the base of the hook of the hamate. Our case series of CMC fx-dislocs treated with this trajectory led to the development of ulnar deep motor branch symptoms (sxs). We attempt to propose an alternative trajectory that could lower the chance of iatrogenic injury. Five fresh frozen cadaveric specimens underwent percutaneous pinning of the fifth CMC joint using fluoroscopic guidance. Each cadaver was dissected, and the proximity of the deep motor branch of the ulnar nerve was measured in relation to a pin that penetrated the volar cortex. Our results confirm the close proximity of the deep motor branch of the ulnar nerve to the volar cortex of the hamate and demonstrate the potential for iatrogenic injury during CRPP of the fifth CMC fx-dislocs, especially with penetration of the volar cortex. By demonstrating the close proximity of the deep motor branch to the volar cortex of the hamate in cadavers, we highlight the potential for iatrogenic injury with CRPP of CMC fx-dislocs as seen in our case series. We recommend a more midaxial starting point on the proximal metacarpal with a trajectory aimed at the midbody of the hamate to prevent penetration of the hamate volar cortex and limit the chances of iatrogenic injury. PMID:18780105

  2. Development of 3D pseudo pin-by-pin calculation methodology in ANC

    SciTech Connect

    Zhang, B.; Mayhue, L.; Huria, H.; Ivanov, B.

    2012-07-01

    Advanced cores and fuel assembly designs have been developed to improve operational flexibility, economic performance and further enhance safety features of nuclear power plants. The simulation of these new designs, along with strong heterogeneous fuel loading, have brought new challenges to the reactor physics methodologies currently employed in the industrial codes for core analyses. Control rod insertion during normal operation is one operational feature in the AP1000{sup R} plant of Westinghouse next generation Pressurized Water Reactor (PWR) design. This design improves its operational flexibility and efficiency but significantly challenges the conventional reactor physics methods, especially in pin power calculations. The mixture loading of fuel assemblies with significant neutron spectrums causes a strong interaction between different fuel assembly types that is not fully captured with the current core design codes. To overcome the weaknesses of the conventional methods, Westinghouse has developed a state-of-the-art 3D Pin-by-Pin Calculation Methodology (P3C) and successfully implemented in the Westinghouse core design code ANC. The new methodology has been qualified and licensed for pin power prediction. The 3D P3C methodology along with its application and validation will be discussed in the paper. (authors)

  3. The Scaling Rule and Fluxon Core Pinning in a High-Field Superconductor with Artificially Introduced Pins

    NASA Astrophysics Data System (ADS)

    Cooley, Lance David

    Flux pinning affects virtually every aspect of high-field superconductivity. Its fundamental mechanism(s) are in principle derived from a complicated theory, but are in practice generally accessed through measuring the field dependence of the bulk flux pinning force (F _{p}(B)). The central piece of information is the shape of the F_{p }(B) curve: It is generally accepted that if, and only if, the curve's shape is constant while the temperature or pin dimension changes, one pinning mechanism is dominant (the 'scaling rule'). During the course of this thesis, we established that the shape of F_{p}(B) is affected by the statistical distribution of the elementary pinning forces (f_{p}). Contrary to prior beliefs, it was concluded that the shape of the bulk pinning force curve for fluxon core pinning is constant, when the distribution is broad, only if the microstructure is fractal. The peak of the F_ {p}(B) curve occurs at a lower field prior models predict, regardless of whether the shape of the curve is constant. When the distribution is narrow, a constant shape occurs, and has the shape predicted for core pinning and direct summation. Thus, the bulk pinning force curve and the elementary pinning mechanism are directly related by the scaling rule only when the f_ {p} distribution is narrow. Within this context, core pinning has been investigated with a specially fabricated Nb-Ti composite having artificially introduced pins, for which the f_{p } distribution is as narrow as can be made. By design, core pinning should be dominant; the shape of the F_{p}(B) curve does not, however, have the predicted form. The results can be explained by a new pinning mechanism, which incorporates the proximity effect and an anisotropic fluxon core, as proposed by Gurevich. It is concluded that the shape of the bulk pinning force curve is very sensitive to the proximity effect, and it can have a peak at a higher field than was previously thought possible for core pinning. The scaling

  4. Regex-Stream

    Energy Science and Technology Software Center (ESTSC)

    2012-09-01

    Log files are typically semi-or un-structured. To be useable, they need to be parsed into a standard, structured format. Regex-Stream facilitates parsing text files into structured data (JSON) in streams of data.

  5. Prioritized Contact Transport Stream

    NASA Technical Reports Server (NTRS)

    Hunt, Walter Lee, Jr. (Inventor)

    2015-01-01

    A detection process, contact recognition process, classification process, and identification process are applied to raw sensor data to produce an identified contact record set containing one or more identified contact records. A prioritization process is applied to the identified contact record set to assign a contact priority to each contact record in the identified contact record set. Data are removed from the contact records in the identified contact record set based on the contact priorities assigned to those contact records. A first contact stream is produced from the resulting contact records. The first contact stream is streamed in a contact transport stream. The contact transport stream may include and stream additional contact streams. The contact transport stream may be varied dynamically over time based on parameters such as available bandwidth, contact priority, presence/absence of contacts, system state, and configuration parameters.

  6. Epigallocatechin-gallate Suppresses Tumorigenesis by Directly Targeting Pin1

    SciTech Connect

    Urusova, Darya V.; Shim, Jung-Hyun; Kim, Dong Joon; Jung, Sung Keun; Zykova, Tatyana A.; Carper, Andria; Bode, Ann M.; Dong, Zigang

    2011-09-01

    The most active anticancer component in green tea is epigallocatechin-3-gallate (EGCG). The human peptidyl prolyl cis/trans isomerase (Pin1) plays a critical role in oncogenic signaling. Herein, we report the X-ray crystal structure of the Pin1/EGCG complex resolved at 1.9 Å resolution. Notably, the structure revealed the presence of EGCG in both the WW and PPIase domains of Pin1. The direct binding of EGCG with Pin1 was confirmed and the interaction inhibited Pin1 PPIase activity. In addition, proliferation of cells expressing Pin1 was inhibited and tumor growth in a xenograft mouse model was suppressed. The binding of EGCG with Arg17 in the WW domain prevented the binding of c-Jun, a well-known Pin1 substrate. EGCG treatment corresponded with a decreased abundance of cyclin D1 and diminution of 12-O-tetradecanoylphorbol-l3-acetate–induced AP-1 or NF-κB promoter activity in cells expressing Pin1. Overall, these results showed that EGCG directly suppresses the tumor-promoting effect of Pin1.

  7. Contact line pinning and the relationship between nanobubbles and substrates.

    PubMed

    Liu, Yawei; Wang, Jianjun; Zhang, Xianren; Wang, Wenchuan

    2014-02-01

    We report a theoretical study of nanobubble stabilization on a substrate by contact line pinning. In particular, we predict the magnitude of the pinning force required to stabilize a nanobubble and the threshold values of the pinning force that the substrate can provide. We show that the substrate chemistry and the local structures of substrate heterogeneity together determine whether or not surface nanobubbles are stable. We find that for stable nanobubbles, the contact angles are independent of substrate chemistry as its effects are cancelled out by the pinning effect. This prediction is in agreement with available experimental data. PMID:24511966

  8. Positioning and locking device for fuel pin to grid attachment

    DOEpatents

    Frick, Thomas M.; Wineman, Arthur L.

    1976-01-01

    A positioning and locking device for fuel pin to grid attachment provides an inexpensive means of positively positioning and locking the individual fuel pins which make up the driver fuel assemblies used in nuclear reactors. The device can be adapted for use with a currently used attachment grid assembly design and insures that the pins remain in their proper position throughout the in-reactor life of the assembly. This device also simplifies fuel bundle assembly in that a complete row of fuel pins can be added to the bundle during each step of assembly.

  9. Contact line pinning and the relationship between nanobubbles and substrates

    NASA Astrophysics Data System (ADS)

    Liu, Yawei; Wang, Jianjun; Zhang, Xianren; Wang, Wenchuan

    2014-02-01

    We report a theoretical study of nanobubble stabilization on a substrate by contact line pinning. In particular, we predict the magnitude of the pinning force required to stabilize a nanobubble and the threshold values of the pinning force that the substrate can provide. We show that the substrate chemistry and the local structures of substrate heterogeneity together determine whether or not surface nanobubbles are stable. We find that for stable nanobubbles, the contact angles are independent of substrate chemistry as its effects are cancelled out by the pinning effect. This prediction is in agreement with available experimental data.

  10. Heat transfer in a fuel pin shipping container. [IDENT 1578

    SciTech Connect

    Ingham, J.G.

    1980-11-11

    Maximum cladding temperatures occur when the IDENT 1578 fuel pin shipping container is installed in the T-3 Cask. The maximum allowable cladding temperature of 800/sup 0/F is reached when the rate of energy deposited in the 19-pin basket reaches 400 watts. Since 45% of the energy which is generated in the fuel escapes the 19-pin basket without being deposited, mostly gamma energy, the maximum allowable rate of heat generation is 400/.55 = 727 watts. Similarly, the maximum allowable cladding temperature of 800/sup 0/F is reached when the rate of energy deposited in the 40-pin basket reaches 465 watts. Since 33% of the energy which is generated in the fuel escapes the 40-pin basket without being deposited, mostly gamma energy, the maximum allowable rate of heat generation is 465/.66 = 704 watts. The IDENT 1578 fuel pin shipping container therefore meets its thermal design criteria. IDENT 1578 can handle fuel pins with a decay heat load of 600 watts while maintaining the maximum fuel pin cladding temperature below 800/sup 0/F. The emissivities which were determined from the test results for the basket tubes and container are relatively low and correspond to new, shiny conditions. As the IDENT 1578 container is exposed to high temperatures for extended periods of time during the transportation of fuel pins, the emissivities will probably increase. This will result in reduced temperatures.

  11. Thermal analysis of the FSP-1 fuel pin irradiation test

    SciTech Connect

    Lyon, W.F. III.

    1990-07-25

    Thermal analysis of a pin from the FSP-1 fuels irradiation test has been completed. The purpose of the analysis was to provide predictions of fuel pin temperatures, determine the flow regime within the lithium annulus of the test assembly, and provide a standardized model for a consistent basis of comparison between pins within the test assembly. The calculations have predicted that the pin is operating at slightly above the test design temperatures and that the flow regime within the lithium annulus is a laminar buoyancy driven flow. 7 refs., 5 figs.

  12. Effects of pin shape and array orientation on heat transfer and pressure loss in pin fin arrays

    NASA Astrophysics Data System (ADS)

    Metzger, D. E.; Fan, C. S.; Haley, S. W.

    1984-01-01

    In order to reduce the cooling airflow required by gas turbine blades, two families of pin fin array geometries which may potentially improve such air-cooled turbine blade airfoils' internal cooling performance are experimentally studied. One family uses circular cross section pins with various array orientations relative to the mean flow direction. The other family employs pins with an oblong cross section, again with various orientations. Heat transfer and pressure loss results indicate that the use of circular pins whose array orientation varies between the staggered and the inline can, in some cases, increase heat transfer while decreasing pressure loss. Elongated pins increased heat transfer, but with increased pressure loss. Pin surface heat transfer coefficients are double the endwall values.

  13. Lightning Pin Injection Testing on MOSFETS

    NASA Technical Reports Server (NTRS)

    Ely, Jay J.; Nguyen, Truong X.; Szatkowski, George N.; Koppen, Sandra V.; Mielnik, John J.; Vaughan, Roger K.; Wysocki, Philip F.; Celaya, Jose R.; Saha, Sankalita

    2009-01-01

    Lightning transients were pin-injected into metal-oxide-semiconductor field-effect transistors (MOSFETs) to induce fault modes. This report documents the test process and results, and provides a basis for subsequent lightning tests. MOSFETs may be present in DC-DC power supplies and electromechanical actuator circuits that may be used on board aircraft. Results show that unprotected MOSFET Gates are susceptible to failure, even when installed in systems in well-shielded and partial-shielded locations. MOSFET Drains and Sources are significantly less susceptible. Device impedance decreased (current increased) after every failure. Such a failure mode may lead to cascading failures, as the damaged MOSFET may allow excessive current to flow through other circuitry. Preliminary assessments on a MOSFET subjected to 20-stroke pin-injection testing demonstrate that Breakdown Voltage, Leakage Current and Threshold Voltage characteristics show damage, while the device continues to meet manufacturer performance specifications. The purpose of this research is to develop validated tools, technologies, and techniques for automated detection, diagnosis and prognosis that enable mitigation of adverse events during flight, such as from lightning transients; and to understand the interplay between lightning-induced surges and aging (i.e. humidity, vibration thermal stress, etc.) on component degradation.

  14. Optimizing Dynamical Network Structure for Pinning Control

    PubMed Central

    Orouskhani, Yasin; Jalili, Mahdi; Yu, Xinghuo

    2016-01-01

    Controlling dynamics of a network from any initial state to a final desired state has many applications in different disciplines from engineering to biology and social sciences. In this work, we optimize the network structure for pinning control. The problem is formulated as four optimization tasks: i) optimizing the locations of driver nodes, ii) optimizing the feedback gains, iii) optimizing simultaneously the locations of driver nodes and feedback gains, and iv) optimizing the connection weights. A newly developed population-based optimization technique (cat swarm optimization) is used as the optimization method. In order to verify the methods, we use both real-world networks, and model scale-free and small-world networks. Extensive simulation results show that the optimal placement of driver nodes significantly outperforms heuristic methods including placing drivers based on various centrality measures (degree, betweenness, closeness and clustering coefficient). The pinning controllability is further improved by optimizing the feedback gains. We also show that one can significantly improve the controllability by optimizing the connection weights. PMID:27067020

  15. Optimizing Dynamical Network Structure for Pinning Control.

    PubMed

    Orouskhani, Yasin; Jalili, Mahdi; Yu, Xinghuo

    2016-01-01

    Controlling dynamics of a network from any initial state to a final desired state has many applications in different disciplines from engineering to biology and social sciences. In this work, we optimize the network structure for pinning control. The problem is formulated as four optimization tasks: i) optimizing the locations of driver nodes, ii) optimizing the feedback gains, iii) optimizing simultaneously the locations of driver nodes and feedback gains, and iv) optimizing the connection weights. A newly developed population-based optimization technique (cat swarm optimization) is used as the optimization method. In order to verify the methods, we use both real-world networks, and model scale-free and small-world networks. Extensive simulation results show that the optimal placement of driver nodes significantly outperforms heuristic methods including placing drivers based on various centrality measures (degree, betweenness, closeness and clustering coefficient). The pinning controllability is further improved by optimizing the feedback gains. We also show that one can significantly improve the controllability by optimizing the connection weights. PMID:27067020

  16. Optimizing Dynamical Network Structure for Pinning Control

    NASA Astrophysics Data System (ADS)

    Orouskhani, Yasin; Jalili, Mahdi; Yu, Xinghuo

    2016-04-01

    Controlling dynamics of a network from any initial state to a final desired state has many applications in different disciplines from engineering to biology and social sciences. In this work, we optimize the network structure for pinning control. The problem is formulated as four optimization tasks: i) optimizing the locations of driver nodes, ii) optimizing the feedback gains, iii) optimizing simultaneously the locations of driver nodes and feedback gains, and iv) optimizing the connection weights. A newly developed population-based optimization technique (cat swarm optimization) is used as the optimization method. In order to verify the methods, we use both real-world networks, and model scale-free and small-world networks. Extensive simulation results show that the optimal placement of driver nodes significantly outperforms heuristic methods including placing drivers based on various centrality measures (degree, betweenness, closeness and clustering coefficient). The pinning controllability is further improved by optimizing the feedback gains. We also show that one can significantly improve the controllability by optimizing the connection weights.

  17. Heat transfer coefficients for staggered arrays of short pin fins

    NASA Technical Reports Server (NTRS)

    Vanfossen, G. J.

    1981-01-01

    Short pin fins are often used to increase that heat transfer to the coolant in the trailing edge of a turbine blade. Due primarily to limits of casting technology, it is not possible to manufacture pins of optimum length for heat transfer purposes in the trailing edge region. In many cases the pins are so short that they actually decrease the total heat transfer surface area compared to a plain wall. A heat transfer data base for these short pins is not available in the literature. Heat transfer coefficients on pin and endwall surfaces were measured for several staggered arrays of short pin fins. The measured Nusselt numbers when plotted versus Reynolds numbers were found to fall on a single curve for all surfaces tested. The heat transfer coefficients for the short pin fins (length to diameter ratios of 1/2 and 2) were found to be about a factor of two lower than data from the literature for longer pin arrays (length to diameter ratios of about 8).

  18. Heat transfer coefficients for staggered arrays of short pin fins

    NASA Technical Reports Server (NTRS)

    Vanfossen, G. J.

    1981-01-01

    Short pin fins are often used to increase the heat transfer to the coolant in the trailing edge of a turbine blade. Due primarily to limits of casting technology, it is not possible to manufacture pins of optimum length for heat transfer purposes in the trailing edge region. In many cases the pins are so short that they actually decrease the total heat transfer surface area compared to a plain wall. A heat transfer data base for these short pins is not available in the literature. Heat transfer coefficients on pin and endwall surfaces were measured for several staggered arrays of short pin fins. The measured Nusselt numbers when plotted versus Reynolds numbers were found to fall on a single curve for all surfaces tested. The heat transfer coefficients for the short pin fins (length to diameter ratios of 1/2 and 2) were found to be about a factor of two lower than data from the literature for longer pin arrays (length to diameter ratios of about 8).

  19. Percutaneous pinning of fractures of the distal radius.

    PubMed

    Alm-Paulsen, Paal Sandoe; Rod, Oyvind; Rød, Kristian; Rajabi, Benjamin; Russwurm, Harald; Finsen, Vilhjalmur

    2012-09-01

    Reduction of fractures of the distal radius is often supplemented with percutaneous pinning, but there is little evidence that this affects the clinical outcome. A total of 43 patients with pinned, and 296 with conservatively-treated, fractures were reviewed a mean of 6 (range 3-13) years after injury. We found controls among the conservatively-treated patients who matched 30 of the patients with pinned fractures with respect to age, sex, trauma energy, and radiographic measurements at injury. Clinical and radiological results of the two groups were compared and contrasted. There was a trend for better radiological results in patients with pinned fractures, but not significantly so, and no difference in clinical variables. We identified seven published randomised studies in which pinning was compared with reduction and plaster of Paris alone. Most reported better radiological results at review. The three smallest studies with the shortest follow-up reported better clinical outcome for pinned fractures, while the remaining four studies found no significant clinical benefit from pinning. Although the radiological results were improved by percutaneous pinning in addition to reduction and plaster of Paris, the clinical outcome in extra-articular and simple intra-articular fractures seemed unaffected. PMID:22694081

  20. FSW of Tapered Thickness Welds using an Adjustable Pin Tool

    NASA Technical Reports Server (NTRS)

    Adams, Glynn; Venable, Richard; Lawless, Kirby; Smelser, Jerry (Technical Monitor)

    2002-01-01

    This viewgraph presentation describes the advantages of tapered thickness welds in FSW (friction stir welding), the structure of FSW welds, the adjustable pin tool used in FSW. Other topics described include compliance and temperature measurement in a FSW system, loads and torque upon the pin tool and its ability to penetrate different metals, and the results and metallurgy of FSW welds.

  1. Alignment tool facilitates pin placement on irregular horizontal surfaces

    NASA Technical Reports Server (NTRS)

    Boyle, J. V.

    1966-01-01

    Alignment tool facilitates spotting and cementing plastic pins on the true vertical to irregular concave and convex surfaces. The tool consists of a wood tripod with individually adjustable legs, a wood block with a hole for placing the pins and two spirit levels at a 90 degree angle for easy alignment.

  2. 41. VIEW OF WEST BASCULE LEAF LOCKING PINS IN EXTENDED ...

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

    41. VIEW OF WEST BASCULE LEAF LOCKING PINS IN EXTENDED POSITION - PINS FIT INTO MATCHING BUSHINGS ON THE EAST LEAF AND SECURE THE EAST AND WEST SECTIONS WHEN THE BRIDGE IS DOWN. - Tomlinson Bridge, Spanning Quinnipiac River at Forbes Street (U.S. Route 1), New Haven, New Haven County, CT

  3. Optical fuel pin scanner. [Patent application; for reading identifications

    DOEpatents

    Kirchner, T.L.; Powers, H.G.

    1980-12-09

    This patent relates to an optical identification system developed for post-irradiation disassembly and analysis of fuel bundle assemblies. The apparatus is designed to be lowered onto a stationary fuel pin to read identification numbers or letters imprinted on the circumference of the top fuel pin and cap. (DLC)

  4. The pin-amalgam restoration. Part 1. A review.

    PubMed

    Evans, J R; Wetz, J H

    1977-01-01

    A review of the literature indicates that the use of pins to support amalgam or cast gold restorations in advanced caries in posterior teeth is a quick and relatively inexpensive method of restoring teeth otherwise doomed to extraction. However, the use of pins demands a careful and skillful dentist who understands the morphology of these teeth and the proper use of the materials if injury to the pulp, accidental perforations, crazing of the dentin, and splitting of teeth are to be prevented. Until more objective and controlled studies are completed, the use of cemented pins vs. self-threading pins remains a matter of empirical and personal preference. It is clear that success in the use of any pin or pins depends more on the dentist's skill and judgment than on the particular type of pin technique used. In order to more objectively evaluate the use of pin-amalgam restorations, Part 11 of this study will analyze the results obtained in the Clinic at Tufts University School of Dental Medicine. PMID:318695

  5. Destabilizing interactions among [PSI(+)] and [PIN(+)] yeast prion variants.

    PubMed Central

    Bradley, Michael E; Liebman, Susan W

    2003-01-01

    The yeast Sup35 and Rnq1 proteins can exist in either the noninfectious soluble forms, [psi-] or [pin-], respectively, or the multiple infectious amyloid-like forms called [PSI+] or [PIN+] prion variants (or prion strains). It was previously shown that [PSI+] and [PIN+] prions enhance one another's de novo appearance. Here we show that specific prion variants of [PSI+] and [PIN+] disrupt each other's stable inheritance. Acquiring [PSI+] often impedes the inheritance of particular [PIN+] variants. Conversely, the presence of some [PIN+] variants impairs the inheritance of weak [PSI+] but not strong [PSI+] variants. These same [PIN+] variants generate a single-dot fluorescence pattern when a fusion of Rnq1 and green fluorescent protein is expressed. Another [PIN+] variant, which forms a distinctly different multiple-dot fluorescence pattern, does not impair [PSI+] inheritance. Thus, destabilization of prions by heterologous prions depends upon the variants involved. These findings may have implications for understanding interactions among other amyloid-forming proteins, including those associated with certain human diseases. PMID:14704158

  6. Origin of pinning enhancement in a ferromagnet-superconductor bilayer

    NASA Astrophysics Data System (ADS)

    Cieplak, Marta Z.; Cheng, X. M.; Chien, C. L.; Sang, Hai

    2005-01-01

    Vortex pinning has been studied for the superconducting Nb film covering ferromagnetic Co /Pt multilayer with perpendicular magnetic anisotropy, in which the magnetization reversal proceeds via domain-wall motion. Large enhancement of pinning in the Nb film has been observed in the final stages of the reversal process, and we demonstrate that it is caused by residual uninverted dendrite-shaped magnetic domains.

  7. Prefoldin and Pins synergistically regulate asymmetric division and suppress dedifferentiation

    PubMed Central

    Zhang, Yingjie; Rai, Madhulika; Wang, Cheng; Gonzalez, Cayetano; Wang, Hongyan

    2016-01-01

    Prefoldin is a molecular chaperone complex that regulates tubulin function in mitosis. Here, we show that Prefoldin depletion results in disruption of neuroblast polarity, leading to neuroblast overgrowth in Drosophila larval brains. Interestingly, co-depletion of Prefoldin and Partner of Inscuteable (Pins) leads to the formation of gigantic brains with severe neuroblast overgrowth, despite that Pins depletion alone results in smaller brains with partially disrupted neuroblast polarity. We show that Prefoldin acts synergistically with Pins to regulate asymmetric division of both neuroblasts and Intermediate Neural Progenitors (INPs). Surprisingly, co-depletion of Prefoldin and Pins also induces dedifferentiation of INPs back into neuroblasts, while depletion either Prefoldin or Pins alone is insufficient to do so. Furthermore, knocking down either α-tubulin or β-tubulin in pins- mutant background results in INP dedifferentiation back into neuroblasts, leading to the formation of ectopic neuroblasts. Overexpression of α-tubulin suppresses neuroblast overgrowth observed in prefoldin pins double mutant brains. Our data elucidate an unexpected function of Prefoldin and Pins in synergistically suppressing dedifferentiation of INPs back into neural stem cells. PMID:27025979

  8. Semiconductor P-I-N detector

    SciTech Connect

    Sudharsanan, Rengarajan; Karam, Nasser H.

    2001-01-01

    A semiconductor P-I-N detector including an intrinsic wafer, a P-doped layer, an N-doped layer, and a boundary layer for reducing the diffusion of dopants into the intrinsic wafer. The boundary layer is positioned between one of the doped regions and the intrinsic wafer. The intrinsic wafer can be composed of CdZnTe or CdTe, the P-doped layer can be composed of ZnTe doped with copper, and the N-doped layer can be composed of CdS doped with indium. The boundary layers is formed of an undoped semiconductor material. The boundary layer can be deposited onto the underlying intrinsic wafer. The doped regions are then typically formed by a deposition process or by doping a section of the deposited boundary layer.

  9. Cracking Bank PINs by Playing Mastermind

    NASA Astrophysics Data System (ADS)

    Focardi, Riccardo; Luccio, Flaminia L.

    The bank director was pretty upset noticing Joe, the system administrator, spending his spare time playing Mastermind, an old useless game of the 70ies. He had fought the instinct of telling him how to better spend his life, just limiting to look at him in disgust long enough to be certain to be noticed. No wonder when the next day the director fell on his chair astonished while reading, on the newspaper, about a huge digital fraud on the ATMs of his bank, with millions of Euros stolen by a team of hackers all around the world. The article mentioned how the hackers had 'played with the bank computers just like playing Mastermind', being able to disclose thousands of user PINs during the one-hour lunch break. That precise moment, a second before falling senseless, he understood the subtle smile on Joe's face the day before, while training at his preferred game, Mastermind.

  10. Pin stack array for thermoacoustic energy conversion

    DOEpatents

    Keolian, Robert M.; Swift, Gregory W.

    1995-01-01

    A thermoacoustic stack for connecting two heat exchangers in a thermoacoustic energy converter provides a convex fluid-solid interface in a plane perpendicular to an axis for acoustic oscillation of fluid between the two heat exchangers. The convex surfaces increase the ratio of the fluid volume in the effective thermoacoustic volume that is displaced from the convex surface to the fluid volume that is adjacent the surface within which viscous energy losses occur. Increasing the volume ratio results in an increase in the ratio of transferred thermal energy to viscous energy losses, with a concomitant increase in operating efficiency of the thermoacoustic converter. The convex surfaces may be easily provided by a pin array having elements arranged parallel to the direction of acoustic oscillations and with effective radial dimensions much smaller than the thicknesses of the viscous energy loss and thermoacoustic energy transfer volumes.

  11. Nb-Ti composite wires with artificial ferromagnetic pins

    SciTech Connect

    Cooley, L.D.; Jablonski, P.D.; Heussner, R.W.

    1997-06-01

    Flux-pinning data for Nb47Ti/Fe and Nb55Ti/Ni composites indicate that ferromagnets pin by a barrier mechanism similar to the mechanism studied by Clem for superconductor/insulator multilayers. However, in contrast to Clem`s model, the optimum pin separation should be rather large, because at smaller pin separations the condition {vert_bar}{psi}{vert_bar}{sup 2} = 0 at the superconductor/ferromagnet interface leads to a reduction of T{sub c} and H{sub c2}. Nonetheless, the authors find no indication in the experimental data that pin separations much smaller than the predicted optimum value adversely affect J{sub c}, T{sub c}, or H{sub c2}.

  12. Retrievable fuel pin end member for a nuclear reactor

    DOEpatents

    Rosa, Jerry M.

    1982-01-01

    A bottom end member (17b) on a retrievable fuel pin (13b) secures the pin (13b) within a nuclear reactor (12) by engaging on a transverse attachment rail (18) with a spring clip type of action. Removal and reinstallation if facilitated as only axial movement of the fuel pin (13b) is required for either operation. A pair of resilient axially extending blades (31) are spaced apart to define a slot (24) having a seat region (34) which receives the rail (18) and having a land region (37), closer to the tips (39) of the blades (31) which is normally of less width than the rail (18). Thus an axially directed force sufficient to wedge the resilient blades (31) apart is required to emplace or release the fuel pin (13b) such force being greater than the axial forces on the fuel pins (13b) which occur during operation of the reactor (12).

  13. Spatial homogenization methods for pin-by-pin neutron transport calculations

    NASA Astrophysics Data System (ADS)

    Kozlowski, Tomasz

    For practical reactor core applications low-order transport approximations such as SP3 have been shown to provide sufficient accuracy for both static and transient calculations with considerably less computational expense than the discrete ordinate or the full spherical harmonics methods. These methods have been applied in several core simulators where homogenization was performed at the level of the pin cell. One of the principal problems has been to recover the error introduced by pin-cell homogenization. Two basic approaches to treat pin-cell homogenization error have been proposed: Superhomogenization (SPH) factors and Pin-Cell Discontinuity Factors (PDF). These methods are based on well established Equivalence Theory and Generalized Equivalence Theory to generate appropriate group constants. These methods are able to treat all sources of error together, allowing even few-group diffusion with one mesh per cell to reproduce the reference solution. A detailed investigation and consistent comparison of both homogenization techniques showed potential of PDF approach to improve accuracy of core calculation, but also reveal its limitation. In principle, the method is applicable only for the boundary conditions at which it was created, i.e. for boundary conditions considered during the homogenization process---normally zero current. Therefore, there exists a need to improve this method, making it more general and environment independent. The goal of proposed general homogenization technique is to create a function that is able to correctly predict the appropriate correction factor with only homogeneous information available, i.e. a function based on heterogeneous solution that could approximate PDFs using homogeneous solution. It has been shown that the PDF can be well approximated by least-square polynomial fit of non-dimensional heterogeneous solution and later used for PDF prediction using homogeneous solution. This shows a promise for PDF prediction for off

  14. Retractable Pin Tools for the Friction Stir Welding Process

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Two companies have successfully commercialized a specialized welding tool developed at the Marshall Space Flight Center (MSFC). Friction stir welding uses the high rotational speed of a tool and the resulting frictional heat created from contact to crush, 'stir' together, and forge a bond between two metal alloys. It has had a major drawback, reliance on a single-piece pin tool. The pin is slowly plunged into the joint between two materials to be welded and rotated as high speed. At the end of the weld, the single-piece pin tool is retracted and leaves a 'keyhole,' something which is unacceptable when welding cylindrical objects such as drums, pipes and storage tanks. Another drawback is the requirement for different-length pin tools when welding materials of varying thickness. An engineer at the MSFC helped design an automatic retractable pin tool that uses a computer-controlled motor to automatically retract the pin into the shoulder of the tool at the end of the weld, preventing keyholes. This design allows the pin angle and length to be adjusted for changes in material thickness and results in a smooth hole closure at the end of the weld. Benefits of friction stir welding, using the MSFC retractable pin tool technology, include the following: The ability to weld a wide range of alloys, including previously unweldable and composite materials; provision of twice the fatigue resistance of fusion welds and no keyholes; minimization of material distortion; no creation of hazards such as welding fumes, radiation, high voltage, liquid metals, or arcing; automatic retraction of the pin at the end of the weld; and maintaining full penetration of the pin.

  15. Three-dimensional pin-to-pin analyses of VVER-440 cores by the MOBY-DICK code

    SciTech Connect

    Lehmann, M.; Mikolas, P.

    1994-12-31

    Nuclear design for the Dukovany (EDU) VVER-440s nuclear power plant is routinely performed by the MOBY-DICK system. After its implementation on Hewlett Packard series 700 workstations, it is able to perform routinely three-dimensional pin-to-pin core analyses. For purposes of code validation, the benchmark prepared from EDU operational data was solved.

  16. The Puzzling Ophiuchus Stream

    NASA Astrophysics Data System (ADS)

    Kohler, Susanna

    2016-01-01

    Dwarf galaxies or globular clusters orbiting the Milky Way can be pulled apart by tidal forces, leaving behind a trail of stars known as a stellar stream. One such trail, the Ophiuchus stream, has posed a serious dynamical puzzle since its discovery. But a recent study has identified four stars that might help resolve this streams mystery.Conflicting TimescalesThe stellar stream Ophiuchus was discovered around our galaxy in 2014. Based on its length, which appears to be 1.6 kpc, we can calculate the time that has passed since its progenitor was disrupted and the stream was created: ~250 Myr. But the stars within it are ~12 Gyr old, and the stream orbits the galaxy with a period of ~350 Myr.Given these numbers, we can assume that Ophiuchuss progenitor completed many orbits of the Milky Way in its lifetime. So why would it only have been disrupted 250 million years ago?Fanning StreamLed by Branimir Sesar (Max Planck Institute for Astronomy), a team of scientists has proposed an idea that might help solve this puzzle. If the Ophiuchus stellar stream is on a chaotic orbit common in triaxial potentials, which the Milky Ways may be then the stream ends can fan out, with stars spreading in position and velocity.The fanned part of the stream, however, would be difficult to detect because of its low surface brightness. As a result, the Ophiuchus stellar stream could actually be longer than originally measured, implying that it was disrupted longer ago than was believed.Search for Fan StarsTo test this idea, Sesar and collaborators performed a search around the ends of the stream, looking for stars thatare of the right type to match the stream,are at the predicted distance of the stream,are located near the stream ends, andhave velocities that match the stream and dont match the background halo stars.Histogram of the heliocentric velocities of the 43 target stars. Six stars have velocities matching the stream velocity. Two of these are located in the main stream; the other

  17. Gas stream purifier

    NASA Technical Reports Server (NTRS)

    Adam, Steven J.

    1994-01-01

    A gas stream purifier has been developed that is capable of removing corrosive acid, base, solvent, organic, inorganic, and water vapors as well as particulates from an inert mixed gas stream using only solid scrubbing agents. This small, lightweight purifier has demonstrated the ability to remove contaminants from an inert gas stream with a greater than 99 percent removal efficiency. The Gas Stream Purifier has outstanding market and sales potential in manufacturing, laboratory and science industries, medical, automotive, or any commercial industry where pollution, contamination, or gas stream purification is a concern. The purifier was developed under NASA contract NAS9-18200 Schedule A for use in the international Space Station. A patent application for the Gas Stream Purifier is currently on file with the United States Patent and Trademark Office.

  18. User aware video streaming

    NASA Astrophysics Data System (ADS)

    Kerofsky, Louis; Jagannath, Abhijith; Reznik, Yuriy

    2015-03-01

    We describe the design of a video streaming system using adaptation to viewing conditions to reduce the bitrate needed for delivery of video content. A visual model is used to determine sufficient resolution needed under various viewing conditions. Sensors on a mobile device estimate properties of the viewing conditions, particularly the distance to the viewer. We leverage the framework of existing adaptive bitrate streaming systems such as HLS, Smooth Streaming or MPEG-DASH. The client rate selection logic is modified to include a sufficient resolution computed using the visual model and the estimated viewing conditions. Our experiments demonstrate significant bitrate savings compare to conventional streaming methods which do not exploit viewing conditions.

  19. Inventory of miscellaneous streams

    SciTech Connect

    Lueck, K.J.

    1995-09-01

    On December 23, 1991, the US Department of Energy, Richland Operations Office (RL) and the Washington State Department of Ecology (Ecology) agreed to adhere to the provisions of the Department of Ecology Consent Order. The Consent Order lists the regulatory milestones for liquid effluent streams at the Hanford Site to comply with the permitting requirements of Washington Administrative Code. The RL provided the US Congress a Plan and Schedule to discontinue disposal of contaminated liquid effluent into the soil column on the Hanford Site. The plan and schedule document contained a strategy for the implementation of alternative treatment and disposal systems. This strategy included prioritizing the streams into two phases. The Phase 1 streams were considered to be higher priority than the Phase 2 streams. The actions recommended for the Phase 1 and 2 streams in the two reports were incorporated in the Hanford Federal Facility Agreement and Consent Order. Miscellaneous Streams are those liquid effluents streams identified within the Consent Order that are discharged to the ground but are not categorized as Phase 1 or Phase 2 Streams. This document consists of an inventory of the liquid effluent streams being discharged into the Hanford soil column.

  20. Dynamics of meteor streams

    NASA Technical Reports Server (NTRS)

    Babadjanov, P. B.; Obrubov, Yu. U.

    1987-01-01

    The overwhelming majority of meteor streams are generally assumed to be formed due to the decay of comets. The most effective process of the release of solid particles from a cometary nucleus is their ejection by sublimating gases when the comet approaches the Sun. The results of investigation of the Geminids and Quadrantids meteor stream evolution show that under the influence of planetary perturbations, the stream may originally be flat but then thicken depending on the variation range of orbital inclinations. Eventually, due to planetary perturbations, a meteor stream may take such a shape as to cause the start of several active showers at different solar longitudes.

  1. Domain wall pinning for racetrack memory using exchange bias

    NASA Astrophysics Data System (ADS)

    Polenciuc, I.; Vick, A. J.; Allwood, D. A.; Hayward, T. J.; Vallejo-Fernandez, G.; O'Grady, K.; Hirohata, A.

    2014-10-01

    The pinning of domain walls in ferromagnetic (F) wires is one possible technique for the creation of a solid state magnetic memory. Such a system has been under consideration for some time but one of the main limitations is the control of, and non-uniformity of the domain wall pinning. Techniques such as the lithographic definition of notches and steps in the substrate have had some success in creating local pins but have the disadvantage of being expensive to fabricate and the reproducibility of the domain wall pinning strength is limited. In this letter, we report on an alternative strategy to create pins of reproducible strength using crossed ferromagnetic and antiferromagnetic (AF) wires such that exchange bias can be introduced at the crossing points. Such a system has the advantage of ease of fabrication and creating domain wall pins of controlled strength by varying the width of the AF wire. We have achieved domain wall pinning field strengths of up to 37 Oe in a system where the AF wire is deposited above the F wire which is comparable to the values achieved using notches.

  2. Dynamics of Glass Forming Liquids with Randomly Pinned Particles

    PubMed Central

    Chakrabarty, Saurish; Karmakar, Smarajit; Dasgupta, Chandan

    2015-01-01

    It is frequently assumed that in the limit of vanishing cooling rate, the glass transition phenomenon becomes a thermodynamic transition at a temperature TK. However, with any finite cooling rate, the system falls out of equilibrium at temperatures near Tg(>TK), implying that the very existence of the putative thermodynamic phase transition at TK can be questioned. Recent studies of systems with randomly pinned particles have hinted that the thermodynamic glass transition may be observed for liquids with randomly pinned particles. This expectation is based on the results of approximate calculations that suggest that the thermodynamic glass transition temperature increases with increasing concentration of pinned particles and it may be possible to equilibrate the system at temperatures near the increased transition temperature. We test the validity of this prediction through extensive molecular dynamics simulations of two model glass-forming liquids in the presence of random pinning. We find that extrapolated thermodynamic transition temperature TK does not show any sign of increasing with increasing pinning concentration. The main effect of pinning is found to be a rapid decrease in the kinetic fragility of the system with increasing pin concentration. Implications of these observations for current theories of the glass transition are discussed. PMID:26206070

  3. Flux pinning by grain boundaries in A15 superconductors

    SciTech Connect

    Welch, D.O.; Suenaga, M.; Snead, C.L. Jr.; Hatcher, R.D.

    1985-01-01

    The form of the scaling law for flux pinning by grain boundaries in A15-structure compounds, primarily in the case of Nb3Sn and its alloys, is discussed, and the effect of alloying and radiation damage on the pinning strength is compared with predictions of the electron-scattering theory of the elementary pinning force. In addition, some preliminary results of 2-dimensional computer simulations are discussed in relation to the observed effects of alloying on the form of the scaling law for Nb3Sn.

  4. Flux Pinning in the Superconducting Phases of UPt_3

    NASA Astrophysics Data System (ADS)

    Shung, Emmin; Rosenbaum, Thomas F.

    1997-03-01

    We examine the effectiveness of bulk and surface pinning in the superconducting phases of UPt_3. Using high resolution Hall probe arrays, we measure locally the magnetization hysteresis and relaxation in a single crystal torus. The toroidal topology allows us to distinguish surface and bulk pinning effects by measuring the local magnetization over the hole, the bulk, and the interface. By comparing field cooled and zero field cooled measurements, we attempt to correlate the changes in flux pinning with the transition between the two superconducting phases. (R. J. Zieve et. al., Phys. Rev. B51), 12041 (1995)

  5. An Accelerated Method for Testing Soldering Tendency of Core Pins

    SciTech Connect

    Han, Qingyou; Xu, Hanbing; Ried, Paul; Olson, Paul

    2010-01-01

    An accelerated method for testing die soldering has been developed. High intensity ultrasonic vibrations has been used to simulate the die casting conditions such as high pressure and high impingement speed of molten metal on the pin. Soldering tendency of steels and coated pins has been examined. The results indicate that in the low carbon steel/Al system, the onset of soldering is 60 times faster with ultrasonic vibration than that without ultrasonic vibration. In the H13/A380 system, the onset of soldering reaction is accelerated to 30-60 times. Coating significantly reduces the soldering tendency of the core pins.

  6. Fabrication of oxide dispersion strengthened ferritic clad fuel pins

    SciTech Connect

    Zirker, L.R. ); Bottcher, J.H. ); Shikakura, S. ); Tsai, C.L. . Dept. of Welding Engineering); Hamilton, M.L. )

    1991-01-01

    A resistance butt welding procedure was developed and qualified for joining ferritic fuel pin cladding to end caps. The cladding are INCO MA957 and PNC ODS lots 63DSA and 1DK1, ferritic stainless steels strengthened by oxide dispersion, while the end caps are HT9 a martensitic stainless steel. With adequate parameter control the weld is formed without a residual melt phase and its strength approaches that of the cladding. This welding process required a new design for fuel pin end cap and weld joint. Summaries of the development, characterization, and fabrication processes are given for these fuel pins. 13 refs., 6 figs., 1 tab.

  7. Pinning Control in a System of Mobile Chaotic Oscillators

    NASA Astrophysics Data System (ADS)

    Dariani, Reza; Buscarino, Arturo; Fortuna, Luigi; Frasca, Mattia

    2011-09-01

    In this paper, pinning control in a system of moving agents (each one associated to a chaotic dynamical system) has been investigated. In particular, we have studied and compared two different strategies for pinning control and discussed the not trivial relation between synchronization and control of the chaotic agents. Our results show how system parameters like agent density are critical in order to reach a synchronous behavior of the agents as well as to reach global control of the system by only pinning a reduced set of agents.

  8. Three-Dimensional Prints with Pinned Cylindrical Lens Arrays

    NASA Astrophysics Data System (ADS)

    Yasuda, Shin; Shimizu, Keishi

    2013-09-01

    An application of pinned cylindrical lens arrays (CLAs) reported in Opt. Rev. 19 (2012) 287 to three-dimensional prints is presented for the first time. This lens fabrication method features the easy control of the pitch and radius of curvature of the lens arrays by taking advantage of the pinning effect that the partition walls created on a polymeric substrate by scratching with a cutter blade prevent the ultraviolet curable polymer dispensed between the walls from spreading. It is demonstrated in this paper that a three-dimensional print was realized successfully with the pinned CLA fabricated with our method.

  9. Equilibrium ultrastable glasses produced by random pinning

    SciTech Connect

    Hocky, Glen M.; Reichman, David R.; Berthier, Ludovic

    2014-12-14

    Ultrastable glasses have risen to prominence due to their potentially useful material properties and the tantalizing possibility of a general method of preparation via vapor deposition. Despite the importance of this novel class of amorphous materials, numerical studies have been scarce because achieving ultrastability in atomistic simulations is an enormous challenge. Here, we bypass this difficulty and establish that randomly pinning the position of a small fraction of particles inside an equilibrated supercooled liquid generates ultrastable configurations at essentially no numerical cost, while avoiding undesired structural changes due to the preparation protocol. Building on the analogy with vapor-deposited ultrastable glasses, we study the melting kinetics of these configurations following a sudden temperature jump into the liquid phase. In homogeneous geometries, we find that enhanced kinetic stability is accompanied by large scale dynamic heterogeneity, while a competition between homogeneous and heterogeneous melting is observed when a liquid boundary invades the glass at constant velocity. Our work demonstrates the feasibility of large-scale, atomistically resolved, and experimentally relevant simulations of the kinetics of ultrastable glasses.

  10. Multi-pin chemiresistors for microchemical sensors

    DOEpatents

    Ho, Clifford K.

    2007-02-20

    A multi-pin chemiresistor for use in microchemical sensors. A pair of free-standing, bare wires is supported by an electrically insulating support, and are oriented parallel to each other and spaced closely together. A free-standing film of a chemically sensitive polymer that swells when exposed to vapors of a volatile chemical is formed in-between the pair of closely-spaced wires by capillary action. Similar in construction to a thermocouple, this "chemicouple" is relatively inexpensive and easy to fabricate by dipping the pair of bare wires into a bath of well-mixed chemiresistor ink. Also, a chemiresistor "stick" is formed by dipping an electrically insulating rod with two or more linear or spiral-wrapped electrical traces into the bath of well-mixed chemiresistor ink, which deposits a uniform coating of the chemically sensitive polymer on the rod and the electrical traces. These "sticks" can be easily removed and replaced from a multi-chemiresistor plug.

  11. Pinning of Austenite Grain Boundaries by

    NASA Astrophysics Data System (ADS)

    Doğan, Ömer N.; Michal, G. M.; Kwon, H.-W.

    1992-08-01

    The growth behavior of austenite grains in the presence of A1N precipitates varies with the temperature and time of anneal. To study this behavior, two iron alloys, (in weight percent) a 0.1 carbon base chemistry with 0.03A1/0.01N and 0.09A1/0.04N, respectively, were annealed between 1000 °C and 1200 °C for times of up to 180 minutes. Using optical microscopy, as many as 1000 austenite grains per heat-treatment condition were measured. Conditions of sup- pressed, abnormal, and uniform grain growth were observed. Using an extraction replica tech- nique, the size, shape, and distribution of the A1N particles were determined using transmission electron microscopy (TEM). The largest grain boundary curvatures calculated, using the Hellman- Hillert pinning model, were in close agreement with independent calculations of curvatures using the grain size data. The largest grains in the lognormal size distribution of austenite grains were found to be the ones with the potential to grow to abnormally large sizes.

  12. Superconducting vortex pinning with artificial magnetic nanostructures.

    SciTech Connect

    Velez, M.; Martin, J. I.; Villegas, J. E.; Hoffmann, A.; Gonzalez, E. M.; Vicent, J. L.; Schuller, I. K.; Univ. de Oviedo-CINN; Unite Mixte de Physique CNRS Univ. Paris-Sud; Univ.Complutense de Madrid; Univ. California at San Diego

    2008-11-01

    This review is dedicated to summarizing the recent research on vortex dynamics and pinning effects in superconducting films with artificial magnetic structures. The fabrication of hybrid superconducting/magnetic systems is presented together with the wide variety of properties that arise from the interaction between the superconducting vortex lattice and the artificial magnetic nanostructures. Specifically, we review the role that the most important parameters in the vortex dynamics of films with regular array of dots play. In particular, we discuss the phenomena that appear when the symmetry of a regular dot array is distorted from regularity towards complete disorder including rectangular, asymmetric, and aperiodic arrays. The interesting phenomena that appear include vortex-lattice reconfigurations, anisotropic dynamics, channeling, and guided motion as well as ratchet effects. The different regimes are summarized in a phase diagram indicating the transitions that take place as the characteristic distances of the array are modified respect to the superconducting coherence length. Future directions are sketched out indicating the vast open area of research in this field.

  13. Adopt a Stream.

    ERIC Educational Resources Information Center

    Friends of Environmental Education Society of Alberta (Edmonton).

    This environmental education program is designed to increase awareness among junior high school students of stream ecosystems and those habitats which comprise the ecosystems adjacent to streams. The teaching content of the manual is presented in two major sections. The first section provides information and background material for the group…

  14. Citrus waste stream utilization

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Waste streams, generated during fruit processing, consist of solid fruit residues in addition to liquid waste streams from washing operations which must be handled in an environmentally acceptable manner. Unsound fruit from packing houses are usually sent off to be processed for juice and the solid ...

  15. MARYLAND BIOLOGICAL STREAM SURVEY

    EPA Science Inventory

    The Maryland Biological Stream Survey (MBSS) is a multi-year probability-based sampling program designed to assess the status of biological resources in non-tidal streams of Maryland. The MBSS is quantifying the extent to which acidic deposition and other human activities have af...

  16. River and Stream Pollution

    MedlinePlus

    ... Pollution Dirt Dirt is a big cause of pollution in our rivers and streams. Rain washes dirt into streams and rivers. Dirt can smother fish and other animals that live in the water. If plants can't get enough sunlight because ...

  17. WADEABLE STREAMS ASSESSMENT

    EPA Science Inventory

    This Wadeable Streams Assessment (WSA) provides the first statistically defensible summary of the condition of the nation’s streams and small rivers, which are so integrally tied to our history. This report brings the results of this ground-breaking study to the American public....

  18. Ramification of stream networks

    PubMed Central

    Devauchelle, Olivier; Petroff, Alexander P.; Seybold, Hansjörg F.; Rothman, Daniel H.

    2012-01-01

    The geometric complexity of stream networks has been a source of fascination for centuries. However, a comprehensive understanding of ramification—the mechanism of branching by which such networks grow—remains elusive. Here we show that streams incised by groundwater seepage branch at a characteristic angle of 2π/5 = 72°. Our theory represents streams as a collection of paths growing and bifurcating in a diffusing field. Our observations of nearly 5,000 bifurcated streams growing in a 100 km2 groundwater field on the Florida Panhandle yield a mean bifurcation angle of 71.9° ± 0.8°. This good accord between theory and observation suggests that the network geometry is determined by the external flow field but not, as classical theories imply, by the flow within the streams themselves. PMID:23223562

  19. 9. FINIAL DETAIL COVERING PIN CONNECTIONS AND COMPRESSION BLOCK AT ...

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

    9. FINIAL DETAIL COVERING PIN CONNECTIONS AND COMPRESSION BLOCK AT EAST INCLINED END POST. NOTE CONSTRUCTION DATE OF 1880. - Peevy Road Bridge, Peevy Road spanning Perkiomen Creek in Upper Hanover Township, East Greenville, Montgomery County, PA

  20. 20. LOCK GATES, 3 FOOT WALKWAY, ADJUSTMENT AT GUDGEON PIN ...

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

    20. LOCK GATES, 3 FOOT WALKWAY, ADJUSTMENT AT GUDGEON PIN AND QUOIN SHOE. May 1933 - Mississippi River 9-Foot Channel Project, Lock & Dam No. 17, Upper Mississippi River, New Boston, Mercer County, IL

  1. 43. DETAIL OF PINNED UPPER CHORD CONNECTION BETWEEN ANCHOR ARM ...

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

    43. DETAIL OF PINNED UPPER CHORD CONNECTION BETWEEN ANCHOR ARM AND SUSPENDED (PANEL 67). VIEW TO NORTH. - Blue Water Bridge, Spanning St. Clair River at I-69, I-94, & Canadian Route 402, Port Huron, St. Clair County, MI

  2. 4. DETAIL OF PIN CONNECTION ON SOUTH SIDE. North ...

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

    4. DETAIL OF PIN CONNECTION ON SOUTH SIDE. - North Branch Quantico Creek Bridge, Prince William Forest Park, on NPS Route 406 spanning north branch of Quantico Creek, Dumfries, Prince William County, VA

  3. 7. DETAIL VIEW OF PIN CONNECTION, NORTH WEB, SHOWING FLOOR ...

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

    7. DETAIL VIEW OF PIN CONNECTION, NORTH WEB, SHOWING FLOOR BEANS, STRINGERS, LATTICE BRACING, EYEBARS AND DECKING, LOOKING SOUTH - Four Mile Bridge, Spanning Elk River on County Road 42, Steamboat Springs, Routt County, CO

  4. 9. Detail view (looking east) of pin connection of vertical ...

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

    9. Detail view (looking east) of pin connection of vertical tensile members at the fifth panel point north from south abutment of Moody Bridge. - Moody Bridge, Spanning South Fork Eel River, Garberville, Humboldt County, CA

  5. 11. Detail view (looking east) of pin connection of vertical ...

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

    11. Detail view (looking east) of pin connection of vertical tensile members between panels nine end ten of Moody Bridge - Moody Bridge, Spanning South Fork Eel River, Garberville, Humboldt County, CA

  6. 8. Detail view (looking east) of pin connection of vertical ...

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

    8. Detail view (looking east) of pin connection of vertical member at the third panel point north from south abutment of Moody Bridge. - Moody Bridge, Spanning South Fork Eel River, Garberville, Humboldt County, CA

  7. Pinned orbital moments – A new contribution to magnetic anisotropy

    NASA Astrophysics Data System (ADS)

    Audehm, P.; Schmidt, M.; Brück, S.; Tietze, T.; Gräfe, J.; Macke, S.; Schütz, G.; Goering, E.

    2016-05-01

    Reduced dimensionality and symmetry breaking at interfaces lead to unusual local magnetic configurations, such as glassy behavior, frustration or increased anisotropy. The interface between a ferromagnet and an antiferromagnet is such an example for enhanced symmetry breaking. Here we present detailed X-ray magnetic circular dichroism and X-ray resonant magnetic reflectometry investigations on the spectroscopic nature of uncompensated pinned magnetic moments in the antiferromagnetic layer of a typical exchange bias system. Unexpectedly, the pinned moments exhibit nearly pure orbital moment character. This strong orbital pinning mechanism has not been observed so far and is not discussed in literature regarding any theory for local magnetocrystalline anisotropy energies in magnetic systems. To verify this new phenomenon we investigated the effect at different temperatures. We provide a simple model discussing the observed pure orbital moments, based on rotatable spin magnetic moments and pinned orbital moments on the same atom. This unexpected observation leads to a concept for a new type of anisotropy energy.

  8. Pinning and movement of individual nanoscale magnetic skyrmions via defects

    NASA Astrophysics Data System (ADS)

    Hanneken, Christian; Kubetzka, André; von Bergmann, Kirsten; Wiesendanger, Roland

    2016-05-01

    An understanding of the pinning of magnetic skyrmions to defects is crucial for the development of future spintronic applications. While pinning is desirable for a precise positioning of magnetic skyrmions it is detrimental when they are to be moved through a material. We use scanning tunneling microscopy (STM) to study the interaction between atomic scale defects and magnetic skyrmions that are only a few nanometers in diameter. The studied pinning centers range from single atom inlayer defects and adatoms to clusters adsorbed on the surface of our model system. We find very different pinning strengths and identify preferred positions of the skyrmion. The interaction between a cluster and a skyrmion can be sufficiently strong for the skyrmion to follow when the cluster is moved across the surface by lateral manipulation with the STM tip.

  9. 13. UNDERSIDE OF THROUGHWAY SHOWING MAIN CHORDS, SUSPENSION EYEBAR PIN ...

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

    13. UNDERSIDE OF THROUGHWAY SHOWING MAIN CHORDS, SUSPENSION EYE-BAR PIN CONNECTORS, LOWER CHORD EYEBARS AND LATERAL BRACING MEMBERS - Spruce Street Bridge, East Spruce Street, 500 Block, spanning Power Canal, Sault Ste. Marie, Chippewa County, MI

  10. 10. EYEBAR PIN CONNECTION JOINING VERTICAL SUSPENSION STRINGER WITH LATERAL ...

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

    10. EYEBAR PIN CONNECTION JOINING VERTICAL SUSPENSION STRINGER WITH LATERAL BRACING MEMBERS - Spruce Street Bridge, East Spruce Street, 500 Block, spanning Power Canal, Sault Ste. Marie, Chippewa County, MI

  11. 22. DETAIL VIEW OF NONSUBMERSIBLE TAINTER GATE, SHOWING TRUNNION PIN, ...

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

    22. DETAIL VIEW OF NONSUBMERSIBLE TAINTER GATE, SHOWING TRUNNION PIN, GATE ARM AND GATE GAUGE, LOOKING NORTHWEST - Upper Mississippi River 9-Foot Channel, Lock & Dam No. 10, Guttenberg, Clayton County, IA

  12. SP-100 fuel pin performance: Results from irradiation testing

    SciTech Connect

    Makenas, B.J.; Paxton, D.M.; Vaidyanathan, S.; Hoth, C.W.

    1993-09-01

    A total of 86 experimental fuel pins with various fuel, liner, and cladding candidate materials have been irradiated in the Experimental Breeder Reactor-II (EBR-II) and the Fast Flux Test Facility (FFTF) reactor as part of the SP-100 fuel pin irradiation testing program. Postirradiation examination results from these fuel pin are key in establishing performance correlations and demonstrating the lifetime and safety of the reactor fuel system. This paper provides a brief description of the in-reactor fuel pin tests and presents the most recent irradiation data on the performance of wrought rhenium (Re) liner material and high density UN fuel at goal burnup of 6 atom percent (at. %). It also provides an overview of the significant variety of other fuel/liner/cladding combinations which were irradiated as part of this program and which may be of interest to more advanced efforts.

  13. 8. Pin connecting and eye bar nest, lower chord, down ...

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

    8. Pin connecting and eye bar nest, lower chord, down river truss 132-0 Span 2 from Hot Metal Bridge. - Monongahela Connecting Railroad Company, Main Bridge, Spanning Monongahela River at mile post 3.1, Pittsburgh, Allegheny County, PA

  14. 7. Pin connections and eye bar nest, lower chord, up ...

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

    7. Pin connections and eye bar nest, lower chord, up river truss, 321-4 Span 3. - Monongahela Connecting Railroad Company, Main Bridge, Spanning Monongahela River at mile post 3.1, Pittsburgh, Allegheny County, PA

  15. 6. Pin connection and eye bar nest, lower chord, up ...

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

    6. Pin connection and eye bar nest, lower chord, up river truss, 321-4 Span 3. - Monongahela Connecting Railroad Company, Main Bridge, Spanning Monongahela River at mile post 3.1, Pittsburgh, Allegheny County, PA

  16. Pinning Susceptibility: The Effect of Dilute, Quenched Disorder on Jamming

    NASA Astrophysics Data System (ADS)

    Graves, Amy L.; Nashed, Samer; Padgett, Elliot; Goodrich, Carl P.; Liu, Andrea J.; Sethna, James P.

    2016-06-01

    We study the effect of dilute pinning on the jamming transition. Pinning reduces the average contact number needed to jam unpinned particles and shifts the jamming threshold to lower densities, leading to a pinning susceptibility, χp . Our main results are that this susceptibility obeys scaling form and diverges in the thermodynamic limit as χp∝|ϕ -ϕc∞|-γp where ϕc∞ is the jamming threshold in the absence of pins. Finite-size scaling arguments yield these values with associated statistical (systematic) errors γp=1.018 ±0.026 (0.291 ) in d =2 and γp=1.534 ±0.120 (0.822 ) in d =3 . Logarithmic corrections raise the exponent in d =2 to close to the d =3 value, although the systematic errors are very large.

  17. 22. PIN CONNECTION AT JUNCTURE OF INTERMEDIATE VERTICAL WITH BOTTOM ...

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

    22. PIN CONNECTION AT JUNCTURE OF INTERMEDIATE VERTICAL WITH BOTTOM CHORD ON PENNSYLVANIA PETIT TRUSS. HYDRAULICALLY FORGED EYES ON ROLLED STOCK. - New River Bridge, Spanning New River at State Route 623, Pembroke, Giles County, VA

  18. 21. DETAIL VIEW OF SUBMERSIBLE TAINTER GATE, SHOWING TRUNNION PIN, ...

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

    21. DETAIL VIEW OF SUBMERSIBLE TAINTER GATE, SHOWING TRUNNION PIN, LOOKING NORTH - Upper Mississippi River 9-Foot Channel, Lock & Dam No. 8, On Mississippi River near Houston County, MN, Genoa, Vernon County, WI

  19. 23. DETAIL VIEW OF SUBMERSIBLE TAINTER GATE, SHOWING TRUNNION PIN, ...

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

    23. DETAIL VIEW OF SUBMERSIBLE TAINTER GATE, SHOWING TRUNNION PIN, GATE ARM AND GATE GAUGE, LOOKING SOUTHEAST - Upper Mississippi River 9-Foot Channel, Lock & Dam No. 10, Guttenberg, Clayton County, IA

  20. 10. DETAIL VIEW OF PIN CONNECTION, SOUTH WEB, SHOWING TOP ...

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

    10. DETAIL VIEW OF PIN CONNECTION, SOUTH WEB, SHOWING TOP CHORD, INCLINED END POST, EYEBARS, AND PORTAL BRACING, LOOKING SOUTHWEST - Four Mile Bridge, Spanning Elk River on County Road 42, Steamboat Springs, Routt County, CO

  1. 11. VIEW OF PIN CONNECTION, SOUTH WEB, SHOWING TOP CHORD, ...

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

    11. VIEW OF PIN CONNECTION, SOUTH WEB, SHOWING TOP CHORD, LATTICE BRACING, HIP VERTICAL, EYEBARS, TOP LATERAL BRACING, AND STRUTS, LOOKING SOUTH - Four Mile Bridge, Spanning Elk River on County Road 42, Steamboat Springs, Routt County, CO

  2. Pinning impulsive directed coupled delayed dynamical network and its applications

    NASA Astrophysics Data System (ADS)

    Lin, Chunnan; Wu, Quanjun; Xiang, Lan; Zhou, Jin

    2015-01-01

    The main objective of the present paper is to further investigate pinning synchronisation of a complex delayed dynamical network with directionally coupling by a single impulsive controller. By developing the analysis procedure of pinning impulsive stability for undirected coupled dynamical network previously, some simple yet general criteria of pinning impulsive synchronisation for such directed coupled network are derived analytically. It is shown that a single impulsive controller can always pin a given directed coupled network to a desired homogenous solution, including an equilibrium point, a periodic orbit, or a chaotic orbit. Subsequently, the theoretical results are illustrated by a directed small-world complex network which is a cellular neural network (CNN) and a directed scale-free complex network with the well-known Hodgkin-Huxley neuron oscillators. Numerical simulations are finally given to demonstrate the effectiveness of the proposed control methodology.

  3. 24. PIN CONNECTION AT VERTICAL AND BOTTOM CHORD ON CAMELBACK ...

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

    24. PIN CONNECTION AT VERTICAL AND BOTTOM CHORD ON CAMELBACK THROUGH TRUSS. VERTICAL AND BOTTOM CHORD MADE OF HAND-FORGED EYE BARS - New River Bridge, Spanning New River at State Route 623, Pembroke, Giles County, VA

  4. Criteria for stochastic pinning control of networks of chaotic maps

    SciTech Connect

    Mwaffo, Violet; Porfiri, Maurizio; DeLellis, Pietro

    2014-03-15

    This paper investigates the controllability of discrete-time networks of coupled chaotic maps through stochastic pinning. In this control scheme, the network dynamics are steered towards a desired trajectory through a feedback control input that is applied stochastically to the network nodes. The network controllability is studied by analyzing the local mean square stability of the error dynamics with respect to the desired trajectory. Through the analysis of the spectral properties of salient matrices, a toolbox of conditions for controllability are obtained, in terms of the dynamics of the individual maps, algebraic properties of the network, and the probability distribution of the pinning control. We demonstrate the use of these conditions in the design of a stochastic pinning control strategy for networks of Chirikov standard maps. To elucidate the applicability of the approach, we consider different network topologies and compare five different stochastic pinning strategies through extensive numerical simulations.

  5. Procedure of recovery of pin-by-pin fields of energy release in the core of VVER-type reactor for the BIPR-8 code

    SciTech Connect

    Gordienko, P. V. Kotsarev, A. V.; Lizorkin, M. P.

    2014-12-15

    The procedure of recovery of pin-by-pin energy-release fields for the BIPR-8 code and the algorithm of the BIPR-8 code which is used in nodal computation of the reactor core and on which the recovery of pin-by-pin fields of energy release is based are briefly described. The description and results of the verification using the module of recovery of pin-by-pin energy-release fields and the TVS-M program are given.

  6. Ferromagnetic artificial pinning centers in superconducting niobium-titanium wires

    NASA Astrophysics Data System (ADS)

    Rizzo, Nicholas David

    1997-09-01

    Ferromagnetic artificial pinning centers were used in superconducting NbTi wires to achieve a large critical current density (Jsb{c}) in a magnetic field. The wire processing was developed to make four wires that contained nanometer-sized arrays of Ni or Fe pins inside micron-sized filaments of a Nbsb{0.36}Tiosb{0.64} alloy. The optimum pin size and spacing for maximum Jsb{c} was approximately 5 nm and 30 nm, respectively. A ferromagnetic pin volume of only 2% Ni produced Jsb{c}'s (e.g., 2500 A/mmsp2 at 5 T, 4.2 K) that were comparable to those of other NbTi wires that have pin volumes ranging from 12% to 20%. Therefore, ferromagnetic artificial pins are more effective than nonmagnetic pins for a given volume percent. Saturation Magnetization measurements on the wires showed a correlation between an increase in the amount of Ni remaining ferromagnetic in the wires and an increase in Jsb{c}. These results suggest wires with larger volumes of Ni may have even higher Jsb{c}'s. The critical temperature (Tsb{c}) of the best wire with Ni pins was only slightly depressed (Tsb{c}≈8.6 K) from the measured bulk value for Nbsb{0.36}Tiosb{0.64} (Tsb{c}≈9 K), suggesting that proximity effects from the Ni are not severe. Wires with small superconducting filament diameters (0.3 mum) displayed enhanced Jsb{c} at low fields (B ≤ 5 T) that was attributed to pinning at the filament surfaces. Finally, for wires with large filaments, the optimum bulk pinning force (Fsb{p}) dependence on B was well described by the form Fsb{p}~ bsp{1/2}(1-b) where b = B/Hsb{c2} and Hsb{c2} is the upper critical field of the superconductor. This form is interpreted as a general result of the large optimum pin spacings in our APC wires. This thesis research was the result of a collaboration between Yale University and IGC-Advanced Superconductors (Waterbury, CT).

  7. Pin and roller attachment system for ceramic blades

    DOEpatents

    Shaffer, James E.

    1995-01-01

    In a turbine, a plurality of blades are attached to a turbine wheel by way of a plurality of joints which form a rolling contact between the blades and the turbine wheel. Each joint includes a pin and a pair of rollers to provide rolling contact between the pin and an adjacent pair of blades. Because of this rolling contact, high stress scuffing between the blades and the turbine wheel reduced, thereby inhibiting catastrophic failure of the blade joints.

  8. Pin and roller attachment system for ceramic blades

    DOEpatents

    Shaffer, J.E.

    1995-07-25

    In a turbine, a plurality of blades are attached to a turbine wheel by way of a plurality of joints which form a rolling contact between the blades and the turbine wheel. Each joint includes a pin and a pair of rollers to provide rolling contact between the pin and an adjacent pair of blades. Because of this rolling contact, high stress scuffing between the blades and the turbine wheel reduced, thereby inhibiting catastrophic failure of the blade joints. 3 figs.

  9. Auto-adjustable pin tool for friction stir welding

    NASA Technical Reports Server (NTRS)

    Ding, R. Jeffrey (Inventor); Oelgoetz, Peter A. (Inventor)

    1999-01-01

    An auto-adjusting pin tool for friction stir welding is presented wherein the pin tool automatically adjusts for welding materials of varying thicknesses, and the pin can be incrementally withdrawn from the workpieces thus eliminating any crater or keyhole in the weld. The inventive apparatus is comprised of a welding head housing a motor connected to a controller instrument package and an arbor supported by bearings. The arbor forms an interior cylinder and is encircled by a stationary slip ring though which are ported hydraulic passageways into the interior cylinder of the arbor such that a piston housed therein may be moved axially. Coupled to the piston is a pin tool which is treaded on its lower end and which is moveably seated in, and extending through, a shoulder housing having concave lower face. When welding, the rotating treaded end of the pin enters and stirs the workpieces while the lower face of the shoulder housing compacts the workpieces. As the welding head traverses the shoulder housing the controller senses any rising pressure on the lower face of the shoulder housing and withdraws the arbor to keep the pressure constant. At the same time, the piston moves towards the workpieces thus extending the pin further from the shoulder. This keeps the pin at a proper depth in the workpieces regardless of their thicknesses. As the weld terminates this same operation can be used to incrementally withdraw the pin during the final part of the traverse, thus eliminating any keyhole or crater that would otherwise be created.

  10. Electrically controlled pinning of Dzyaloshinskii-Moriya domain walls

    NASA Astrophysics Data System (ADS)

    Sato, Koji; Tretiakov, Oleg A.

    2016-03-01

    We propose a method to all-electrically control a domain-wall position in a ferromagnetic nanowire with Dzyaloshinskii-Moriya interaction. The strength of this interaction can be controlled by an external electric field, which in turn allows a fine tuning of the pinning potential of a spin-spiral domain wall. It allows to create more mobile pinning sites and can also be advantageous for ultra-low power electronics.

  11. IMp: The customizable LEGO(®) Pinned Insect Manipulator.

    PubMed

    Dupont, Steen; Price, Benjamin; Blagoderov, Vladimir

    2015-01-01

    We present a pinned insect manipulator (IMp) constructed of LEGO® building bricks with two axes of movement and two axes of rotation. In addition we present three variants of the IMp to emphasise the modular design, which facilitates resizing to meet the full range of pinned insect specimens, is fully customizable, collapsible, affordable and does not require specialist tools or knowledge to assemble. PMID:25685035

  12. Pinned vortex hopping in a neutron star crust

    NASA Astrophysics Data System (ADS)

    Haskell, B.; Melatos, A.

    2016-06-01

    The motion of superfluid vortices in a neutron star crust is at the heart of most theories of pulsar glitches. Pinning of vortices to ions can decouple the superfluid from the crust and create a reservoir of angular momentum. Sudden large scale unpinning can lead to an observable glitch. In this paper we investigate the scattering of a free vortex off a pinning potential and calculate its mean free path, in order to assess whether unpinned vortices can skip multiple pinning sites and come close enough to their neighbours to trigger avalanches, or whether they simply hop from one pinning site to its neighbour, giving rise to a more gradual creep. We find that there is a significant range of parameter space in which avalanches can be triggered, thus supporting the hypothesis that they may lie at the origin of pulsar glitches. For realistic values of the pinning force and superfluid drag parameters we find that avalanches are more likely in the higher density regions of the crust where pinning is stronger. Physical differences in stellar parameters, such as mass and temperature, may lead to a switch between creep-like motion and avalanches, explaining the different characteristics of glitching pulsars.

  13. Numerical modeling of pin-fin micro heat exchangers

    NASA Astrophysics Data System (ADS)

    Galvis, E.; Jubran, B. A.; Behdinan, F. Xi. K.; Fawaz, Z.

    2008-04-01

    A micro heat exchanger (MHE) can effectively control the temperature of surfaces in high heat flux applications. In this study, several turbulence models are analyzed using a 3D finite element model of a MHE. The MHE consists of a narrow planar flow passage between flat parallel plates with small cylindrical pin fins spanning these walls. The pin fin array geometry investigated is staggered, with pin diameters of 0.5, 5.1 and 8.5 mm, height to diameter ratio of 1.0 and streamwise (longitudinal) and spanwise (transverse) to diameter ratios of 1.5 and 2.5, respectively. Pressure loss and heat transfer simulated results for 4,000 ≤ Re ≤ 50,000 are reported and compared with previously published numerical and experimental results. It was found that the flat micro pin fin overall thermal performance always exceeds that of the parallel plate counterpart (smooth channel) by a factor of as much as 2.2 for the 8.5 mm diameter pins, and by 4 for the 0.5 mm diameter pins in the investigated Reynolds number range. Further, among the six turbulence models investigated, the RNG model tends to be the best model to predict both the Nusselt number and the friction factor and capture the main feature of the flow field in MHE.

  14. A complication following ACL reconstruction using bioabsorbable cross-pins.

    PubMed

    Vecchini, Eugenio; Micheloni, Gian Mario; Corbo, Valentina Rita; Perusi, Francesco; Dib, Giovanni; Magnan, Bruno

    2016-01-01

    This is a case of a proximal pin migration after ACL reconstruction in medial soft tissue with pain, inflammatory reaction and functional reduction. 33-year-old male presented at our clinic with a complete ACL rupture. Reconstruction with autogenous gracilis and semitendinosus hamstring tendons was performed and graft fixed in the femoral canal with two PLLA bioabsorbable pins (RIGIDFIX® Cross Pin System). Two months postoperatively the patient presented swelling and pain on the medial side of the knee, full range of motion and negative results at the Lachman and Pivot shift tests. MRI examination showed the superior femoral tunnel crossing both the lateral and medial cortex lodging the pin in the knee's medial soft tissue corresponding to the swelling area reported by the patient. The tendon graft was properly positioned. After surgical removal of the pin through a small skin incision, the pain and swelling promptly subsided allowing the patient return to normal activities in few weeks without any pain. In our opinion the painful swelling of the knee was due to a displacement of the pin that had been accidentally lodged in the soft tissues instead of the bone causing a foreign-body reaction resulting in granuloma formation with local inflammation. This dislodgement could have been due to an inappropriately long femoral tunnel. PMID:27104331

  15. Pinned vortex hopping in a neutron star crust

    NASA Astrophysics Data System (ADS)

    Haskell, B.; Melatos, A.

    2016-09-01

    The motion of superfluid vortices in a neutron star crust is at the heart of most theories of pulsar glitches. Pinning of vortices to ions can decouple the superfluid from the crust and create a reservoir of angular momentum. Sudden large-scale unpinning can lead to an observable glitch. In this paper, we investigate the scattering of a free vortex off a pinning potential and calculate its mean free path, in order to assess whether unpinned vortices can skip multiple pinning sites and come close enough to their neighbours to trigger avalanches, or whether they simply hop from one pinning site to its neighbour, giving rise to a more gradual creep. We find that there is a significant range of parameter space in which avalanches can be triggered, thus supporting the hypothesis that they may lie at the origin of pulsar glitches. For realistic values of the pinning force and superfluid drag parameters, we find that avalanches are more likely in the higher density regions of the crust where pinning is stronger. Physical differences in stellar parameters, such as mass and temperature, may lead to a switch between creep-like motion and avalanches, explaining the different characteristics of glitching pulsars.

  16. Dipentamethylene thiuram monosulfide is a novel inhibitor of Pin1

    SciTech Connect

    Tatara, Yota; Lin, Yi-Chin; Bamba, Yoshimasa; Mori, Tadashi; Uchida, Takafumi

    2009-07-03

    Pin1 is involved in eukaryotic cell proliferation by changing the structure and function of phosphorylated proteins. PiB, the Pin1 specific inhibitor, blocks cancer cell proliferation. However, low solubility of PiB in DMSO has limited studies of its effectiveness. We screened for additional Pin1 inhibitors and identified the DMSO-soluble compound dipentamethylene thiuram monosulfide (DTM) that inhibits Pin1 activity with an EC50 value of 4.1 {mu}M. Molecular modeling and enzyme kinetic analysis indicated that DTM competitively inhibits Pin1 activity, with a K{sub i} value of 0.05 {mu}M. The K{sub D} value of DTM with Pin1 was determined to be 0.06 {mu}M by SPR technology. Moreover, DTM specifically inhibited peptidyl-prolyl cis/trans isomerase activity in HeLa cells. FACS analysis showed that DTM induced G0 arrest of the HCT116 cells. Our results suggest that DTM has the potential to guide the development of novel antifungal and/or anticancer drugs.

  17. Self-pinning of a nanosuspension droplet: Molecular dynamics simulations

    NASA Astrophysics Data System (ADS)

    Shi, Baiou; Webb, Edmund B.

    2016-07-01

    Results are presented from molecular dynamics simulations of Pb(l) nanodroplets containing dispersed Cu nanoparticles (NPs) and spreading on solid surfaces. Three-dimensional simulations are employed throughout, but droplet spreading and pinning are reduced to two-dimensional processes by modeling cylindrical NPs in cylindrical droplets; NPs have radius RNP≅3 nm while droplets have initial R0≅42 nm . At low particle loading explored here, NPs in sufficient proximity to the initial solid-droplet interface are drawn into advancing contact lines; entrained NPs eventually bind with the underlying substrate. For relatively low advancing contact angle θadv, self-pinning on entrained NPs occurs; for higher θadv, depinning is observed. Self-pinning and depinning cases are compared and forces on NPs at the contact line are computed during a depinning event. Though significant flow in the droplet occurs in close proximity to the particle during depinning, resultant forces are relatively low. Instead, forces due to liquid atoms confined between the particles and substrate dominate the forces on NPs; that is, for the NP size studied here, forces are interface dominated. For pinning cases, a precursor wetting film advances ahead of the pinned contact line but at a significantly slower rate than for a pure droplet. This is because the precursor film is a bilayer of liquid atoms on the substrate surface but it is instead a monolayer film as it crosses over pinning particles; thus, mass delivery to the bilayer structure is impeded.

  18. Refixation of osteochondral fractures by ultrasound-activated, resorbable pins

    PubMed Central

    Neumann, H.; Schulz, A. P.; Gille, J.; Klinger, M.; Jürgens, C.; Reimers, N.; Kienast, B.

    2013-01-01

    Objectives Osteochondral injuries, if not treated adequately, often lead to severe osteoarthritis. Possible treatment options include refixation of the fragment or replacement therapies such as Pridie drilling, microfracture or osteochondral grafts, all of which have certain disadvantages. Only refixation of the fragment can produce a smooth and resilient joint surface. The aim of this study was the evaluation of an ultrasound-activated bioresorbable pin for the refixation of osteochondral fragments under physiological conditions. Methods In 16 Merino sheep, specific osteochondral fragments of the medial femoral condyle were produced and refixed with one of conventional bioresorbable pins, titanium screws or ultrasound-activated pins. Macro- and microscopic scoring was undertaken after three months. Results The healing ratio with ultrasound-activated pins was higher than with conventional pins. No negative heat effect on cartilage has been shown. Conclusion As the material is bioresorbable, no further surgery is required to remove the implant. MRI imaging is not compromised, as it is with implanted screws. The use of bioresorbable pins using ultrasound is a promising technology for the refixation of osteochondral fractures. PMID:23610699

  19. Mechanisms of Soldering Formation on Coated Core Pins

    NASA Astrophysics Data System (ADS)

    Song, Jie; Denouden, Tony; Han, Qingyou

    2012-02-01

    Die soldering is one of the major casting defects during the high-pressure die casting (HPDC) process, causing dimensional inaccuracy of the castings and increased downtimes of the HPDC machine. In this study, we analyzed actually failed core pins to determine the mechanism of soldering and its procedures. The results show that the soldering process starts from a local coating failure, involves a series of intermetallic phase formation from reactions between molten aluminum alloys and the H13 steel pin, and accelerates when an aluminum-rich, face-centered cubic (fcc) phase is formed between the intermetallic phases. It is the formation of the aluminum-rich fcc phase in the reaction region that joins the core pin with the casting, resulting in the sticking of the casting to the core pin. When undercuts are formed on the core pin, the ejection of castings from the die will lead to either a core pin failure or damages to the casting being ejected.

  20. Behaviour of irradiated PHWR fuel pins during high temperature heating

    NASA Astrophysics Data System (ADS)

    Viswanathan, U. K.; Unnikrishnan, K.; Mishra, Prerna; Banerjee, Suparna; Anantharaman, S.; Sah, D. N.

    2008-12-01

    Fuel pins removed from an irradiated pressurised heavy water reactor (PHWR) fuel bundle discharged after an extended burn up of 15,000 MWd/tU have been subjected to isothermal heating tests in temperature range 700-1300 °C inside hot-cells. The heating of the fuel pins was carried out using a specially designed remotely operable furnace, which allowed localized heating of about 100 mm length of the fuel pin at one end under flowing argon gas or in air atmosphere. Post-test examination performed in the hot-cells included visual examination, leak testing, dimension measurement and optical and scanning electron microscopy. Fuel pins having internal pressure of 2.1-2.7 MPa due to fission gas release underwent ballooning and micro cracking during heating for 10 min at 800 °C and 900 °C but not at 700 °C. Fuel pin heated at 1300 °C showed complete disruption of cladding in heating zone, due to the embrittlement of the cladding. The examination of fuel from the pin tested at 1300 °C showed presence of large number of bubbles; both intragranular as well as intergranular bubbles. Details of the experiments and the results are presented in this paper.

  1. Comparative stress effects of vented and nonvented self-threading retentive pins.

    PubMed

    Savoca, D E; Schmidt, J R

    1984-08-01

    Longitudinally vented self-threading pins do not demonstrate a significant improvement in the complete seating of the pins or a decrease of dentinal crazing. The link series technique does demonstrate a significant improvement in the complete seating of pins and in the prevention of misalignment of the pins with the channels. PMID:6590837

  2. Dynamical coupled-channels study of {pi}N {right arrow} {pi pi}N reactions.

    SciTech Connect

    Kamano, H.; Julia-Diaz, B.; Lee, T.-S. H.; Matsuyama, A.; Sato, T.; Physics; Jefferson Lab.; Univ. of Barcelona; Shizuoka Univ.; Osaka Univ.

    2009-02-24

    As a step toward performing a complete coupled-channels analysis of the world data of {pi}N,{gamma}*N {yields} {pi}N,{eta}N,{pi}{pi}N reactions, the {pi}N {yields} {pi}{pi}N reactions are investigated starting with the dynamical coupled-channels model developed in Phys. Rev. C 76, 065201 (2007). The channels included are {pi}N,{eta}N, and {pi}{pi}N which has {pi}{Delta},{rho}N, and {sigma}N resonant components. The nonresonant amplitudes are generated from solving a set of coupled-channels equations with the meson-baryon potentials defined by effective Lagrangians. The resonant amplitudes are generated from 16 bare excited nucleon (N*) states that are dressed by the nonresonant interactions as constrained by the unitarity condition. The data of total cross sections and {pi}N and {pi}{pi} invariant mass distributions of {pi} + p {yields} {pi} + {pi} + n, {pi} + {pi}0p and {pi} - p {yields} {pi} + {pi} - n, {pi} - {pi}0p,{pi}0{pi}0n reactions from threshold to the invariant mass W = 2 GeV can be described to a very large extent. We show the importance of the coupled-channels effects and the strong interference among the contributions from the {pi}{Delta},{sigma}N, and {rho}N channels. The large interference between the resonant and nonresonant amplitudes is also demonstrated. Possible future developments are discussed.

  3. Spatially periodic domain wall pinning potentials: Asymmetric pinning and dipolar biasing

    NASA Astrophysics Data System (ADS)

    Metaxas, P. J.; Zermatten, P.-J.; Novak, R. L.; Rohart, S.; Jamet, J.-P.; Weil, R.; Ferré, J.; Mougin, A.; Stamps, R. L.; Gaudin, G.; Baltz, V.; Rodmacq, B.

    2013-02-01

    Domain wall propagation has been measured in continuous, weakly disordered, quasi-two-dimensional, Ising-like magnetic layers that are subject to spatially periodic domain wall pinning potentials. The potentials are generated non-destructively using the stray magnetic field of ordered arrays of magnetically hard [Co/Pt]m nanoplatelets, which are patterned above and are physically separated from the continuous magnetic layer. The effect of the periodic pinning potentials on thermally activated domain wall creep dynamics is shown to be equivalent, at first approximation, to that of a uniform, effective retardation field, Hret, which acts against the applied field, H. We show that Hret depends not only on the array geometry but also on the relative orientation of H and the magnetization of the nanoplatelets. A result of the latter dependence is that wall-mediated hysteresis loops obtained for a set nanoplatelet magnetization exhibit many properties that are normally associated with ferromagnet/antiferromagnet exchange bias systems. These include a switchable bias, coercivity enhancement, and domain wall roughness that is dependent on the applied field polarity.

  4. Antimicrobial efficacy of external fixator pins coated with a lipid stabilized hydroxyapatite/chlorhexidine complex to prevent pin tract infection in a goat model.

    SciTech Connect

    Dejong, E. Schuyler; Deberardino, T. M.; Brooks, D. E.; Nelson, B. J.; Campbell, Allison A.; Bottoni, Craig R.; Pusateri, A. E.; Walton, R. S.; Guymon, C. H.; Mcmanus, Albert T.

    2001-06-01

    Background: Pin tract infection is a common complication of external fixation. An antiinfective external fixator pin might help to reduce the incidence of pin tract infection and improve pin fixation. Methods: Stainless steel and titanium external fixator pins, with and without a lipid stabilized hydroxyapatite/chlorhexidine coating, were evaluated in a goat model. Two pins contaminated with an identifiable Staphylococcus aureus strain were inserted into each tibia of 12 goats. The pin sites were examined daily. On day 14, the animals were killed, and the pin tips cultured. Insertion and extraction torques were measured. Results: Infection developed in 100% of uncoated pins, whereas coated pins demonstrated 4.2% infected, 12.5% colonized, and the remainder, 83.3%, had no growth (p < 0.01). Pin coating decreased the percent loss of fixation torque over uncoated pins (p = 0.04). Conclusion: These results demonstrate that the lipid stabilized hydroxyapatite/chlorhexidine coating was successful in decreasing infection and improving fixation of external fixator pins.

  5. Discovery of novel selenium derivatives as Pin1 inhibitors by high-throughput screening.

    PubMed

    Subedi, Amit; Shimizu, Takeshi; Ryo, Akihide; Sanada, Emiko; Watanabe, Nobumoto; Osada, Hiroyuki

    2016-06-01

    Peptidyl prolyl cis/trans isomerization by Pin1 regulates various oncogenic signals during cancer progression, and its inhibition through multiple approaches has established Pin1 as a therapeutic target. However, lack of simplified screening systems has limited the discovery of potent Pin1 inhibitors. We utilized phosphorylation-dependent binding of Pin1 to its specific substrate to develop a screening system for Pin1 inhibitors. Using this system, we screened a chemical library, and identified a novel selenium derivative as Pin1 inhibitor. Based on structure-activity guided chemical synthesis, we developed more potent Pin1 inhibitors that inhibited cancer cell proliferation. PMID:27120460

  6. Twitter Stream Archiver

    SciTech Connect

    Steed, Chad Allen

    2014-07-01

    The Twitter Archiver system allows a user to enter their Twitter developer account credentials (obtained separately from the Twitter developer website) and read from the freely available Twitter sample stream. The Twitter sample stream provides a random sample of the overall volume of tweets that are contributed by users to the system. The Twitter Archiver system consumes the stream and serializes the information to text files at some predefined interval. A separate utility reads the text files and creates a searchable index using the open source Apache Lucene text indexing system.

  7. Twitter Stream Archiver

    Energy Science and Technology Software Center (ESTSC)

    2014-07-01

    The Twitter Archiver system allows a user to enter their Twitter developer account credentials (obtained separately from the Twitter developer website) and read from the freely available Twitter sample stream. The Twitter sample stream provides a random sample of the overall volume of tweets that are contributed by users to the system. The Twitter Archiver system consumes the stream and serializes the information to text files at some predefined interval. A separate utility reads themore » text files and creates a searchable index using the open source Apache Lucene text indexing system.« less

  8. Stochastic ice stream dynamics.

    PubMed

    Mantelli, Elisa; Bertagni, Matteo Bernard; Ridolfi, Luca

    2016-08-01

    Ice streams are narrow corridors of fast-flowing ice that constitute the arterial drainage network of ice sheets. Therefore, changes in ice stream flow are key to understanding paleoclimate, sea level changes, and rapid disintegration of ice sheets during deglaciation. The dynamics of ice flow are tightly coupled to the climate system through atmospheric temperature and snow recharge, which are known exhibit stochastic variability. Here we focus on the interplay between stochastic climate forcing and ice stream temporal dynamics. Our work demonstrates that realistic climate fluctuations are able to (i) induce the coexistence of dynamic behaviors that would be incompatible in a purely deterministic system and (ii) drive ice stream flow away from the regime expected in a steady climate. We conclude that environmental noise appears to be crucial to interpreting the past behavior of ice sheets, as well as to predicting their future evolution. PMID:27457960

  9. Stochastic ice stream dynamics

    NASA Astrophysics Data System (ADS)

    Mantelli, Elisa; Bertagni, Matteo Bernard; Ridolfi, Luca

    2016-08-01

    Ice streams are narrow corridors of fast-flowing ice that constitute the arterial drainage network of ice sheets. Therefore, changes in ice stream flow are key to understanding paleoclimate, sea level changes, and rapid disintegration of ice sheets during deglaciation. The dynamics of ice flow are tightly coupled to the climate system through atmospheric temperature and snow recharge, which are known exhibit stochastic variability. Here we focus on the interplay between stochastic climate forcing and ice stream temporal dynamics. Our work demonstrates that realistic climate fluctuations are able to (i) induce the coexistence of dynamic behaviors that would be incompatible in a purely deterministic system and (ii) drive ice stream flow away from the regime expected in a steady climate. We conclude that environmental noise appears to be crucial to interpreting the past behavior of ice sheets, as well as to predicting their future evolution.

  10. Stream-gaging cableways

    USGS Publications Warehouse

    Wagner, C. Russell

    1995-01-01

    This manual provides a series of standard designs for stream-gaging cableways used by the U.S. Geological Survey (USGS). It provides helpful information on construction, inspection, and maintenance of cableways.