A momentum source model for wire-wrapped rod bundles—Concept, validation, and application
Hu, Rui; Fanning, Thomas H.
2013-06-19
Large uncertainties still exist in the treatment of wire-spacers and drag models for momentum transfer in current lumped parameter models. Here, to improve the hydraulic modeling of wire-wrap spacers in a rod bundle, a three-dimensional momentum source model (MSM) has been developed to model the anisotropic flow without the need to resolve the geometric details of the wire-wraps. The MSM is examined for 7-pin and 37-pin bundles steady-state simulations using the commercial CFD code STAR-CCM+. The calculated steady-state inter-subchannel cross flow velocities match very well in comparisons between bare bundles with the MSM applied and the wire-wrapped bundles with explicitmore » geometry. The validity of the model is further verified by mesh and parameter sensitivity studies. Furthermore, the MSM is applied to a 61-pin EBR-II experimental subassembly for both steady state and PLOF transient simulations. Reasonably accurate predictions of temperature, pressure, and fluid flow velocities have been achieved using the MSM for both steady-state and transient conditions. Significant computing resources are saved with the MSM since it can be used on a much coarser computational mesh.« less
Kaplan, Samuel; Chertock, Alan J.; Punches, James R.
1977-01-01
A method for spacing fast reactor fuel rods using a wire wrapper improved by orienting the wire-wrapped fuel rods in a unique manner which introduces desirable performance characteristics not attainable by previous wire-wrapped designs. Use of this method in a liquid metal fast breeder reactor results in: (a) improved mechanical performance, (b) improved rod-to-rod contact, (c) reduced steel volume, and (d) improved thermal-hydraulic performance. The method produces a "locked wrap" design which tends to lock the rods together at each of the wire cluster locations.
Distributed temperature sensing inside a 19-rod bundle
Lomperski, S.; Bremer, N.; Gerardi, C.
2017-05-23
The temperature field within a model of a sodium-cooled fast reactor fuel rod bundle was measured using Ø155 μm fiber optic distributed temperature sensors (DTS). The bundle consists of 19 electrically-heated rods Ø6.3 mm and 865 mm long. Working fluids were argon and air at atmospheric pressure and Reynolds numbers up to 300. A 20 m-long DTS was threaded through Ø1 mm capillaries wound around rods as wire-wraps. The sensor generated 173 measurements along each rod at 5 mm resolution for a total of 3300 data locations. A second DTS, 58 m long, was suspended between rods to provide 9300more » fluid temperature measurements at 20 mm resolution. Such data density makes it possible to construct 3D maps of the temperature field that are beyond the reach of traditional sensors such as thermocouples. This is illustrated through a series of steady-state and transient tests. As a result, the work demonstrates the feasibility of mapping temperature within the close confines of a rod bundle at resolutions suitable for validation of computational fluid dynamics codes.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dearing, J F; Rose, S D; Nelson, W R
The predicted computational results of two well-known sub-channel analysis codes, COBRA-III-C and SABRE-I (wire wrap version), have been evaluated by comparison with steady state temperature data from the THORS Facility at ORNL. Both codes give good predictions of transverse and axial temperatures when compared with wire wrap thermocouple data. The crossflow velocity profiles predicted by these codes are similar which is encouraging since the wire wrap models are based on different assumptions.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dearing, J F; Nelson, W R; Rose, S D
Computational thermal-hydraulic models of a 19-pin, electrically heated, wire-wrap liquid-metal fast breeder reactor test bundle were developed using two well-known subchannel analysis codes, COBRA III-C and SABRE-1 (wire-wrap version). These two codes use similar subchannel control volumes for the finite difference conservation equations but vary markedly in solution strategy and modeling capability. In particular, the empirical wire-wrap-forced diversion crossflow models are different. Surprisingly, however, crossflow velocity predictions of the two codes are very similar. Both codes show generally good agreement with experimental temperature data from a test in which a large radial temperature gradient was imposed. Differences between data andmore » code results are probably caused by experimental pin bowing, which is presently the limiting factor in validating coded empirical models.« less
Thermal degradation products from PVC film in food-wrapping operations.
Boettner, E A; Ball, G L
1980-07-01
Thermal degradation products of polyvinyl chloride (PVC) food-wrap films were studied under simulated supermarket conditons using a commercial wrapping machine with either a hot wire or a cool rod cutting device. A sampling hood was constructed around the wire/rod to confine and allow collection of thermal degradation products produced. Compounds analyzed and normal concentration ranges found included hydrogen chloride (1-10 micrograms per cut), plasticizer (1-50 micrograms per cut), benzene and toluene (each < 5-20 ng per cut), acrolein (25-150 ng per cut), and carbon monoxide (2-4 micrograms per cut) using the hot wire. Room air samples, collected during hot-wire cutting without the sampling hood, had < 0.25 ppm hydrogen chloride. Using the cool-rod cutting device hydrogen chloride, benzene, and toluene were not detected. Plasticizer was detected (25-86 micrograms per cut) using the cool rod.
Coolant mixing in LMFBR rod bundles and outlet plenum mixing transients. Final report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Todreas, N.E.; Cheng, S.K.; Basehore, K.
1984-08-01
This project principally undertook the investigation of the thermal hydraulic performance of wire wrapped fuel bundles of LMFBR configuration. Results obtained included phenomenological models for friction factors, flow split and mixing characteristics; correlations for predicting these characteristics suitable for insertion in design codes; numerical codes for analyzing bundle behavior both of the lumped subchannel and distributed parameter categories and experimental techniques for pressure velocity, flow split, salt conductivity and temperature measurement in water cooled mockups of bundles and subchannels. Flow regimes investigated included laminar, transition and turbulent flow under forced convection and mixed convection conditions. Forced convections conditions were emphasized.more » Continuing efforts are underway at MIT to complete the investigation of the mixed convection regime initiated here. A number of investigations on outlet plenum behavior were also made. The reports of these investigations are identified.« less
Evaluation of emissions from simulated commercial meat wrapping operations using PVC wrap.
Smith, T J; Cafarella, J J; Chelton, C; Crowley, S
1983-03-01
Meatwrapper's asthma is an elusive health problem with a suspected relationship to exposure to emissions from polyvinyl chloride (PVC) film cut with a hot wire. A study was conducted to determine how the type of wrap cutter (wire or rod) and its temperature affected the emissions from a simulated occupational wrapping process. The cutting temperatures covered the same range as was measured in Boston retail food stores. A commercial wrapping machine and samples of commercial PVC meat and produce wraps were used. Seventy five percent of the particulate from the hot wire was respirable, and the quantity of emissions was a strong function of the film tension and cutting technique. Particulate emissions did not increase steadily with increasing wire temperature, but plateaued or declined at high temperatures. Particulate emissions from the rod cutter were very low at low temperatures, but exceeded those of the wire at temperatures above 200 degrees C. The particulate was 100% dioctyl adipate (DOA, the plasticizer in the wrap) with wire temperatures below 200 degrees C, and was approximately 80% DOA for temperatures above this. Gaseous HCl was not detected in emissions from a hot wire operated below 150 degrees C, but HCl emissions increased rapidly to a plateau for temperatures above 200 degrees C. Approximately 20% of the HCl produced at temperatures above 200 degrees C was associated with the particulate, which appeared to act as a carrier and transport the HCl through water filled impingers. Field tests are needed to determine if particulate produced in the workplace may also behave as a carrier for HCl.
46 CFR 120.340 - Cable and wiring requirements.
Code of Federal Regulations, 2010 CFR
2010-10-01
... chafing and other damage. The use of plastic tie wraps must be limited to bundling or retention of... wires, rather than cables, are used in systems greater than 50 volts, the wire must be in conduit. (b... for the circuit in which they are used; (2) Be installed in a manner to avoid or reduce interference...
COMPARISON OF PRESSURE DROP PRODUCED BY SPIRAL WRAPS, COOKIE CUTTERS AND OTHER ROD BUNDLE SPACERS
DOE Office of Scientific and Technical Information (OSTI.GOV)
Noyes, R.C.
The problem of predicting pressure drop due to various fuel bundle spacers is considered in some detail. Three sets of experimental data are reviewed and presented in reduced form. These data are compared to several semitheoretical approaches to pressure drop prediction and a best method is selected to make the required predictions. The comparison between predictions for the ASCR spiral wrap spacer and cookie cutter spacer shows that both types of spacers produce about the same pressure drop. Spacer pressure drop is shown to be strongly dependent on spacer frontal area and pitch. (auth)
40 CFR 420.91 - Specialized definitions.
Code of Federal Regulations, 2010 CFR
2010-07-01
... wire, rods, and tubes in discrete batches or bundles. (f) The term continuous means those pickling operations which process steel products other than in discrete batches or bundles. (g) The term acid recovery...
NASA Astrophysics Data System (ADS)
Kim, Yang-Hee; Lee, Byong-Taek
2011-06-01
In this study, a novel artificial small bone consisting of ZrO2-biphasic calcium phosphate/polymethylmethacrylate-polycaprolactone-hydroxyapatite (ZrO2-BCP/PMMA-PCL-HAp) was fabricated using a combination of sponge replica and electrospinning methods. To mimic the cancellous bone, the ZrO2/BCP scaffold was composed of three layers, ZrO2, ZrO2/BCP and BCP, fabricated by the sponge replica method. The PMMA-PCL fibers loaded with HAp powder were wrapped around the ZrO2/BCP scaffold using the electrospinning process. To imitate the Haversian canal region of the bone, HAp-loaded PMMA-PCL fibers were wrapped around a steel wire of 0.3 mm diameter. As a result, the bundles of fiber wrapped around the wires imitated the osteon structure of the cortical bone. Finally, the ZrO2/BCP scaffold was surrounded by HAp-loaded PMMA-PCL composite bundles. After removal of the steel wires, the ZrO2/BCP scaffold and bundles of HAp-loaded PMMA-PCL formed an interconnected structure resembling the human bone. Its diameter, compressive strength and porosity were approximately 12 mm, 5 MPa and 70%, respectively, and the viability of MG-63 osteoblast-like cells was determined to be over 90% by the MTT (3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide) assay. This artificial bone shows excellent cytocompatibility and is a promising bone regeneration material.
Kim, Yang-Hee; Lee, Byong-Taek
2011-01-01
In this study, a novel artificial small bone consisting of ZrO2-biphasic calcium phosphate/polymethylmethacrylate-polycaprolactone-hydroxyapatite (ZrO2-BCP/PMMA-PCL-HAp) was fabricated using a combination of sponge replica and electrospinning methods. To mimic the cancellous bone, the ZrO2/BCP scaffold was composed of three layers, ZrO2, ZrO2/BCP and BCP, fabricated by the sponge replica method. The PMMA-PCL fibers loaded with HAp powder were wrapped around the ZrO2/BCP scaffold using the electrospinning process. To imitate the Haversian canal region of the bone, HAp-loaded PMMA-PCL fibers were wrapped around a steel wire of 0.3 mm diameter. As a result, the bundles of fiber wrapped around the wires imitated the osteon structure of the cortical bone. Finally, the ZrO2/BCP scaffold was surrounded by HAp-loaded PMMA-PCL composite bundles. After removal of the steel wires, the ZrO2/BCP scaffold and bundles of HAp-loaded PMMA-PCL formed an interconnected structure resembling the human bone. Its diameter, compressive strength and porosity were approximately 12 mm, 5 MPa and 70%, respectively, and the viability of MG-63 osteoblast-like cells was determined to be over 90% by the MTT (3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide) assay. This artificial bone shows excellent cytocompatibility and is a promising bone regeneration material. PMID:27877406
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mays, Brian; Jackson, R. Brian
2017-03-08
The project, Toward a Longer Life Core: Thermal Hydraulic CFD Simulations and Experimental Investigation of Deformed Fuel Assemblies, DOE Project code DE-NE0008321, was a verification and validation project for flow and heat transfer through wire wrapped simulated liquid metal fuel assemblies that included both experiments and computational fluid dynamics simulations of those experiments. This project was a two year collaboration between AREVA, TerraPower, Argonne National Laboratory and Texas A&M University. Experiments were performed by AREVA and Texas A&M University. Numerical simulations of these experiments were performed by TerraPower and Argonne National Lab. Project management was performed by AREVA Federal Services.more » The first of a kind project resulted in the production of both local point temperature measurements and local flow mixing experiment data paired with numerical simulation benchmarking of the experiments. The project experiments included the largest wire-wrapped pin assembly Mass Index of Refraction (MIR) experiment in the world, the first known wire-wrapped assembly experiment with deformed duct geometries and the largest numerical simulations ever produced for wire-wrapped bundles.« less
2011-03-01
Mile per hour ms Millisecond NEDU Navy Experimental Diving Unit PFD Personal flotation device PIW Person in the water PVC Polyvinyl chloride RDC...electrically resistive, yet conductive, clay. We then encapsulated the clay around a 1/2” diameter, 6-inch long copper rod, and then tightly wrapped it with...short length of 12 American Wire Gauge (AWG) stranded copper wire to the copper rod within each electrode. For each electrode pair, we joined
Electrically isolated, high melting point, metal wire arrays and method of making same
DOE Office of Scientific and Technical Information (OSTI.GOV)
Simpson, John T.; Cunningham, Joseph P.; D'Urso, Brian R.
2016-01-26
A method of making a wire array includes the step of providing a tube of a sealing material and having an interior surface, and positioning a wire in the tube, the wire having an exterior surface. The tube is heated to soften the tube, and the softened tube is drawn and collapsed by a mild vacuum to bring the interior surface of the tube into contact with the wire to create a coated wire. The coated wires are bundled. The bundled coated wires are heated under vacuum to fuse the tube material coating the wires and create a fused rodmore » with a wire array embedded therein. The fused rod is cut to form a wire array. A wire array is also disclosed.« less
Saran film is fire-retardant in oxygen atmosphere
NASA Technical Reports Server (NTRS)
Goodwin, J. T.; Herrera, W. R.
1968-01-01
Saran was tested for flammability as a wrapping on TFE-insulated electrical wire bundles in oxygen gas at pressures of 7.5 psia and 14.7 psia. It was found to be fire retardant or self-extinguishing in most instances.
A coolant flow simulation in fast reactor wire-wrapped assembly
NASA Astrophysics Data System (ADS)
Volkov, V. Yu.; Belova, O. V.; Krutikov, A. A.; Skibin, A. P.
2013-06-01
A CFD model of a 19-rod wire-wrapped fuel assembly is developed. The effect the size of computation mesh in the calculated region and the type of turbulence models have on the pressure drop between the inlet to and outlet from the calculated region is investigated. The possibility of shifting from low-Reynolds to high-Reynolds turbulence models is substantiated. Such a shift allows the mesh size in the calculated region to be reduced by approximately a factor of 18. The obtained results are in good agreement with the empirical dependences and international calculations.
40 CFR 420.111 - Specialized definitions.
Code of Federal Regulations, 2010 CFR
2010-07-01
... steel products such as coiled wire, rods, and tubes in discrete batches or bundles. (b) The term continuous means those alkaline cleaning operations which process steel products other than in discrete...
Reusable Hot-Wire Cable Cutter
NASA Technical Reports Server (NTRS)
Pauken, Michael T.; Steinkraus, Joel M.
2010-01-01
During the early development stage of balloon deployment systems for missions, nichrome wire cable cutters were often used in place of pyro-actuated cutters. Typically, a nichrome wire is wrapped around a bundle of polymer cables with a low melting point and connected to a relay-actuated electric circuit. The heat from the nichrome reduces the strength of the cable bundle, which quickly breaks under a mechanical load and can thus be used as a release mechanism for a deployment system. However, the use of hand-made heated nichrome wire for cutters is not very reliable. Often, the wrapped nichrome wire does not cut through the cable because it either pulls away from its power source or does not stay in contact with the cable being cut. Because nichrome is not readily soldered to copper wire, unreliable mechanical crimps are often made to connect the nichrome to an electric circuit. A self-contained device that is reusable and reliable was developed to sever cables for device release or deployment. The nichrome wire in this new device is housed within an enclosure to prevent it from being damaged by handling. The electric power leads are internally connected within the unit to the nichrome wire using a screw terminal connection. A bayonet plug, a quick and secure method of connecting the cutter to the power source, is used to connect the cutter to the power leads similar to those used in pyro-cutter devices. A small ceramic tube [0.25-in. wide 0.5-in. long (.6.4-mm wide 13-mm long)] houses a spiraled nichrome wire that is heated when a cable release action is required. The wire is formed into a spiral coil by wrapping it around a mandrel. It is then laid inside the ceramic tube so that it fits closely to the inner surface of the tube. The ceramic tube provides some thermal and electrical insulation so that most of the heat generated by the wire is directed toward the cable bundle in the center of the spiral. The ceramic tube is cemented into an aluminum block, which holds it in position. The leads of the nichrome wire are attached to screw terminals that connect them to power leads. A bayonet plug mounted at the bottom of the rectangular block connects the power leads to a relay circuit. A thin aluminum shell encloses the entire structure, leaving access points to attach to the bayonet plug and to feed a cable into the cylinder. The access holes for the deployment cable are a smaller diameter than the nichrome coil to prevent the cable from coming in direct contact with the nichrome when loaded. It uses the same general method of severing a cable with a heated wire as was used previously, but implements it in such a way that it is more reliable and less prone to failure. It creates a mechanism to create repeatability that was nonexistent in the previous method.
Far infrared polarizing grids for use at cryogenic temperatures
NASA Technical Reports Server (NTRS)
Novak, Giles; Sundwall, Jeffrey L.; Pernic, Robert J.
1989-01-01
A technique is proposed for the construction of free-standing wire grids for use as far-IR polarizers. The method involves wrapping a strand of wire around a single cylinder rather than around a pair of parallel rods, thus simplifying the problem of maintaining constant wire tension. The cylinder is composed of three separate pieces which are disassembled at a later stage in the grid-making process. Grids have been constructed using 8-micron-diameter stainless steel wire and a grid spacing of 25 microns. The grids are shown to be reliable under repeated cycling between room temperature and 1.5 K.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Popov, Emilian L.; Pointer, William David
This work assesses the influence of assumptions made when generating a mesh of a wire-wrappedgeometry. The contact region between a wire and its adjacent pin is commonly modeled by eitherembedding the wire to the adjacent pin or trimming the wire so that a gap separates the wire from itsadjacent pin. These models are referred to as close-gap and open-gap approaches herein and are applied totwo geometries. The first geometry consists of a single pin wire-wrapped subchannel. A polyhedral meshand a hexahedral mesh are generated. The second and third geometry are a 7-pin and a 19-pinwire-wrapped bundles meshed with polyhedral elementsmore » only. Pressure drops are obtained with theSTAR-CCM+computational fluid dynamic package. Sensitivity analyses of the mesh density, the meshtype, and the turbulent models are performed. Numerical results show that the best match to theexperimental data and to the Cheng-Todreas correlation is obtained with the combination of a hexahedralmesh, the shear stress transport (SST) turbulent model, and the open-gap approach. In the case of the 7-pingeometry, the best results are obtained with the open-gap approach and the SST turbulent model. The19-pin geometry yields contradictory results to the 7-pin geometry results, and thus will require furtherinvestigations.« less
Noise Radiation from Single and Multiple Rod Configurations
NASA Technical Reports Server (NTRS)
Hutcheson, Florence V.; Brooks, Thomas F.
2006-01-01
Acoustic measurements were performed on single and multiple rod configurations to study the effect of Reynolds number, surface roughness, freestream turbulence, proximity and wake interference on the radiated noise. The Reynolds number ranged from 3.8 x 10(exp 3) to 10(exp 5). Directivity measurements were performed to determine how well the dipole assumption for the radiation of vortex shedding noise holds for the different model configurations tested. The dependence of the peak Sound Pressure Level on velocity was also examined. Several concepts for the reduction of the noise radiating from cylindrical rods were tested. It was shown that wire wraps and collar distributions could be used to significantly reduce the noise radiating from rods in tandem configurations.
40 CFR 420.111 - Specialized definitions.
Code of Federal Regulations, 2011 CFR
2011-07-01
... steel products such as coiled wire, rods, and tubes in discrete batches or bundles. (b) The term continuous means those alkaline cleaning operations which process steel products other than in discrete... AND STANDARDS IRON AND STEEL MANUFACTURING POINT SOURCE CATEGORY Alkaline Cleaning Subcategory § 420...
Multi-pin chemiresistors for microchemical sensors
Ho, Clifford K [Albuquerque, NM
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.
Cook, W A
1980-07-01
An industrial hygiene evaluation is presented concerning experimental data included in the preceding paper on thermal degradation products from hot-wire and "cool"-rod cutting of PVC film but, in this paper, limited to film used in meat-wrapping operations. Room air concentrations of less than 0.2 ppm HCl and less than 0.05 ppm benzene can be maintained by a number of factors, including minimal dilution ventilation. Estimates of room air concentrations of degradation products are presented using average values of amounts produced per cut. The relation of these concentrations to TLV's is given, together with methods of suggesting TLV's for substances not listed by ACGIH or OSHA. Room air concentrations for the 12 degradation products for which TLV's are assigned, based on average values per cut, were no greater than 0.3% of accepted limits. Room air concentrations of DOA are not determinable from available data but present information does not indicate that exposure to DOA causes airway hyperreactivity. The cool rod, rather than the hot wire, is recommended as good industrial hygiene practice, producing no apparent PVC degradation products, even though similar amounts of DOA are volatilized.
Structural Integrity Testing Method for PRSEUS Rod-Wrap Stringer Design
NASA Technical Reports Server (NTRS)
Wang, John T.; Grenoble, Ray W.; Pickell, Robert D.
2012-01-01
NASA Langley Research Center and The Boeing Company are developing an innovative composite structural concept, called PRSEUS, for the flat center section of a future environmentally friendly hybrid wing body (HWB) aircraft. The PRSEUS (Pultruded Rod Stitched Efficient Unitized Structure) concept uses dry textile preforms for the skins, frames, and stiffener webs. The highly loaded stiffeners are made from precured unidirectional carbon/epoxy rods and dry fiber preforms. The rods are wrapped with the dry fiber preforms and a resin infusion process is used to form the rod-wrap stiffeners. The structural integrity of the rod-wrap interface is critical for maintaining the panel s high strength and bending rigidity. No standard testing method exists for testing the strength of the rod-wrap bondline. Recently, Boeing proposed a rod push-out testing method and conducted some preliminary tests using this method. This paper details an analytical study of the rod-wrap bondline. The rod-wrap interface is modeled as a cohesive zone for studying the initiation and growth of interfacial debonding during push-out testing. Based on the correlations of analysis results and Boeing s test data, the adequacy of the rod-wrap testing method is evaluated, and potential approaches for improvement of the test method are proposed.
Effects of number and configuration of flagella on motility of Helicobacter species.
NASA Astrophysics Data System (ADS)
Constantino, Maira A.; Sharba, Sinan; Shen, Zeli; Fox, James G.; Haesebrouck, Freddy; Linden, Sara; Bansil, Rama
Helicobacters are ulcer-causing bacteria that colonize the viscoelastic gastric mucus layer of mammals. Previous studies have shown that motility and colonization are affected by helical body shape, number and configuration of flagella. In a recent study, using fast time-resolution and high-magnification 2-D phase-contrast microscopy to image individual helical and rod-shaped H. pylori we measured the rotation rate of the cell body and flagella and found that helical shape produces less than 15% changes in swimming speeds as compared to the rod-shaped cell. Motility of H. pylori was strongly influenced by its multiple unipolar flagella. Here we compare rotational and translational speeds of H. cetorum and H. suis which have bipolar flagella, with H. cetorum having single bipolar flagella and H. suis having multiple flagella. Preliminary results show that H. suis bacteria swim slower but rotate at the same rate as H. pylori and present two swimming modes. It can swim as a pusher, with one active rotating bundle and one inactive bundle, wrapped around the body or with both bundles active. Similar work on H. cetorum is ongoing and will also be presented. NSF PHY 1410798.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dearing, J.F.
The Subchannel Analysis of Blockages in Reactor Elements (SABRE) computer code, developed by the United Kingdom Atomic Energy Authority, is currently the only practical tool available for performing detailed analyses of velocity and temperature fields in the recirculating flow regions downstream of blockages in liquid-metal fast breeder reactor (LMFBR) pin bundles. SABRE is a subchannel analysis code; that is, it accurately represents the complex geometry of nuclear fuel pins arranged on a triangular lattice. The results of SABRE computational models are compared here with temperature data from two out-of-pile 19-pin test bundles from the Thermal-Hydraulic Out-of-Reactor Safety (THORS) Facility atmore » Oak Ridge National Laboratory. One of these bundles has a small central flow blockage (bundle 3A), while the other has a large edge blockage (bundle 5A). Values that give best agreement with experiment for the empirical thermal mixing correlation factor, FMIX, in SABRE are suggested. These values of FMIX are Reynolds-number dependent, however, indicating that the coded turbulent mixing correlation is not appropriate for wire-wrap pin bundles.« less
Magnet-wire wrapping tool for integrated circuits
NASA Technical Reports Server (NTRS)
Takahashi, T. H.
1972-01-01
Wire-dispensing tool which resembles mechanical pencil is used to wrap magnet wire around integrated circuit terminals uniformly and securely without damaging insulative coating on wire. Tool is hand-held and easily manipulated to execute wire wrapping movements.
Detection of low level benzene exposure in supermarket wrappers by urinary muconic acid.
E S Johnson S Halabi G Netto G Lucier W Bechtold R Henderson
1999-01-01
Women who use the 'hot wire' and 'cool rod' machines to wrap meat in supermarkets are potentially exposed to low levels of benzene and polycyclic aromatic hydrocarbons present in fumes emitted during the thermal decomposition of the plastic used to wrap meat. In order to evaluate whether the benzene metabolite trans, trans-muconic acid (MA) can be used to monitor these low levels, we collected urine samples from supermarket workers, and assayed the urine for MA. Geometric mean after-shift MA levels were highest for subjects who used the 'hot wire' machine, i.e. > 300 ng mg-1 creatinine (Cr). The corresponding levels for subjects who used the 'cool rod' machine were similar to those for subjects who did not use either type of machine, and were much lower. These results indicate that urinary muconic acid has some potential for use in monitoring benzene exposures of less than 1 part per million (ppm). The study detected very high background MA levels (exceeding 2000 ng mg-1 Cr) in some subjects, suggesting that individuals in the general population without occupational exposure to benzene may have urinary MA levels equivalent to exposure to up to 2 ppm benzene in ambient air. However, since non-benzene sources of the metabolite cannot be completely ruled out as partially responsible for these high levels, the public health significance of this finding is not known at the moment.
Li, Yongliang; Jiang, Tao; Lin, Shaoliang; Lin, Jiaping; Cai, Chunhua; Zhu, Xingyu
2015-01-01
Self-assembly behavior of a mixture system containing rod-coil block copolymers and rigid homopolymers was investigated by using Brownian dynamics simulations. The morphologies of formed hierarchical self-assemblies were found to be dependent on the Lennard-Jones (LJ) interaction εRR between rod blocks, lengths of rod and coil blocks in copolymer, and mixture ratio of block copolymers to homopolymers. As the εRR value decreases, the self-assembled structures of mixtures are transformed from an abacus-like structure to a helical structure, to a plain fiber, and finally are broken into unimers. The order parameter of rod blocks was calculated to confirm the structure transition. Through varying the length of rod and coil blocks, the regions of thermodynamic stability of abacus, helix, plain fiber, and unimers were mapped. Moreover, it was discovered that two levels of rod block ordering exist in the helices. The block copolymers are helically wrapped on the homopolymer bundles to form helical string, while the rod blocks are twistingly packed inside the string. In addition, the simulation results are in good agreement with experimental observations. The present work reveals the mechanism behind the formation of helical (experimentally super-helical) structures and may provide useful information for design and preparation of the complex structures. PMID:25965726
Respiratory effects of work in retail food stores. III. Pulmonary function findings.
Wegman, D H; Eisen, E A; Smith, T J; Greaves, I A; Fine, L J
1987-06-01
Findings are reported from a prospective morbidity study which examined the effects on pulmonary function associated with the particulate and gaseous air contaminants to which retail food store workers are exposed. A total of 685 supermarket employees (including meat wrappers, meat cutters and store clerks) performed standard ventilatory function tests [forced expiratory volume in 1 s (FEV1.0) and forced vital capacity (FVC)] during a base-line survey. Those available four years later (305) were resurveyed in a similar manner. A suggestive chronic effect on pulmonary function was shown in those with high cumulative exposures and allergic history. Among those workers who had continuous exposure to air contaminants in settings with "hot-wire" plastic wrap film cutters the annual rates of change in FEV1.0 and FVC were twice as great as the changes found among comparable workers who were not exposed to fumes from wrapping film. Those who switched from the "hot-wire" to the "cool-rod" cutters during the course of the follow-up had intermediate rates of change in lung function.
Assessment of SFR Wire Wrap Simulation Uncertainties
DOE Office of Scientific and Technical Information (OSTI.GOV)
Delchini, Marc-Olivier G.; Popov, Emilian L.; Pointer, William David
Predictive modeling and simulation of nuclear reactor performance and fuel are challenging due to the large number of coupled physical phenomena that must be addressed. Models that will be used for design or operational decisions must be analyzed for uncertainty to ascertain impacts to safety or performance. Rigorous, structured uncertainty analyses are performed by characterizing the model’s input uncertainties and then propagating the uncertainties through the model to estimate output uncertainty. This project is part of the ongoing effort to assess modeling uncertainty in Nek5000 simulations of flow configurations relevant to the advanced reactor applications of the Nuclear Energy Advancedmore » Modeling and Simulation (NEAMS) program. Three geometries are under investigation in these preliminary assessments: a 3-D pipe, a 3-D 7-pin bundle, and a single pin from the Thermal-Hydraulic Out-of-Reactor Safety (THORS) facility. Initial efforts have focused on gaining an understanding of Nek5000 modeling options and integrating Nek5000 with Dakota. These tasks are being accomplished by demonstrating the use of Dakota to assess parametric uncertainties in a simple pipe flow problem. This problem is used to optimize performance of the uncertainty quantification strategy and to estimate computational requirements for assessments of complex geometries. A sensitivity analysis to three turbulent models was conducted for a turbulent flow in a single wire wrapped pin (THOR) geometry. Section 2 briefly describes the software tools used in this study and provides appropriate references. Section 3 presents the coupling interface between Dakota and a computational fluid dynamic (CFD) code (Nek5000 or STARCCM+), with details on the workflow, the scripts used for setting up the run, and the scripts used for post-processing the output files. In Section 4, the meshing methods used to generate the THORS and 7-pin bundle meshes are explained. Sections 5, 6 and 7 present numerical results for the 3-D pipe, the single pin THORS mesh, and the 7-pin bundle mesh, respectively.« less
Heat Transfer Analysis in Wire Bundles for Aerospace Vehicles
NASA Technical Reports Server (NTRS)
Rickman, S. L.; Iamello, C. J.
2016-01-01
Design of wiring for aerospace vehicles relies on an understanding of "ampacity" which refers to the current carrying capacity of wires, either, individually or in wire bundles. Designers rely on standards to derate allowable current flow to prevent exceedance of wire temperature limits due to resistive heat dissipation within the wires or wire bundles. These standards often add considerable margin and are based on empirical data. Commercial providers are taking an aggressive approach to wire sizing which challenges the conventional wisdom of the established standards. Thermal modelling of wire bundles may offer significant mass reduction in a system if the technique can be generalized to produce reliable temperature predictions for arbitrary bundle configurations. Thermal analysis has been applied to the problem of wire bundles wherein any or all of the wires within the bundle may carry current. Wire bundles present analytical challenges because the heat transfer path from conductors internal to the bundle is tortuous, relying on internal radiation and thermal interface conductance to move the heat from within the bundle to the external jacket where it can be carried away by convective and radiative heat transfer. The problem is further complicated by the dependence of wire electrical resistivity on temperature. Reduced heat transfer out of the bundle leads to higher conductor temperatures and, hence, increased resistive heat dissipation. Development of a generalized wire bundle thermal model is presented and compared with test data. The steady state heat balance for a single wire is derived and extended to the bundle configuration. The generalized model includes the effects of temperature varying resistance, internal radiation and thermal interface conductance, external radiation and temperature varying convective relief from the free surface. The sensitivity of the response to uncertainties in key model parameters is explored using Monte Carlo analysis.
Fabrication of multifilamentary Nb/sub 3/(Al,Ge) wires through a modified jelly roll process
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tachikawa, K.; Kamisada, Y.; Suzuki, E.
Recently, development of Nb/sub 3/Al multifilamentary wires has gained much interests since high-field performance superior to that of Nb/sub 3/Sn can be expected in these wires. In this study, Nb/Al-Ge alloy composites were fabricated into multifilamentary wires through a modified jelly roll (MJR) process. A Nb mesh sheet produced at the Teledyne Wah Chang Co. was used as Nb component. An Al-Ge alloy prepared by a conventional casting process was forged and rolled into a sheet of 0.2 mm in thickness. The Nb/Al-Ge composite was prepared by wrapping the Nb mesh sheet together with the Al-Ge alloy sheet around amore » Nb core into a jelly roll form. The MJR composite was encased in a Cu-Ni alloy tube of which outer diameter was 43 mm. The resulting composite was hydrostatically pressed and extruded into a rod of 18 mm in diameter. A Nb barrier was then inserted between the MJR and the Cu-Ni jacket. The composite rod was swaged and drawn into a wire without any intermediate annealing. The wire was able to be drawn down to a very small diameter of 0.1 mm. The cross-sectional configuration of the MJR composite was not much disturbed by the fabrication. Superconducting transition temperature Tc of the wire, after different heat treatment including a rapid quenching from high temperatures by a continuous electron beam irradiation, was studied, and an onset Tc of 19.3K has been achieved.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Reese, A.P.; Crowther, R.L. Jr.
1992-02-18
This patent describes improvement in a boiling water reactor core having a plurality of vertically upstanding fuel bundles; each fuel bundle containing longitudinally extending sealed rods with fissile material therein; the improvement comprises the fissile material including a mixture of uranium and recovered plutonium in rods of the fuel bundle at locations other than the corners of the fuel bundle; and, neutron absorbing material being located in rods of the fuel bundle at rod locations adjacent the corners of the fuel bundles whereby the neutron absorbing material has decreased shielding from the plutonium and maximum exposure to thermal neutrons formore » shaping the cold reactivity shutdown zone in the fuel bundle.« less
Federal Register 2010, 2011, 2012, 2013, 2014
2011-12-20
... Steel Wire Rod From Mexico: Affirmative Preliminary Determination of Circumvention of the Antidumping.... SUMMARY: We preliminarily determine that carbon and certain alloy steel wire rod (wire rod) with an actual.... de C.V. (Deacero) is circumventing the antidumping duty order on wire rod from Mexico (Wire Rod Order...
An interactive wire-wrap board layout program
NASA Technical Reports Server (NTRS)
Schlutsmeyer, A.
1987-01-01
An interactive computer-graphics-based tool for specifying the placement of electronic parts on a wire-wrap circuit board is presented. Input is a data file (currently produced by a commercial logic design system) which describes the parts used and their interconnections. Output includes printed reports describing the parts and wire paths, parts counts, placement lists, board drawing, and a tape to send to the wire-wrap vendor. The program should reduce the engineer's layout time by a factor of 3 to 5 as compared to manual methods.
Large-scale transport across narrow gaps in rod bundles
DOE Office of Scientific and Technical Information (OSTI.GOV)
Guellouz, M.S.; Tavoularis, S.
1995-09-01
Flow visualization and how-wire anemometry were used to investigate the velocity field in a rectangular channel containing a single cylindrical rod, which could be traversed on the centreplane to form gaps of different widths with the plane wall. The presence of large-scale, quasi-periodic structures in the vicinity of the gap has been demonstrated through flow visualization, spectral analysis and space-time correlation measurements. These structures are seen to exist even for relatively large gaps, at least up to W/D=1.350 (W is the sum of the rod diameter, D, and the gap width). The above measurements appear to compatible with the fieldmore » of a street of three-dimensional, counter-rotating vortices, whose detailed structure, however, remains to be determined. The convection speed and the streamwise spacing of these vortices have been determined as functions of the gap size.« less
Two-phase pressure drop reduction BWR assembly design
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dix, G.E.; Crowther, R.L.; Colby, M.J.
1992-05-12
This patent describes a boiling water reactor having discrete bundles of fuel rods confined within channel enclosed fuel assemblies, an improvement to a fuel bundle assembly for placement in the reactor. It comprises a fuel channel having vertically extending walls forming a continuous channel around a fuel assembly volume, the channel being open at the bottom end for engagement to a lower tie plate and open at the upper end for engagement to an upper tie plate; rods for placement within the chamber, each the rod containing fissile material for producing nuclear reaction when in the presence of sufficient moderatedmore » neutron flux; a lower tie plate for supporting the bundle of rods within the channel, the lower tie plate for supporting the bundle of rods within the channel, the lower tie plate joining the bottom of the channel to close the bottom end of the channel, the lower tie plate providing defined apertures for the inflow of water in the channel between the rods for the generating of steam during the nuclear reaction; the plurality of fuel rods extending from the lower tie plate wherein a single phase region of the water in the bundle is defined to an upward portion of the bundle wherein a two phase region of the water and steam in the bundle is defined during nuclear steam generating reaction in the fuel bundle.« less
Elastocapillarity: When Surface Tension Deforms Elastic Solids
NASA Astrophysics Data System (ADS)
Bico, José; Reyssat, Étienne; Roman, Benoît
2018-01-01
Although negligible at large scales, capillary forces may become dominant for submillimetric objects. Surface tension is usually associated with the spherical shape of small droplets and bubbles, wetting phenomena, imbibition, or the motion of insects at the surface of water. However, beyond liquid interfaces, capillary forces can also deform solid bodies in their bulk, as observed in recent experiments with very soft gels. Capillary interactions, which are responsible for the cohesion of sandcastles, can also bend slender structures and induce the bundling of arrays of fibers. Thin sheets can spontaneously wrap liquid droplets within the limit of the constraints dictated by differential geometry. This review aims to describe the different scaling parameters and characteristic lengths involved in elastocapillarity. We focus on three main configurations, each characterized by a specific dimension: three-dimensional (3D), deformations induced in bulk solids; 1D, bending and bundling of rod-like structures; and 2D, bending and stretching of thin sheets. Although each configuration deserves a detailed review, we hope our broad description provides a general view of elastocapillarity.
75 FR 21658 - Carbon and Certain Alloy Steel Wire Rod From Trinidad and Tobago
Federal Register 2010, 2011, 2012, 2013, 2014
2010-04-26
... Certain Alloy Steel Wire Rod From Trinidad and Tobago AGENCY: United States International Trade Commission... Investigation No. 731-TA-961 concerning carbon and certain alloy steel wire rod (``wire rod'') from Trinidad and... of imports of wire rod from Trinidad and Tobago that were sold in the United States at less than fair...
78 FR 2658 - Carbon and Certain Alloy Steel Wire Rod From Mexico: Rescission of Antidumping Duty...
Federal Register 2010, 2011, 2012, 2013, 2014
2013-01-14
... Steel Wire Rod From Mexico: Rescission of Antidumping Duty Administrative Review; 2011-2012 AGENCY... order on carbon and certain alloy steel wire rod (``wire rod'') from Mexico for the period October 1... order on wire rod from Mexico for the period of review, October 1, 2011, through September 30, 2012.\\1...
Federal Register 2010, 2011, 2012, 2013, 2014
2012-03-07
... Steel Wire Rod From Mexico: Notice of Final Results of Antidumping Duty Administrative Review AGENCY... results of the administrative review of the antidumping duty order on carbon and certain alloy steel wire rod (wire rod) from Mexico.\\1\\ This review covers imports of wire rod from ArcelorMittal Las Truchas...
Federal Register 2010, 2011, 2012, 2013, 2014
2013-10-24
...-805, A-274-804, A-823-812] Carbon and Certain Alloy Steel Wire Rod From Brazil, Indonesia, Mexico... on carbon and certain alloy steel wire rod (``wire rod'') from Brazil, Indonesia, Mexico, Moldova... published the notice of initiation of the sunset reviews of the antidumping duty orders on wire rod from...
Improvements to Wire Bundle Thermal Modeling for Ampacity Determination
NASA Technical Reports Server (NTRS)
Rickman, Steve L.; Iannello, Christopher J.; Shariff, Khadijah
2017-01-01
Determining current carrying capacity (ampacity) of wire bundles in aerospace vehicles is critical not only to safety but also to efficient design. Published standards provide guidance on determining wire bundle ampacity but offer little flexibility for configurations where wire bundles of mixed gauges and currents are employed with varying external insulation jacket surface properties. Thermal modeling has been employed in an attempt to develop techniques to assist in ampacity determination for these complex configurations. Previous developments allowed analysis of wire bundle configurations but was constrained to configurations comprised of less than 50 elements. Additionally, for vacuum analyses, configurations with very low emittance external jackets suffered from numerical instability in the solution. A new thermal modeler is presented allowing for larger configurations and is not constrained for low bundle infrared emissivity calculations. Formulation of key internal radiation and interface conductance parameters is discussed including the effects of temperature and air pressure on wire to wire thermal conductance. Test cases comparing model-predicted ampacity and that calculated from standards documents are presented.
One-step internal-tin Nb/sub 3/Sn superconductor fabrication. Final report, June 1983-August 1984
DOE Office of Scientific and Technical Information (OSTI.GOV)
Marancik, W.
1985-03-01
The object of this research is to demonstrate the feasibility of producing a Nb/sub 3/Sn superconductor in a single extrusion process with a large number of filaments with internal tin. The technique chosen uses .010'-diameter Nb and tin-plated Cu wires formed into a solenoid. The solenoid is covered with tin-plated copper foil and isostatically compacted to a pressure of 17,000 psi. The solenoid is slit along its length. This results in a ribbon about 40 inches long by about 5-inches wide, with the Nb wires running across the 5-inch-width. The ribbon is then rolled up (Jelly Roll) around a 0.5more » inch diameter Ta covered copper rod to produce a composite of about 1.5 inches in diameter by 5 inches long. The composite geometry is now a cylindrical bundle of 0.010-inch-diameter Nb wire separated from each other by tin-plated copper. Each Nb wire is aligned with the axis of cylinder. The cylinder is slid into a Ta-lined copper extrusion can which is evacuated and sealed. The can is extruded at a low temperature and drawn to final wire size without intermediate annealing. The advantage of the process is that it is an internal tin process with the tin uniformly distributed through the matrix. The Nb is in a relatively soft state having been fully annealed at 0.020-inch diameter. Only one extrusion is required since the bundling technique allows a large number of wires to be precisely aligned and spaced in the matrix.« less
77 FR 3231 - Certain Stainless Steel Wire Rods From India: Continuation of Antidumping Duty Order
Federal Register 2010, 2011, 2012, 2013, 2014
2012-01-23
... DEPARTMENT OF COMMERCE International Trade Administration [A-533-808] Certain Stainless Steel Wire... antidumping duty order on certain stainless steel wire rods from India would likely lead to continuation or... reviews of the antidumping duty order on certain stainless steel wire rods (``wire rods'') from India,\\1...
Method of fabricating high-density hermetic electrical feedthroughs using insulated wire bundles
Shah, Kedar G.; Benett, William J.; Pannu, Satinderpall S.
2016-05-10
A method of fabricating electrical feedthroughs coats of a plurality of electrically conductive wires with an electrically insulating material and bundles the coated wires together in a substantially parallel arrangement. The bundled coated wires are secured to each other by joining the electrically insulating material of adjacent wires together to form a monolithic block which is then cut transverse to the wires to produce a block section having opposing first and second sides with a plurality of electrically conductive feedthroughs extending between them.
Method of bundling rods so as to form an optical fiber preform
Kliner, Dahv A. V. [San Ramon, CA; Koplow, Jeffery P [Washington, DC
2004-03-30
The present invention provides a simple method for fabricating fiber-optic glass preforms having complex refractive index configurations and/or dopant distributions in a radial direction with a high degree of accuracy and precision. The method teaches bundling together a plurality of glass rods of specific physical, chemical, or optical properties and wherein the rod bundle is fused in a manner that maintains the cross-sectional composition and refractive-index profiles established by the position of the rods.
Wrapped Wire Detects Rupture Of Pressure Vessel
NASA Technical Reports Server (NTRS)
Hunt, James B.
1990-01-01
Simple, inexpensive technique helps protect against damage caused by continuing operation of equipment after rupture or burnout of pressure vessel. Wire wrapped over area on outside of vessel where breakthrough most likely. If wall breaks or burns, so does wire. Current passing through wire ceases, triggering cutoff mechanism stopping flow in vessel to prevent further damage. Applied in other situations in which pipes or vessels fail due to overpressure, overheating, or corrosion.
NASA Astrophysics Data System (ADS)
Bayaskhalanov, M. V.; Vlasov, M. N.; Korsun, A. S.; Merinov, I. G.; Philippov, M. Ph
2017-11-01
Research results of “k-ε” turbulence integral model (TIM) parameters dependence on the angle of a coolant flow in regular smooth cylindrical rod-bundle are presented. TIM is intended for the definition of efficient impulse and heat transport coefficients in the averaged equations of a heat and mass transfer in the regular rod structures in an anisotropic porous media approximation. The TIM equations are received by volume-averaging of the “k-ε” turbulence model equations on periodic cell of rod-bundle. The water flow across rod-bundle under angles from 15 to 75 degrees was simulated by means of an ANSYS CFX code. Dependence of the TIM parameters on flow angle was as a result received.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-11-02
... DEPARTMENT OF COMMERCE International Trade Administration [A-533-808] Certain Stainless Steel Wire... duty order on certain stainless steel wire rods from India, pursuant to section 751(c) of the [[Page... antidumping duty order on certain stainless steel wire rods from India (wire rods) \\1\\ pursuant to section 751...
Federal Register 2010, 2011, 2012, 2013, 2014
2013-10-02
... Steel Wire Rod From Brazil: Final Results of the Expedited Second Sunset Review of the Countervailing... of the countervailing duty (CVD) order on carbon and certain alloy steel wire rod (wire rod) from...: Background On June 3, 2013, the Department initiated the second sunset review of the CVD order \\1\\ on wire...
Fuel bundle design for enhanced usage of plutonium fuel
Reese, Anthony P.; Stachowski, Russell E.
1995-01-01
A nuclear fuel bundle includes a square array of fuel rods each having a concentration of enriched uranium and plutonium. Each rod of an interior array of the rods also has a concentration of gadolinium. The interior array of rods is surrounded by an exterior array of rods void of gadolinium. By this design, usage of plutonium in the nuclear reactor is enhanced.
Fuel bundle design for enhanced usage of plutonium fuel
Reese, A.P.; Stachowski, R.E.
1995-08-08
A nuclear fuel bundle includes a square array of fuel rods each having a concentration of enriched uranium and plutonium. Each rod of an interior array of the rods also has a concentration of gadolinium. The interior array of rods is surrounded by an exterior array of rods void of gadolinium. By this design, usage of plutonium in the nuclear reactor is enhanced. 10 figs.
75 FR 32503 - Stainless Steel Wire Rod From Italy, Japan, Korea, Spain, and Taiwan
Federal Register 2010, 2011, 2012, 2013, 2014
2010-06-08
...)] Stainless Steel Wire Rod From Italy, Japan, Korea, Spain, and Taiwan Determinations On the basis of the... revocation of the antidumping duty orders on stainless steel wire rod from Italy, Japan, Korea, Spain, and... USITC Publication 4154 (May 2010), entitled Stainless Steel Wire Rod from Italy, Japan, Korea, Spain...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Loftus, M J; Hochreiter, L E; McGuire, M F
This report presents data from the 163-Rod Bundle Blow Blockage Task of the Full-Length Emergency Cooling Heat Transfer Systems Effects and Separate Effects Test Program (FLECHT SEASET). The task consisted of forced and gravity reflooding tests utilizing electrical heater rods with a cosine axial power profile to simulate PWR nuclear core fuel rod arrays. These tests were designed to determine effects of flow blockage and flow bypass on reflooding behavior and to aid in the assessment of computational models in predicting the reflooding behavior of flow blockage in rod bundle arrays.
Miniature, shielded electrical connector with strain relief
NASA Technical Reports Server (NTRS)
Diep, Chuong H. (Inventor)
2006-01-01
An electrical connector assembly includes a wire bundle having at least one wire with a metal shield surrounding at least a portion of the wire. The shield has an end portion and provides electromagnetic interference protection to the wire. A backshell includes a body and a cover secured to the body together defining an internal cavity with the wire at least partially arranged within the cavity. The backshell provides EMI protection for the portion of the wire bundle not covered by the shield. The backshell includes a hole in a wall of either the body or the cover with the end portion of the shield extending through the hole. The clamp is secured about the body and the cover with the end portion of the shield arranged between the clamp and the backshell grounding the shield to the backshell. The clamp forces the backshell into engagement with the wire bundle to provide strain relief for the wire bundle.
A retracting wire knife for cutting fiber bundles and making sheet lesions of brain tissue.
Shibata, M; Russell, I S
1979-07-01
A retracting knife which has two cutting wires for the transection of fiber bundles is described. The knife holds the fiber bundles of the stria terminalis between the two cutting wires and transects them by a shearing movement as the wires close. In addition, the feasability of such a knife producing a sheet lesion around the n. caudatus is also described.
Federal Register 2010, 2011, 2012, 2013, 2014
2013-05-14
... Steel Wire Rod From Mexico: Final Results of Antidumping Duty Administrative Review; 2010-2011 AGENCY... results of the administrative review of the antidumping duty order on carbon and certain alloy steel wire rod (wire rod) from Mexico. The period of review (POR) is October 1, 2010, through September 30, 2011...
Federal Register 2010, 2011, 2012, 2013, 2014
2012-11-08
... Steel Wire Rod From Mexico: Preliminary Results of Antidumping Duty Administrative Review; 2010-2011... conducting an administrative review of the antidumping duty order on carbon and certain alloy steel wire rod (wire rod) from Mexico. The period of review is October 1, 2010, through September 30, 2011, and the...
Federal Register 2010, 2011, 2012, 2013, 2014
2013-10-01
... (Second Review)] Carbon and Certain Alloy Steel Wire Rod From Brazil, Indonesia, Mexico, Moldova, Trinidad... certain alloy steel wire rod from Brazil and antidumping duty orders on carbon and certain alloy steel... reviews of the antidumping duty order on carbon and certain alloy steel wire rod from Mexico. The...
Federal Register 2010, 2011, 2012, 2013, 2014
2013-12-18
... 962 (Second Review)] Carbon and Certain Alloy Steel Wire Rod From Brazil, Indonesia, Mexico, Moldova... orders on carbon and certain alloy steel wire rod from Brazil, Indonesia, Mexico, Moldova, Trinidad and... carbon and certain alloy steel wire rod from Brazil, Indonesia, Mexico, Moldova, Trinidad and Tobago, and...
75 FR 51701 - Airworthiness Directives; Learjet Inc. Model 45 Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2010-08-23
... configuration of the engine and alternator wire harnesses, and the starter/generator wire bundles. For certain... necessary. For certain airplanes, inspecting for clearance between the wire harnesses and the hydraulic and... wire harnesses and the starter/generator wire bundles. (2) Do a detailed inspection for chafing damage...
NASA Technical Reports Server (NTRS)
Fisch, G. Z.; Borden, T. J.
1982-01-01
Monitoring circuit responds to changes in resistance as little as 0.1 ohm. Has been used to detect defective wire-wrap connections during thermal and vibration tests. Defect is indicated to operator by light-emitting diode and by increase in count on a two-digit display.
Using the HELIOS facility for assessment of bundle-jacket thermal coupling in a CICC
NASA Astrophysics Data System (ADS)
Lacroix, B.; Rousset, B.; Cloez, H.; Decool, P.; Duchateau, J. L.; Hoa, C.; Luchier, N.; Nicollet, S.; Topin, F.
2016-12-01
In a Cable In Conduit Conductor (CICC) cooled by forced circulation of supercritical helium, the heat exchange in the bundle region can play a significant role for conductor safe operation, while remaining a quite uncertain parameter. Heat exchange between bundle and jacket depends on the relative contributions of convective heat transfer due to the helium flow inside the bundle and of thermal resistance due to the wrappings between the cable and the conduit. In order to qualify this thermal coupling at realistic operating conditions, a dedicated experiment on a 1.2 m sample of ITER Toroidal Field (TF) dummy conductor was designed and performed in the HELIOS test facility at CEA Grenoble. Several methods were envisaged, and the choice was made to assess bundle-jacket heat transfer coefficient by measuring the temperature of a solid copper cylinder inserted over the conductor jacket and submitted to heat deposition on its outer surface. The mock-up was manufactured and tested in spring 2015. Bundle-jacket heat transfer coefficient was found in the range 300-500 W m-2 K-1. Results analysis suggests that the order of magnitude of convective heat transfer coefficient inside bundle is closer to Colburn-Reynolds analogy than to Dittus-Boelter correlation, and that bundle-jacket thermal coupling is mainly limited by thermal resistance due to wrappings. A model based on an equivalent layer of stagnant helium between wraps and jacket was proposed and showed a good consistency with the experiment, with relevant values for the helium layer thickness.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-08-24
... the compliance times specified, unless already done. Installation of New Relay and Wiring Bundle (g... certain wiring changes, installing a new relay and necessary wiring in the cabin air conditioning and... for changing the wire bundle route and wiring, installing a new relay and applicable wiring in the...
Federal Register 2010, 2011, 2012, 2013, 2014
2010-06-17
...-807, A-583-828] Stainless Steel Wire Rod from Italy, Japan, the Republic of Korea, Spain, and Taiwan... stainless steel wire rod (SSWR) from Italy, Japan, the Republic of Korea (Korea), Spain, and Taiwan would... magnitude of the margins likely to prevail should the orders be revoked. See Stainless Steel Wire Rod From...
Direct-Current Monitor With Flux-Reset Transformer Coupling
NASA Technical Reports Server (NTRS)
Canter, Stanley
1993-01-01
Circuit measures constant or slowly-varying unidirectional electrical current using flux-reset transformer coupling. Measurement nonintrusive in sense that no need for direct contact with wire that carries load current to be measured, and no need to install series resistive element in load-current path. Toroidal magnetic core wrapped with coil of wire placed around load-current-carrying wire, acts as transformer core, load-current-carrying wire acts as primary winding of transformer, and coil wrapped on core acts as secondary winding.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-06-08
... Steel Wire Rod From Mexico: Initiation of Anti-Circumvention Inquiry of Antidumping Duty Order AGENCY..., under 19 CFR 351.225(k)(2) to determine whether wire rod with an actual diameter between 4.75 and 5.00 millimeters (mm) is within the scope of the antidumping (AD) order on carbon and certain alloy steel wire rod...
Federal Register 2010, 2011, 2012, 2013, 2014
2011-10-05
... AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Final rule. SUMMARY: We are adopting a new... clearance and any wire bundle damage between wire bundle W443 and the left forward rudder quadrant, followed by adjusting the minimum clearance between the wire bundle and the left forward rudder quadrant, and...
Federal Register 2010, 2011, 2012, 2013, 2014
2011-01-18
...: We propose to adopt a new airworthiness directive (AD) for certain Model 737-600, -700, -700C, -800... and any wire bundle damage between wire bundle W443 and the left forward rudder quadrant, followed by adjusting the minimum clearance between the wire bundle and the left forward rudder quadrant, and repairing...
77 FR 1504 - Stainless Steel Wire Rod From India
Federal Register 2010, 2011, 2012, 2013, 2014
2012-01-10
... INTERNATIONAL TRADE COMMISSION [Investigation No. 731-TA-638 (Third Review)] Stainless Steel Wire... stainless steel wire rod From India would be likely to lead to continuation or recurrence of material injury... USITC Publication 4300 (January 2012), entitled Stainless Steel Wire Rod From India: Investigation No...
Thermal Control Method for High-Current Wire Bundles by Injecting a Thermally Conductive Filler
NASA Technical Reports Server (NTRS)
Rodriguez-Ruiz, Juan; Rowles, Russell; Greer, Greg
2011-01-01
A procedure was developed to inject thermal filler material (a paste-like substance) inside the power wire bundle coming from solar arrays. This substance fills in voids between wires, which enhances the heat path and reduces wire temperature. This leads to a reduced amount of heat generated. This technique is especially helpful for current and future generation high-power spacecraft (1 kW or more), because the heat generated by the power wires is significant enough to cause unacceptable overheating to critical components that are in close contact with the bundle.
2016-09-01
10 Fig. 8 Lithium ion polymer battery .................................................................. 11 Fig. 9 PowerBoost 1000C (right) and...7]. http://www.adafruit.com/products/1552. 7. Lithium Ion Polymer Battery –3.7v 2500mAh. [accessed Jul 7]. https://www.adafruit.com/products/328. 8...port directly) RealTek RT5370 Wi-Fi USB adapter 1 Wire-wrapping wires . . . Wire-wrap hand tool . . . Soldering kit . . . alipo: lithium - ion
Federal Register 2010, 2011, 2012, 2013, 2014
2011-10-17
... INTERNATIONAL TRADE COMMISSION [Investigation No. 731-TA-638 (Third Review)] Stainless Steel Wire... Stainless Steel Wire Rod From India AGENCY: United States International Trade Commission. ACTION: Notice... of the antidumping duty order on stainless steel wire rod from India would be likely to lead to...
Strength of cerclage fixation systems: a biomechanical study.
Incavo, S J; Difazio, F; Wilder, D
1990-11-01
This study examined the load to failure ratio and stiffness of eight different cerclage techniques commonly used in the clinical management of fractures. For a single-loop cerclage, titanium cable was the strongest, while stainless steel wire secured with a commercial tightener was the weakest (P < 0.05). When a single-loop configuration is necessary (i.e. trochanteric attachment) a cable system is superior to cerclage wiring. A double-wrap of either cable or wire was considerably stronger than any single-wrap cerclage technique and stronger than two cerclage wires (P < 0.05). Copyright © 1990. Published by Elsevier Ltd.
Validated simulator for space debris removal with nets and other flexible tethers applications
NASA Astrophysics Data System (ADS)
Gołębiowski, Wojciech; Michalczyk, Rafał; Dyrek, Michał; Battista, Umberto; Wormnes, Kjetil
2016-12-01
In the context of active debris removal technologies and preparation activities for the e.Deorbit mission, a simulator for net-shaped elastic bodies dynamics and their interactions with rigid bodies, has been developed. Its main application is to aid net design and test scenarios for space debris deorbitation. The simulator can model all the phases of the debris capturing process: net launch, flight and wrapping around the target. It handles coupled simulation of rigid and flexible bodies dynamics. Flexible bodies were implemented using Cosserat rods model. It allows to simulate flexible threads or wires with elasticity and damping for stretching, bending and torsion. Threads may be combined into structures of any topology, so the software is able to simulate nets, pure tethers, tether bundles, cages, trusses, etc. Full contact dynamics was implemented. Programmatic interaction with simulation is possible - i.e. for control implementation. The underlying model has been experimentally validated and due to significant gravity influence, experiment had to be performed in microgravity conditions. Validation experiment for parabolic flight was a downscaled process of Envisat capturing. The prepacked net was launched towards the satellite model, it expanded, hit the model and wrapped around it. The whole process was recorded with 2 fast stereographic camera sets for full 3D trajectory reconstruction. The trajectories were used to compare net dynamics to respective simulations and then to validate the simulation tool. The experiments were performed on board of a Falcon-20 aircraft, operated by National Research Council in Ottawa, Canada. Validation results show that model reflects phenomenon physics accurately enough, so it may be used for scenario evaluation and mission design purposes. The functionalities of the simulator are described in detail in the paper, as well as its underlying model, sample cases and methodology behind validation. Results are presented and typical use cases are discussed showing that the software may be used to design throw nets for space debris capturing, but also to simulate deorbitation process, chaser control system or general interactions between rigid and elastic bodies - all in convenient and efficient way. The presented work was led by SKA Polska under the ESA contract, within the CleanSpace initiative.
Method for making a hot wire anemometer and product thereof
NASA Technical Reports Server (NTRS)
Milkulla, V. (Inventor)
1977-01-01
A hot wire anemometer probe is described that includes a ceramic body supporting two conductive rods parallel to each other. The body has a narrow edge surface from which the rods protrude. A probe wire is welded to the rods and extends along the edge surface. A ceramic adhesive is used to secure the probe wire to the surface so that the probe wire is rigid. A method for fabricating the probe is also described in which the body is molded and precisely shaped by machining techniques before the probe wires are installed.
Resistance Heater Helps Stirling-Engine Research
NASA Technical Reports Server (NTRS)
Hoehn, F. W.
1982-01-01
Stirling engine heater head consists of 18 double-turn coils of tubing, each of which is tightly wrapped with resistance-heating element, through which working gas flows. Coils form a toroid about periphery of heater-head body. With new resistance heater, total circuit resistance can be selected independently of tube geometry by changing size of wires and/or number of wire wraps around each tube.
Method of fabricating a homogeneous wire of inter-metallic alloy
Ohriner, Evan Keith; Blue, Craig Alan
2001-01-01
A method for fabricating a homogeneous wire of inter-metallic alloy comprising the steps of providing a base-metal wire bundle comprising a metal, an alloy or a combination thereof; working the wire bundle through at least one die to obtain a desired dimension and to form a precursor wire; and, controllably heating the precursor wire such that a portion of the wire will become liquid while simultaneously maintaining its desired shape, whereby substantial homogenization of the wire occurs in the liquid state and additional homogenization occurs in the solid state resulting in a homogenous alloy product.
Method of fabricating composite superconducting wire
Strauss, Bruce P.; Reardon, Paul J.; Remsbottom, Robert H.
1977-01-01
An improvement in the method for preparing composite rods of superconducting alloy and normal metal from which multifilament composite superconducting wire is fabricated by bending longitudinally a strip of normal metal around a rod of superconductor alloy and welding the edges to form the composite rod. After the rods have preferably been provided with a hexagonal cross-sectional shape, a plurality of the rods are stacked into a normal metal extrusion can, sealed and worked to reduce the cross-sectional size and form multifilament wire. Diffusion barriers and high-electrical resistance barriers can easily be introduced into the wire by plating or otherwise coating the faces of the normal metal strip with appropriate materials.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Frankhouser, W.L.; Eyler, J.H.
1956-07-24
Five reference fuel rod bundles were welded and evaluated dimensionally. Dimensional data are presented for the as-welded condition and for the annealed bundle with spacer strips removed (prior to the final machining operations). The welding sequence developed for Core Manufacturing should provide A'' boundles in respect to rod spacing measurements. It will probably not be possible to meet the same requirements for water channel averages, because the design tolerances are not consistent with some factors inherent to the production process. A method to improve this situation is presented. The data presented were evaluated in a fashion similar to that whichmore » would be used in the proposed scheme. Rods tended to bow resulting in a slightly barrel-shaped'' boundle. It is believed this condition can be overcome by providing special bundle peripheral clamps during annealing. Rod distortion should also be reduced by a redesign and relocation of strip spacers. The new design is proposed. (auth)« less
75 FR 7557 - Airworthiness Directives; The Boeing Company Model 767 Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2010-02-22
... shorts in many systems, including the spar fuel shut off valve, oxygen mask deployment, and burned wires... and wire bundles, causing shorts in many systems, including the spar fuel shut off valve, oxygen mask... and wire bundles, causing shorts in many systems, including the spar fuel shut off valve, oxygen mask...
Federal Register 2010, 2011, 2012, 2013, 2014
2011-06-10
... DEPARTMENT OF COMMERCE International Trade Administration [A-201-830] Carbon and Certain Alloy Steel Wire Rod From Mexico: Extension of Time Limits for the Preliminary Results of Fifth Antidumping... carbon and certain alloy steel wire rod from Mexico, covering the period October 1, 2009, through...
Tubular hydrogen permeable metal foil membrane and method of fabrication
Paglieri, Stephen N.; Birdsell, Stephen A.; Barbero, Robert S.; Snow, Ronny C.; Smith, Frank M.
2006-04-04
A tubular hydrogen permeable metal membrane and fabrication process comprises obtaining a metal alloy foil having two surfaces, coating the surfaces with a metal or metal alloy catalytic layer to produce a hydrogen permeable metal membrane, sizing the membrane into a sheet with two long edges, wrapping the membrane around an elongated expandable rod with the two long edges aligned and overlapping to facilitate welding of the two together, placing the foil wrapped rod into a surrounding fixture housing with the two aligned and overlapping foil edges accessible through an elongated aperture in the surrounding fixture housing, expanding the elongated expandable rod within the surrounding fixture housing to tighten the foil about the expanded rod, welding the two long overlapping foil edges to one another generating a tubular membrane, and removing the tubular membrane from within the surrounding fixture housing and the expandable rod from with the tubular membrane.
Difazio, F A; Incavo, S J; Howe, J D
1993-09-01
This study examined the effect of single versus triple-wrap cerclage fixation techniques in preventing propagation of a longitudinal fracture around a cementless femoral prosthesis. A proximal filling femoral component was implanted in 14 matched pairs of fresh-frozen bovine femora, following placement of a 45-mm longitudinal crack in the anteromedial cortical wall of the proximal femur. In one group of seven pairs, a single cerclage wire was applied to one specimen of each pair. A triple-wrap of a single cerclage wire was similarly placed in one specimen of each of the other seven pairs. All specimens were axially loaded on a materials testing system machine and the force required to propagate the fracture of the proximal femur was recorded. A triple-wrap cerclage technique required a significant increase in the force to propagate a proximal femur fracture around a non-cemented prosthesis when compared to a single cerclage wire. Copyright © 1993. Published by Elsevier Ltd.
Single-wire dye-sensitized solar cells wrapped by carbon nanotube film electrodes.
Zhang, Sen; Ji, Chunyan; Bian, Zhuqiang; Liu, Runhua; Xia, Xinyuan; Yun, Daqin; Zhang, Luhui; Huang, Chunhui; Cao, Anyuan
2011-08-10
Conventional fiber-shaped polymeric or dye-sensitized solar cells (DSSCs) are usually made into a double-wire structure, in which a secondary electrode wire (e.g., Pt) was twisted along the primary core wire consisting of active layers. Here, we report highly flexible DSSCs based on a single wire, by wrapping a carbon nanotube film around Ti wire-supported TiO(2) tube arrays as the transparent electrode. Unlike a twisted Pt electrode, the CNT film ensures full contact with the underlying active layer, as well as uniform illumination along circumference through the entire DSSC. The single-wire DSSC shows a power conversion efficiency of 1.6% under standard illumination (AM 1.5, 100 mW/cm(2)), which is further improved to more than 2.6% assisted by a second conventional metal wire (Ag or Cu). Our DSSC wires are stable and can be bent to large angles up to 90° reversibly without performance degradation.
Material distribution in light water reactor-type bundles tested under severe accident conditions
DOE Office of Scientific and Technical Information (OSTI.GOV)
Noack, V.; Hagen, S.J.L.; Hofmann, P.
1997-02-01
Severe fuel damage experiments simulating small-break loss-of-coolant accidents have been carried out in the CORA out-of-pile test facility at Forschungszentrum Karlsruhe. Rod bundles with electrically heated fuel rod simulators containing annular UO{sub 2} pellets, UO{sub 2} full pellet rods, and absorber rods of two kinds (Ag/In/Cd to represent pressurized water reactor conditions and B{sub 4}C to represent boiling water reactor and VVER-1000 fuel elements) were subjected to temperature transients up to 2,300 K. A special method was applied to determine the axial mass distribution of bundle materials. The low-temperature melt formation by various interactions between zirconium and components of absorbermore » and spacer grids strongly influences the bundle degradation and material relocation. Absorber materials can separate from the fuel by a noncoherent relocation of the materials at different temperatures. The distributions of solidified materials in the different test bundles show a clear dependence on the axial temperature profile. Coolant channel blockages are observed mainly at the lower end of the bundle, i.e., near the lowest elevation at which an oxidation excursion resulting from the highly exothermic zirconium-steam reaction had been experienced. This elevation corresponds with a steep axial temperature gradient in the maximum temperature attained. Oxide layers on Zircaloy result in reduced melt formation.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jeong, Hae-Yong; Ha, Kwi-Seok; Chang, Won-Pyo
The local blockage in a subassembly of a liquid metal-cooled reactor (LMR) is of importance to the plant safety because of the compact design and the high power density of the core. To analyze the thermal-hydraulic parameters in a subassembly of a liquid metal-cooled reactor with a flow blockage, the Korea Atomic Energy Research Institute has developed the MATRA-LMR-FB code. This code uses the distributed resistance model to describe the sweeping flow formed by the wire wrap around the fuel rods and to model the recirculation flow after a blockage. The hybrid difference scheme is also adopted for the descriptionmore » of the convective terms in the recirculating wake region of low velocity. Some state-of-the-art turbulent mixing models were implemented in the code, and the models suggested by Rehme and by Zhukov are analyzed and found to be appropriate for the description of the flow blockage in an LMR subassembly. The MATRA-LMR-FB code predicts accurately the experimental data of the Oak Ridge National Laboratory 19-pin bundle with a blockage for both the high-flow and low-flow conditions. The influences of the distributed resistance model, the hybrid difference method, and the turbulent mixing models are evaluated step by step with the experimental data. The appropriateness of the models also has been evaluated through a comparison with the results from the COMMIX code calculation. The flow blockage for the KALIMER design has been analyzed with the MATRA-LMR-FB code and is compared with the SABRE code to guarantee the design safety for the flow blockage.« less
Preform For Producing An Optical Fiber And Method Therefor
Kliner, Dahv A. V.; Koplow, Jeffery P.
2004-08-10
The present invention provides a simple method for fabricating fiber-optic glass preforms having complex refractive index configurations and/or dopant distributions in a radial direction with a high degree of accuracy and precision. The method teaches bundling together a plurality of glass rods of specific physical, chemical, or optical properties and wherein the rod bundle is fused in a manner that maintains the cross-sectional composition and refractive-index profiles established by the position of the rods.
Preform For Producing An Optical Fiber And Method Therefor
Kliner, Dahv A. V.; Koplow, Jeffery P.
2005-04-19
The present invention provides a simple method for fabricating fiber-optic glass preforms having complex refractive index configurations and/or dopant distributions in a radial direction with a high degree of accuracy and precision. The method teaches bundling together a plurality of glass rods of specific physical, chemical, or optical properties and wherein the rod bundle is fused in a manner that maintains the cross-sectional composition and refractive-index profiles established by the position of the rods.
Wang, S.T.
1994-11-01
A wire cable assembly adapted for the winding of electrical coils is taught. A primary intended use is for use in particle tube assemblies for the Superconducting Super Collider. The correction coil cables have wires collected in wire array with a center rib sandwiched therebetween to form a core assembly. The core assembly is surrounded by an assembly housing having an inner spiral wrap and a counter wound outer spiral wrap. An alternate embodiment of the invention is rolled into a keystoned shape to improve radial alignment of the correction coil cable on a particle tube in a particle tube assembly. 7 figs.
Hirsch, Gregory
2002-01-01
A plurality of glass or metal wires are precisely etched to form the desired shape of the individual channels of the final polycapillary optic. This shape is created by carefully controlling the withdrawal speed of a group of wires from an etchant bath. The etched wires undergo a subsequent operation to create an extremely smooth surface. This surface is coated with a layer of material which is selected to maximize the reflectivity of the radiation being used. This reflective surface may be a single layer of material, or a multilayer coating for optimizing the reflectivity in a narrower wavelength interval. The collection of individual wires is assembled into a close-packed multi-wire bundle, and the wires are bonded together in a manner which preserves the close-pack configuration, irrespective of the local wire diameter. The initial wires are then removed by either a chemical etching procedure or mechanical force. In the case of chemical etching, the bundle is generally segmented by cutting a series of etching slots. Prior to removing the wire, the capillary array is typically bonded to a support substrate. The result of the process is a bundle of precisely oriented radiation-reflecting hollow channels. The capillary optic is used for efficiently collecting and redirecting the radiation from a source of radiation which could be the anode of an x-ray tube, a plasma source, the fluorescent radiation from an electron microprobe, a synchrotron radiation source, a reactor or spallation source of neutrons, or some other source.
Roe, S C
1997-01-01
Evaluate the mechanical properties of twist, loop, double loop, double-wrap and loop/twist cerclage. The initial tension generated by 18 cerclage of each type was determined using a materials testing machine after tying around a testing jig. Six wires from each type were distracted and the initial stiffness and yield load were determined. Yield behavior was further investigated in six wires of each type by determining the load required to reduce cerclage tension below 30 Newton (N) following and incremental (50 N) stepwise load and unload regimen. The amount of collapse of the simulated bone fragments that resulted in the reduction of initial tension to 30 N was measured for the final six wires of each group. Data were analyzed by analysis of variance and a multiple comparison test. Twist type cerclage generated less tension than loop-type cerclage. The yield load of these two types was similar. Double-loop and double-wrap cerclage generated superior tension and resisted a greater load before loosening. Loop/twist cerclage had an intermediate initial tension but had the greatest resistance to loading. In the collapse test, the greater the initial tension, the more collapse could occur before the wire was loose. For all types of cerclage wire fixation, a reduction of diameter of the testing jig of more than 1% caused loosening. Double-loop and double-wrap cerclage provide greater compression of fragments and resist loads associated with weight-bearing better than the twist and loop methods. Loop/twist cerclage may have advantages because of their superior resistance to loading. All cerclage will loosen if fracture fragments collapse.
NASA Technical Reports Server (NTRS)
Lundquist, Ray A.; Leidecker, Henning
1998-01-01
The allowable operating currents of electrical wiring when used in the space vacuum environment is predominantly determined by the maximum operating temperature of the wire insulation. For Kapton insulated wire this value is 200 C. Guidelines provided in the Goddard Space Flight Center (GSFC) Preferred Parts List (PPL) limit the operating current of wire within vacuum to ensure the maximum insulation temperature is not exceeded. For 20 AWG wire, these operating parameters are: 3.7 amps per wire, bundle of 15 or more wires, 70 C environment, and vacuum of 10(exp -5) torr or less. To determine the behavior and temperature of electrical wire at different operating conditions, a thermal vacuum test was performed on a representative electrical harness of the Hubble Space Telescope (HST) power distribution system. This paper describes the test and the results.
ERIC Educational Resources Information Center
Vance, Shelly
2012-01-01
In this article, the author describes how her students constructed a three-dimensional sculpture of a dragon using plaster wrap and other materials. The dragons were formed from modest means--using only a toilet-paper tube, newsprint, tape and wire.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Corradini, Michael; Wu, Qiao
2015-04-30
This report is a preliminary document presenting an overview of the Critical Heat Flux (CHF) phenomenon, the High Pressure Critical Heat Flux facility (HPCHF), preliminary CHF data acquired, and the future direction of the research. The HPCHF facility has been designed and built to study CHF at high pressure and low mass flux ranges in a rod bundle prototypical of conceptual Small Modular Reactor (SMR) designs. The rod bundle is comprised of four electrically heated rods in a 2x2 square rod bundle with a prototypic chopped-cosine axial power profile and equipped with thermocouples at various axial and circumferential positions embeddedmore » in each rod for CHF detection. Experimental test parameters for CHF detection range from pressures of ~80 – 160 bar, mass fluxes of ~400 – 1500 kg/m2s, and inlet water subcooling from ~30 – 70°C. The preliminary data base established will be further extended in the future along with comparisons to existing CHF correlations, models, etc. whose application ranges may be applicable to the conditions of SMRs.« less
Application Of Numerical Modelling To Ribbed Wire Rod Dimensions Precision Increase
NASA Astrophysics Data System (ADS)
Szota, Piotr; Mróz, Sebastian; Stefanik, Andrzej
2007-05-01
The paper presents the results of theoretical and experimental investigations of the process of rolling square ribbed wire rod designed for concrete reinforcement. Numerical modelling of the process of rolling in the finishing and pre-finishing grooves was carried out using the Forge2005® software. In the investigation, particular consideration was given to the analysis of the effect of pre-finished band shape on the formation of ribs on the finished wire rod in the finishing groove. The results of theoretical studies were verified in experimental tests, which were carried out in a wire rolling mill.
Void fraction distribution in a heated rod bundle under flow stagnation conditions
DOE Office of Scientific and Technical Information (OSTI.GOV)
Herrero, V.A.; Guido-Lavalle, G.; Clausse, A.
1995-09-01
An experimental study was performed to determine the axial void fraction distribution along a heated rod bundle under flow stagnation conditions. The development of the flow pattern was investigated for different heat flow rates. It was found that in general the void fraction is overestimated by the Zuber & Findlay model while the Chexal-Lellouche correlation produces a better prediction.
NASA Technical Reports Server (NTRS)
Lundquist, Ray A.; Leidecker, Henning
1999-01-01
The allowable operating currents of electrical wiring when used in the space vacuum environment is predominantly determined by the maximum operating temperature of the wire insulation. For Kapton insulated wire this value is 200 degree C. Guidelines provided in the Goddard Space Flight Center (GSFC) Preferred Parts List (PPL) limit the operating current of wire within vacuum to ensure the maximum insulation temperature is not exceeded. For 20 AWG wire, these operating parameters are: (1) 3.7 amps per wire (2) bundle of 15 or more wires (3) 70 C environment (4) vacuum of 10(exp -5) torr or less To determine the behavior and temperature of electrical wire at different operating conditions, a thermal vacuum test was performed on a representative electrical harness of the Hubble Space Telescope (HST) power distribution system. This paper describes the test and the results.
NASA Technical Reports Server (NTRS)
Lundquist, Ray A.; Leidecker, Henning
1998-01-01
The allowable operating currents of electrical wiring when used in the space vacuum environment is predominantly determined by the maximum operating temperature of the wire insulation. For Kapton insulated wire this value is 200 C. Guidelines provided in the Goddard Space Flight Center (GSFC) Preferred Parts List (PPL) limit the operating current of wire within vacuum to ensure the maximum insulation temperature is not exceeded. For 20 AWG wire, these operating parameters are: (1) 3.7 amps per wire; (2) bundle of 15 or more wires; (3) 70 C environment: and (4) vacuum of 10(exp -5) torr or less. To determine the behavior and temperature of electrical wire at different operating conditions, a thermal vacuum test was performed on a representative electrical harness of the Hubble Space Telescope (HST) power distribution system. This paper describes the test and the results.
21 CFR 872.4600 - Intraoral ligature and wire lock.
Code of Federal Regulations, 2014 CFR
2014-04-01
...) Identification. An intraoral ligature and wire lock is a metal device intended to constrict fractured bone segments in the oral cavity. The bone segments are stabilized by wrapping the ligature (wire) around the fractured bone segments and locking the ends together. (b) Classification. Class II. ...
21 CFR 872.4600 - Intraoral ligature and wire lock.
Code of Federal Regulations, 2010 CFR
2010-04-01
...) Identification. An intraoral ligature and wire lock is a metal device intended to constrict fractured bone segments in the oral cavity. The bone segments are stabilized by wrapping the ligature (wire) around the fractured bone segments and locking the ends together. (b) Classification. Class II. ...
21 CFR 872.4600 - Intraoral ligature and wire lock.
Code of Federal Regulations, 2013 CFR
2013-04-01
...) Identification. An intraoral ligature and wire lock is a metal device intended to constrict fractured bone segments in the oral cavity. The bone segments are stabilized by wrapping the ligature (wire) around the fractured bone segments and locking the ends together. (b) Classification. Class II. ...
21 CFR 872.4600 - Intraoral ligature and wire lock.
Code of Federal Regulations, 2012 CFR
2012-04-01
...) Identification. An intraoral ligature and wire lock is a metal device intended to constrict fractured bone segments in the oral cavity. The bone segments are stabilized by wrapping the ligature (wire) around the fractured bone segments and locking the ends together. (b) Classification. Class II. ...
21 CFR 872.4600 - Intraoral ligature and wire lock.
Code of Federal Regulations, 2011 CFR
2011-04-01
...) Identification. An intraoral ligature and wire lock is a metal device intended to constrict fractured bone segments in the oral cavity. The bone segments are stabilized by wrapping the ligature (wire) around the fractured bone segments and locking the ends together. (b) Classification. Class II. ...
NASA Technical Reports Server (NTRS)
Brudnicki, Myron (Inventor)
1995-01-01
Rotary actuators and other mechanical devices incorporating shape memory alloys are provided herein. Shape memory alloys are a group of metals which when deformed at temperatures below their martensite temperatures, resume the shapes which they had prior to the deformation if they are heated to temperatures above their austensite temperatures. Actuators in which shape memory alloys are employed include bias spring types, in which springs deform the shape memory alloy (SMA), and differential actuators, which use two SMA members mechanically connected in series. Another type uses concentric cylindrical members. One member is in the form of a sleeve surrounding a cylinder, both being constructed of shape memory alloys. Herein two capstans are mounted on a shaft which is supported in a framework. Each capstan is capable of rotating the shaft. Shape memory wire, as two separate lengths of wire, is wrapped around each capstan to form a winding around that capstan. The winding on one capstan is so wrapped that the wire is in a prestretched state. The winding on the other capstan is so wrapped that the wire is in a taut, but not a prestretched, state. Heating one performs work in one direction, thus deforming the other one. When the other SMA is heated the action is reversed.
High-performance, stretchable, wire-shaped supercapacitors.
Chen, Tao; Hao, Rui; Peng, Huisheng; Dai, Liming
2015-01-07
A general approach toward extremely stretchable and highly conductive electrodes was developed. The method involves wrapping a continuous carbon nanotube (CNT) thin film around pre-stretched elastic wires, from which high-performance, stretchable wire-shaped supercapacitors were fabricated. The supercapacitors were made by twisting two such CNT-wrapped elastic wires, pre-coated with poly(vinyl alcohol)/H3PO4 hydrogel, as the electrolyte and separator. The resultant wire-shaped supercapacitors exhibited an extremely high elasticity of up to 350% strain with a high device capacitance up to 30.7 F g(-1), which is two times that of the state-of-the-art stretchable supercapacitor under only 100% strain. The wire-shaped structure facilitated the integration of multiple supercapacitors into a single wire device to meet specific energy and power needs for various potential applications. These supercapacitors can be repeatedly stretched from 0 to 200% strain for hundreds of cycles with no change in performance, thus outperforming all the reported state-of-the-art stretchable electronics. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
PWR integral tie plate and locking mechanism
DOE Office of Scientific and Technical Information (OSTI.GOV)
Flora, B.S.; Osborne, J.L.
1980-08-26
A locking mechanism for securing an upper tie plate to the tie rods of a nuclear fuel bundle is described. The mechanism includes an upper tie plate assembly and locking sleeves fixed to the ends of the tie rods. The tie plate is part of the upper tie plate assembly and is secured to the fuel bundle by securing the entire upper tie plate assembly to the locking sleeves fixed to the tie rods. The assembly includes, in addition to the tie plate, locking nuts for engaging the locking sleeves, retaining sleeves to operably connect the locking nuts to themore » assembly, a spring biased reaction plate to restrain the locking nuts in the locked position and a means to facilitate the removal of the entire assembly as a unit from the fuel bundle.« less
Metallic hot wire anemometer. [for high speed wind tunnel tests
NASA Technical Reports Server (NTRS)
Lemos, F. R. (Inventor)
1977-01-01
A hot wire anemometer is described which has a body formed of heat resistant metal such as an alloy high in nickel content which supports a probe wire disposed in a V groove in the body. The V groove contains a high temperature ceramic adhesive that partially encompasses the downstream side of the probe wire. Mechanical and electrical connection to the probe wire is achieved through conductive support rods that are constructed of the same high temperature metal, insulation between the body and the conductor rods being provided by a coating of an oxide of the same material which coating is formed in situ. The oxide coating insulates the conductor rods from the body, mechanically fixes the conductors within the body, and maintains its integrity at elevated temperatures.
Probe with integrated heater and thermocouple pack
McCulloch, Reg W.; Dial, Ralph E.; Finnell, Wilber K. R.
1990-01-01
A probe for measuring heat includes an elongate rod fitted within a sheath, and a plurality of annular recesses are formed on the surface of the rod in a spaced-apart relationship to form annular chambers that are resistant to heat flow. A longitudinal bore extends axially into the rod and within the cylinders defined by the annular chambers, and an integrated heater and thermocouple pack is dimensioned to fit within the bore. In construction, the integrated pack includes a plurality of wires disposed in electrical insulation within a sheath and a heater cable. These wires include one common wire and a plurality of thermocuple wires. The common wire is constructed of one type of conductive material while the thermocouple wires are each constructed of two types of materials so that at least one thermocouple junction is formed therein. All of the wires extend the length of the integrated pack and are connected together at their ends. The thermocouple wires are constructed to form thermocouple junctions proximate to each annular chamber for producing electromotive forces corresponding to the temperature of the rod within the annular chambers relative to outside the chambers. In the preferred embodiment, each thermocouple wire forms two thermocouple junctions, one junction being disposed within an annular chamber and the second junction being disposed outside of, but proximate to, the same annular chamber. In one embodiment two thermocouple wires are configured to double the sensitivity of the probe in one region.
Probe with integrated heater and thermocouple pack
McCulloch, Reginald W.; Dial, Ralph E.; Finnell, Wilber K. R.
1988-01-01
A probe for measuring heat includes an elongate rod fitted within a sheath, and a plurality of annular recesses are formed on the surface of the rod in a spaced-apart relationship to form annular chambers that are resistant to heat flow. A longitudinal bore extends axially into the rod and within the cylinders defined by the annular chambers, and an integrated heater and thermocouple pack is dimensioned to fit within the bore. In construction, the integrated pack includes a plurality of wires disposed in electrical insulation within a sheath and a heater cable. These wires include one common wire and a plurality of thermocouple wires. The common wire is constructed of one type of conductive material while the thermocouple wires are each constructed of two types of materials so that at least one thermocouple junction is formed therein. All of the wires extend the length of the integrated pack and are connected together at their ends. The thermocouple wires are constructed to form thermocouple junctions proximate to each annular chamber for producing electromotive forces corresponding to the temperature of the rod within the annular chambers relative to outside the chambers. In the preferred embodiment, each thermocouple wire forms two thermocouple junctions, one junction being disposed within an annular chamber and the second junction being disposed outside of, but proximate to, the same annular chamber. In one embodiment two thermocouple wires are configured to double the sensitivity of the probe in one region.
Helbert, Anne-Laure; Moya, Alice; Jil, Tomas; Andrieux, Michel; Ignat, Michel; Brisset, François; Baudin, Thierry
2015-10-01
In this paper, the traceability of copper from the anode to the cathode and then the wire rod has been studied in terms of impurity content, microstructure, texture, recrystallization kinetics, and ductility. These characterizations were obtained based on secondary ion mass spectrometry, differential scanning calorimetry (DSC), X-ray diffraction, HV hardness, and electron backscattered diffraction. It is shown that the recrystallization was delayed by the total amount of impurities. From tensile tests performed on cold drawn and subsequently annealed wires for a given time, a simplified model has been developed to link tensile elongation to the chemical composition. This model allowed quantification of the contribution of some additional elements, present in small quantity, on the recrystallization kinetics. The proposed model adjusted for the cold-drawn wires was also validated on both the cathode and wire rod used for the study of traceability.
High frequency magnetostrictive transducers for waveguide applications
DOE Office of Scientific and Technical Information (OSTI.GOV)
Daw, Joshua Earl; Taylor, Steven Cheney; Rempe, Joy Lynn
A high frequency magnetostrictive transducer includes a magnetostrictive rod or wire inserted co-axially into a driving coil, wherein the driving coil includes a coil arrangement with a plurality of small coil segments along the magnetostrictive rod or wire; wherein frequency operation of the high frequency magnetostrictive transducer is controlled by a length of the small coil segments and a material type of the magnetostrictive rod or wire. This design of the high frequency magnetostrictive transducer retains the beneficial aspects of the magnetostrictive design, while reducing its primary drawback, lower frequency operation.
Wang, Sou-Tien
1994-11-01
A wire cable assembly (10, 310) adapted for the winding of electrical coils is taught. A primary intended use is for use in particle tube assemblies (532) for the superconducting super collider. The correction coil cables (10, 310) have wires (14, 314) collected in wire arrays (12, 312) with a center rib (16, 316) sandwiched therebetween to form a core assembly (18, 318 ). The core assembly (18, 318) is surrounded by an assembly housing (20, 320) having an inner spiral wrap (22, 322) and a counter wound outer spiral wrap (24, 324). An alternate embodiment (410) of the invention is rolled into a keystoned shape to improve radial alignment of the correction coil cable (410) on a particle tube (733) in a particle tube assembly (732).
Federal Register 2010, 2011, 2012, 2013, 2014
2011-05-11
... States Court of Appeals for the Federal Circuit (``CAFC'') in Timken Co. v. United States, 893 F.2d 337... calculation upon concluding that Rajratan produced wire rod, a material input in the production of subject... financial statements and found that Rajratan purchases wire rod, in addition to other raw materials, and...
NASA Technical Reports Server (NTRS)
Stephens, James B. (Inventor); Yang, Mary M. (Inventor); Laue, Eric G. (Inventor)
1985-01-01
A solid electrolytic type hygrometer is described, which operates with high reliability while providing rapid and sensitive response. A gold foil electrode (16) is wrapped about a hollow glass cylinder (18), a sheet (12) of hygroscopic-electrolytic material is wrapped about the foil, and a wire (14) is wound around the outside of the electrolytic sheet. Moisture passing between wire turns can be absorbed by the electrolytic material (12), and then dissociated by current passed by the electrodes (14, 16) through the electrolytic material. The cylinder has a slit (20) extending along its length, to allow resilient expansion to press the sheet of electrolytic material firmly against the electrodes. The wire turns lie against one another to cause rapid dissociation of moisture throughout the electrolytic material. Additional guard wires (42,44, FIG. 2) lie at opposite ends of the electrolytic sheet, and currents pass through them to avoid moisture buildup at the ends of the main wire coil. The electrical current through the sheet or membrane is proportional to the partial pressure of the water-vapor.
General correlation for prediction of critical heat flux ratio in water cooled channels
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pernica, R.; Cizek, J.
1995-09-01
The paper present the general empirical Critical Heat Flux Ration (CHFR) correlation which is valid for vertical water upflow through tubes, internally heated concentric annuli and rod bundles geometries with both wide and very tight square and triangular rods lattices. The proposed general PG correlation directly predicts the CHFR, it comprises axial and radial non-uniform heating, and is valid in a wider range of thermal hydraulic conditions than previously published critical heat flux correlations. The PG correlation has been developed using the critical heat flux Czech data bank which includes more than 9500 experimental data on tubes, 7600 data onmore » rod bundles and 713 data on internally heated concentric annuli. Accuracy of the CHFR prediction, statistically assessed by the constant dryout conditions approach, is characterized by the mean value nearing 1.00 and the standard deviation less than 0.06. Moverover, a subchannel form of the PG correlations is statistically verified on Westinghouse and Combustion Engineering rod bundle data bases, i.e. more than 7000 experimental CHF points of Columbia University data bank were used.« less
77 FR 74174 - North American Free Trade Agreement (NAFTA), Article 1904 Binational Panel Reviews
Federal Register 2010, 2011, 2012, 2013, 2014
2012-12-13
... Department of Commerce's Final Determination of Carbon and Certain Alloy Steel Wire Rod from Canada... concerning Carbon and Certain Alloy Steel Wire Rod from Canada. The Secretariat was instructed to issue a...
Shape-Memory Wires Switch Rotary Actuator
NASA Technical Reports Server (NTRS)
Brudnicki, Myron J.
1992-01-01
Thermomechanical rotary actuator based on shape-memory property of alloy composed of equal parts of titanium and nickel. If alloy stretched while below transition temperature, it reverts to original length when heated above transition temperature. Two capstans on same shaft wrapped with shape-memory wires. As one wire heated, it contracts and stretches opposite wire. Wires heated in alternation so they switch shaft between two extreme angular positions; "on" and "off" positions of rotary valve.
46 CFR 108.553 - Survival craft launching and recovery arrangements using falls and a winch.
Code of Federal Regulations, 2011 CFR
2011-10-01
...) Each fall wire must be of rotation-resistant and corrosion-resistant steel wire rope. (b) The breaking strength of each fall wire and each attachment used on the fall must be at least six times the load... levers. (e) Each winch drum must be arranged so the fall wire winds onto the drum in a level wrap, and a...
46 CFR 133.153 - Survival craft launching and recovery arrangements using falls and a winch.
Code of Federal Regulations, 2010 CFR
2010-10-01
...) Each fall wire must be of rotation-resistant and corrosion-resistant steel wire rope. (b) The breaking strength of each fall wire and each attachment used on the fall must be at least six times the load.... (e) Each winch drum must be arranged so the fall wire winds onto the drum in a level wrap. A multiple...
46 CFR 133.153 - Survival craft launching and recovery arrangements using falls and a winch.
Code of Federal Regulations, 2011 CFR
2011-10-01
...) Each fall wire must be of rotation-resistant and corrosion-resistant steel wire rope. (b) The breaking strength of each fall wire and each attachment used on the fall must be at least six times the load.... (e) Each winch drum must be arranged so the fall wire winds onto the drum in a level wrap. A multiple...
46 CFR 108.553 - Survival craft launching and recovery arrangements using falls and a winch.
Code of Federal Regulations, 2010 CFR
2010-10-01
...) Each fall wire must be of rotation-resistant and corrosion-resistant steel wire rope. (b) The breaking strength of each fall wire and each attachment used on the fall must be at least six times the load... levers. (e) Each winch drum must be arranged so the fall wire winds onto the drum in a level wrap, and a...
76 FR 62653 - Airworthiness Directives; Airbus Model A310 Series Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2011-10-11
... the fuel electrical circuit in the Right Hand (RH) wing must be modified in order to ensure better... 2S of the fuel electrical circuit in the Right Hand (RH) wing must be modified in order to ensure... the wire bundle 2S in the RH wing pylon area to the generator wire bundle of engine 2. The...
75 FR 74663 - Airworthiness Directives; The Boeing Company Model 747-400 and -400D Series Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2010-12-01
... number three engine pylons near the leading edge, and related investigative and corrective actions, if... routing of the wire bundles in the number two and number three engine pylons near the leading edge, and... routing of the wire bundles in the number two and number three engine pylons near the leading edge; and do...
Lightweight electrical connector split backshell
NASA Technical Reports Server (NTRS)
Goldman, Elliot (Inventor)
2009-01-01
An electrical connector split backshell is provided, comprising two substantially identical backshell halves. Each half includes a first side and a cam projecting therefrom along an axis perpendicular thereto, the cam having an alignment tooth with a constant radius and an engagement section with a radius that increases with angular distance from the alignment tooth. Each half further includes a second side parallel to the first side and a circular sector opening disposed in the second side, the circular sector opening including an inner surface configured as a ramp with a constant radius, the ramp being configured to engage with an engagement section of a cam of the other half, the circular sector opening further including a relieved pocket configured to receive an alignment tooth of the cam of the other half. Each half further includes a back side perpendicular to the first and second sides and a wire bundle notch disposed in the back side, the wire bundle notch configured to align with a wire bundle notch of the other half to form a wire bundle opening. The two substantially identical halves are rotatably coupled by engaging the engagement section of each half to the ramp of the other half.
Structure and Growth of Quasi One-Dimensional YSi2 Nanophases on Si(100)
Iancu, V.; Kent, P.R.C.; Hus, S.; Hu, H.; Zeng, C.G.; Weitering, H.H.
2013-01-01
Quasi one-dimensional YSi2 nanostructures are formed via self-assembly on the Si(100) surface. These epitaxial nanowires are metastable and their formation strongly depends on the growth parameters. Here, we explore the various stages of yttrium silicide formation over a range of metal coverages and growth temperatures, and establish a rudimentary phase diagram for these novel and often coexisting nanophases. In addition to previously identified stoichiometric wires, we identify several new nanowire systems. These nanowires exhibit a variety of surface reconstructions, which sometimes coexist on a single wire. From a comparison of scanning tunneling microcopy images, tunneling spectra, and first-principles density functional theory calculations, we determine that these surface reconstructions arise from local orderings of yttrium vacancies. Nanowires often agglomerate into nanowire bundles, the thinnest of which are formed by single wire pairs. The calculations show that such bundles are energetically favored compared to well-separated single wires. Thicker bundles are formed at slightly higher temperature. They extend over several microns, forming a robust network of conducting wires that could possibly be employed in nanodevice applications. PMID:23221350
Transporter for Treated Sheet Materials
NASA Technical Reports Server (NTRS)
Pollack, M., H.
1983-01-01
Plastic spacers keep parts separated during transport or storage. Cart with rods and spacers holds sheets with delicate finishes for storage or transport. Sheets supported vertically by rods, or horizontally. Spacers keep sheets separated. Designed to eliminate time and expense of tapping, wrapping, and sometimes refinishing aluminum sheets with delicate anodized finished.
Synthesis and magnetic properties of bundled and dispersed Co{sub 3}O{sub 4} nanowires
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhang, B.B.; Wang, P.F.; Xu, J.C.
Highlights: • Co{sub 3}O{sub 4} nanowires possessed the same diameter and the different interwires distance. • All samples possessed antiferromagnetism and superparamagnetism at high temperature. • The exchange bias effect was observed at low temperature. • The surface spin coupling restrained the surface effect of magnetic nanostructures. - Abstract: The magnetic Co{sub 3}O{sub 4} nanowires were synthesized using the templates of SBA-15, and then the well-dispersed nanowires (D-wires) were separated from the bundled ordered nanowires (B-wires) with the centrifugal technique. TEM images indicated that D-wires were highly dispersed Co{sub 3}O{sub 4} nanowires and B-wires existed in bundles. All samples possessedmore » the antiferromagnetism and superparamagnetism at high temperature. After revealing the intrinsic magnetic properties of Co{sub 3}O{sub 4} nanowires with D-wires, the magnetic behavior of B-wires was discussed in detail, and then the magnetic interaction between neighboring nanowires could be deduced. The exchange bias effect from the body Co{sub 3}O{sub 4} antiferromagnetism and surface ferromagnetism was observed at low temperature. The magnetization of B-wires was higher than that of D-wires, which was attributed to the constraint of the surface spin coupling between the neighboring nanowires to the surface affect of nanostructures.« less
Update on High-Temperature Coils for Electromagnets
NASA Technical Reports Server (NTRS)
Kascak, Albert F.; Montague, Gerald T.; Palazzolo, Alan; Preuss, Jason; Carter, Bart; Tucker, Randall; Hunt, Andrew
2005-01-01
A report revisits the subject matter of "High-Temperature Coils for Electromagnets" (LEW-17164), NASA Tech Briefs, Vol. 26, No. 8, (August 2002) page 38. To recapitulate: Wires have been developed for use in electromagnets that operate at high temperatures. The starting material for a wire of this type can be either a nickel-clad, ceramic-insulated copper wire or a bare silver wire. The wire is covered by electrical-insulation material that is intended to withstand operating temperatures in the range from 800 to 1,300 F (.430 to .700 C): The starting wire is either primarily wrapped with S-glass as an insulating material or else covered with another insulating material wrapped in S-glass prior to the winding process. A ceramic binding agent is applied as a slurry during the winding process to provide further insulating capability. The turns are pre-bent during winding to prevent damage to the insulation. The coil is then heated to convert the binder into ceramic. The instant report mostly reiterates the prior information and presents some additional information on the application of the ceramic binding agent and the incorporation of high-temperature wire into the windings.
NASA Astrophysics Data System (ADS)
Torres, V.; Quek, S.; Gaydecki, P.
2010-02-01
Aging and deterioration of the main functional parts in civil structures is one of the biggest problems that private and governmental institutions, dedicated to operate and maintain such structures, are facing now days. In the case of relatively old suspension bridges, problems emerge due to corrosion and break of wires in the main cables. Decisive information and a reliable monitoring and evaluation are factors of great relevance required to prevent significant or catastrophic damages caused to the structure, and more importantly, to people. The main challenge for the NDE methods of inspection arises in dealing with the steel wrapping barrier of the suspension cable, which main function is to shield, shape and hold the bundles. The following work, presents a study of a multi-Magnetoresistive sensors system aiming to support the monitoring and evaluation of suspension cables at some of its stages. Modelling, signal acquisition, signal processing, experiments and the initial phases of implementation are presented and discussed widely.
46 CFR 183.340 - Cable and wiring requirements.
Code of Federal Regulations, 2010 CFR
2010-10-01
... a manner as to avoid chafing and other damage. The use of plastic tie wraps must be limited to... requirements. (a) If individual wires, rather than cable, are used in systems greater than 50 volts, the wire... current carrying capacity for the circuit in which they are used; (2) Be installed in a manner to avoid or...
1984-03-01
surrounded the rat. The ends of the screen wire tube were twisted and secured with galvanized wire. Care was taken to wrap the screen wire tight so that...function. In N. R. DiLuzio and R. Paoletti (eds.). The reticuloendothelial system and atherosclerosis : Advances in experimental medicine and biology, pp
Correlating electronic transport to atomic structures in self-assembled quantum wires.
Qin, Shengyong; Kim, Tae-Hwan; Zhang, Yanning; Ouyang, Wenjie; Weitering, Hanno H; Shih, Chih-Kang; Baddorf, Arthur P; Wu, Ruqian; Li, An-Ping
2012-02-08
Quantum wires, as a smallest electronic conductor, are expected to be a fundamental component in all quantum architectures. The electronic conductance in quantum wires, however, is often dictated by structural instabilities and electron localization at the atomic scale. Here we report on the evolutions of electronic transport as a function of temperature and interwire coupling as the quantum wires of GdSi(2) are self-assembled on Si(100) wire-by-wire. The correlation between structure, electronic properties, and electronic transport are examined by combining nanotransport measurements, scanning tunneling microscopy, and density functional theory calculations. A metal-insulator transition is revealed in isolated nanowires, while a robust metallic state is obtained in wire bundles at low temperature. The atomic defects lead to electron localizations in isolated nanowire, and interwire coupling stabilizes the structure and promotes the metallic states in wire bundles. This illustrates how the conductance nature of a one-dimensional system can be dramatically modified by the environmental change on the atomic scale. © 2012 American Chemical Society
High strength, low carbon, dual phase steel rods and wires and process for making same
Thomas, Gareth; Nakagawa, Alvin H.
1986-01-01
A high strength, high ductility, low carbon, dual phase steel wire, bar or rod and process for making the same is provided. The steel wire, bar or rod is produced by cold drawing to the desired diameter in a single multipass operation a low carbon steel composition characterized by a duplex microstructure consisting essentially of a strong second phase dispersed in a soft ferrite matrix with a microstructure and morphology having sufficient cold formability to allow reductions in cross-sectional area of up to about 99.9%. Tensile strengths of at least 120 ksi to over 400 ksi may be obtained.
How should I treat a patient to remove a fractured jailed side branch wire?
Owens, Colum G; Spence, Mark S
2011-08-01
A 53-year-old female was sent for diagnostic angiography after successful reperfusion therapy for an anterior ST-elevation myocardial infarct. The culprit lesion was a LAD/D1 bifurcation stenosis. Coronary angiography, intravascular ultrasound. Left anterior descending artery/first diagonal artery bifurcation stenosis, fractured jailed side branch wire. Provisional stenting strategy for bifurcation stenosis. Consideration of surgical and percutaneous options to retrieve fractured, jailed, side branch wire. Wire and balloon catheter wrap technique for retrieval of fractured wire.
Large-break LOCA, in-reactor fuel bundle Materials Test MT-6A
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wilson, C.L.; Hesson, G.M.; Pilger, J.P.
1993-09-01
This is a report on one of a series of experiments to simulates a loss-of-coolant accident (LOCA) using full-length fuel rods for pressurized water reactors (PWR). The experiments were conducted by Pacific Northwest Laboratory (PNL) under the LOCA simulation Program sponsored by the US Nuclear Regulatory Commission (NRC). The major objective of this program was causing the maximum possible expansion of the cladding on the fuel rods from a short-term adiabatic temperature transient to 1200 K (1700 F) leading to the rupture of the cladding; and second, by reflooding the fuel rods to determine the rate at which the fuelmore » bundle is cooled.« less
40 CFR 420.96 - Pretreatment standards for new sources (PSNS).
Code of Federal Regulations, 2010 CFR
2010-07-01
...) EFFLUENT GUIDELINES AND STANDARDS IRON AND STEEL MANUFACTURING POINT SOURCE CATEGORY Acid Pickling...) Sulfuric acid pickling (spent acid solutions and rinse waters)—(1) Rod, wire, coil. Subpart I Pollutant or... operations. (b) Hydrochloric acid pickling (spent acid solutions and rinse waters)—(1) Rod, wire, coil...
40 CFR 420.95 - Pretreatment standards for existing sources (PSES).
Code of Federal Regulations, 2010 CFR
2010-07-01
...) EFFLUENT GUIDELINES AND STANDARDS IRON AND STEEL MANUFACTURING POINT SOURCE CATEGORY Acid Pickling... for existing sources. (a) Sulfuric acid (spent acid solutions and rinse waters)—(1) Rod, wire, and... pickling (spent acid solutions and rinse waters)—(1) Rod, wire, and coil. Subpart I Pollutant or pollutant...
Wrapping process for fabrication of A-15 superconducting composite wires
Suenaga, M.; Klamut, C.J.; Luhman, T.S.
1980-08-15
A method for fabricating superconducting wires wherein a billet of copper containing filaments of niobium or vanadium is rolled to form a strip which is wrapped about a tin-alloy core to form a composite. The alloy is a tin-copper alloy for niobium filaments and a gallium-copper alloy for vanadium filaments. The composite is then drawn down to a desired wire size and heat treated. During the heat treatment process, the tin in the bronze reacts with the niobium to form the superconductor niobium tin. In the case where vanadium is used, the gallium in the gallium bronze reacts with the vanadium to form the superconductor vanadium gallium. This new process eliminates the costly annealing steps, external tin plating and drilling of bronze ingots required in a number of prior art processes.
NASA Astrophysics Data System (ADS)
Koopman, D. A.; Paul, C. R.
1984-08-01
Electrical devices (computers, radar systems, communication radios, etc.) are interconnected by wires on most present systems. Electromagnetic fields produced by the excitation of these wires will cause unintentional coupling of signals onto nearby wires. This undesired electromagnetic coupling is termed crosstalk. It is important to be able to determine whether these crosstalk signals will cause the devices at the ends of the wires to malfunction. Wires are often grouped together in cable bundles or harnesses. The close proximity of wires in these bundles enhances the possibility that the crosstalk levels will be sufficiently large to cause malfunctions. The ability to predict crosstalk levels and the means to control crosstalk when it causes a problem are important to optimum system design. It interference of this type is allowed to surface during final system tests, a costly and time consuming retrofit of the wiring or the addition of filters and other interference control measures may be required.
Landing Gear Components Noise Study - PIV and Hot-Wire Measurements
NASA Technical Reports Server (NTRS)
Hutcheson, Florence V.; Burley, Casey L.; Stead, Daniel J.; Becker, Lawrence E.; Price, Jennifer L.
2010-01-01
PIV and hot-wire measurements of the wake flow from rods and bars are presented. The test models include rods of different diameters and cross sections and a rod juxtaposed to a plate. The latter is representative of the latch door that is attached to an aircraft landing gear when the gear is deployed, while the single and multiple rod configurations tested are representative of some of the various struts and cables configuration present on an aircraft landing gear. The test set up is described and the flow measurements are presented. The effect of model surface treatment and freestream turbulence on the spanwise coherence of the vortex shedding is studied for several rod and bar configurations.
Correlation of Mechanical Properties with Diameter and Cooling Rate of 1080 Wire-Rod
NASA Astrophysics Data System (ADS)
Kohli, A.; Poirier, D. R.
2017-12-01
More than 540 heats of 1080 wire-rod were statistically analyzed by regression analyses to see whether tensile strength and percent reduction in area (%RA) relate to wire-rod diameter and composition. As diameter increases from 5.6 to 12.7 mm, the trend in %RA shows a decrease with negligible effect on the trend of the tensile strength. It was found that the estimated cooling rate at 700 °C during controlled cooling is responsible for the "diameter effect." The effect of composition on %RA is minor when contrasted to the "diameter effect." In particular, the effect of the concentrations of the residual elements on %RA within the compositional range studied is negligible.
Impedance of curved rectangular spiral coils around a conductive cylinder
NASA Astrophysics Data System (ADS)
Burke, S. K.; Ditchburn, R. J.; Theodoulidis, T. P.
2008-07-01
Eddy-current induction due to a thin conformable coil wrapped around a long conductive cylinder is examined using a second-order vector potential formalism. Compact closed-form expressions are derived for the self- and mutual impedances of curved rectangular spiral coils (i) in free space and (ii) when wrapped around the surface of the cylindrical rod. The validity of these expressions was tested against the results of a systematic series of experiments using a cylindrical Al-alloy rod and conformable coils manufactured using flexible printed-circuit-board technology. The theoretical expressions were in very good agreement with the experimental measurements. The significance of the results for eddy-current nondestructive inspection using flexible coils and flexible coil arrays is discussed.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-11-29
... binders board, a spine strip, and cover wrap). Subject merchandise may or may not contain any combination... strip, and cover wrap; newspapers; pictures and photographs; desk and wall calendars and organizers... spiral, or helical, wire and with plastic front and rear covers made of a blended polyolefin plastic...
Heat transfer in laminar flow along circular rods in infinite square arrays
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kim, J.H.; Li, W.H.
1988-02-01
The need to understand heat transfer characteristics over rods or tube bundles often arises in the design of compact heat exchangers and safety analysis of nuclear reactors. In particular, the fuel bundles of typical light water nuclear reactors are composed of a large number of circular rods arranged in square array pattern. The purpose of the present study is to analyze heat transfer characteristics of flow in such a multirod geometric configuration. The analysis given here will follow as closely as possible the method of Sparrow et al. who analyzed a similar problem for circular cylinders arranged in an equilateralmore » triangular array. The following major assumptions are made in the present analysis: (1) Flow is fully developed laminar flow paralleled to the axis of rods. (2) The axial profile of the surface heat flux to the fluid is uniform.(3) Thermodynamic properties are assumed constant.« less
[The effects of different welding wires on the mechanical properties of laser welding joints].
Huang, Qing-feng; Zhang, Jian-zhong; Jiang, Wei-dong; Li, Quan; Yu, Jin-xing
2006-08-01
To evaluate the mechanical properties and microstructure of laser-welded joints with different welding wires for clinical use of welding wire. The standard tensile test and three-point bending test rods were made from Co-Cr and Ni-Cr alloy, and were laser-welded with different welding wire (commercially welding wire and casting wire). Then the tensile rods were tested for the ultimate tensile strength (UTS), and the bending rods for the ultimate bending strength (UBS). The results was analyzed by one-way ANOVA. The tensile fracture surface were examined by scanning electron microscopy (SEM). Metallurgical analysis were also performed on polished longitudinal sectioned samples. For Co-Cr alloy, the UTS of casting wire group and commercially welding wire group was respectively (606.40+/-82.53)MPa and (693.61+/-47.68)MPa; the UBS was respectively (997.95+/-88.89)MPa and (1160.76+/-91.59)MPa. ANOVA showed a significant difference of UTS and UBS between the two groups at the 0.05 level (P<0.05). For Ni-Cr alloy, the UTS of casting wire group and commercially welding wire group was respectively (558.14+/-46.75)MPa and (582.32+/-35.43)MPa; the UBS was respectively (1084.75+/-46.02)MPa and (1078.29+/-36.25)MPa. There was no significant difference between the two groups (P>0.05). SEM and metallurgical examination showed the welded zone exhibiting more cracks in the casting wire group than in the commercially welding wire group. It would be advisable to work with commercially welding wire for the joints that need better strength.
NASA Technical Reports Server (NTRS)
Casey, E. J.; Commadore, C. C.; Ingles, M. E.
1980-01-01
Long wire bundles twist into uniform spiral harnesses with help of simple apparatus. Wires pass through spacers and through hand-held tool with hole for each wire. Ends are attached to low speed bench motor. As motor turns, operator moves hand tool away forming smooth twists in wires between motor and tool. Technique produces harnesses that generate less radio-frequency interference than do irregularly twisted cables.
Misra, A; Burke, JF; Ramayya, A; Jacobs, J; Sperling, MR; Moxon, KA; Kahana, MJ; Evans, JJ; Sharan, AD
2014-01-01
Objective The authors report methods developed for the implantation of micro-wire bundles into mesial temporal lobe structures and subsequent single neuron recording in epileptic patients undergoing in-patient diagnostic monitoring. This is done with the intention of lowering the perceived barriers to routine single neuron recording from deep brain structures in the clinical setting. Approach Over a 15 month period, 11 patients were implanted with platinum micro-wire bundles into mesial temporal structures. Protocols were developed for A) monitoring electrode integrity through impedance testing, B) ensuring continuous 24-7 recording, C) localizing micro-wire position and “splay” pattern and D) monitoring grounding and referencing to maintain the quality of recordings. Main Result Five common modes of failure were identified: 1) broken micro-wires from acute tensile force, 2) broken micro-wires from cyclic fatigue at stress points, 3) poor in-vivo micro-electrode separation, 4) motion artifact and 5) deteriorating ground connection and subsequent drop in common mode noise rejection. Single neurons have been observed up to 14 days post implantation and on 40% of micro-wires. Significance Long-term success requires detailed review of each implant by both the clinical and research teams to identify failure modes, and appropriate refinement of techniques while moving forward. This approach leads to reliable unit recordings without prolonging operative times, which will help increase the availability and clinical viability of human single neuron data. PMID:24608589
An effective model of DNA like helicoidal structure: with length fluctuation nonlinearity
NASA Astrophysics Data System (ADS)
Tseytlin, Y. M.
2011-03-01
One of the natural helicoidal nanostructure, which thermomechanical features are studied carefully with the help of different mechanical models, is a DNA cell / molecule. Our study proves that the experimentally determined nonlinear fluctuations of the molecular length of DNA can be better understood by modeling the molecule as a helicoidal pretwisted nanostrip sensor with nonlinear function. The calculations presented here are in good agreement with the experimental data within 10%. Other used by many researchers mechanical models such as an elastic rod, wormlike chain (WLC), accordion bellows, or an elastic core wrapped with rigid wires do not show the possible variance nonlinearity of thermomechanical DNA molecular length fluctuations. We have found that the nonlinear variance of the length fluctuations is an intrinsic property of the micro-nano-sensors with helicoidal shape. This model allows us to estimate the persistence length and twist-stretch coupling of a DNA molecule as well. It also shows the molecule's overwinding possibility at initial stretching with correct numerical representation.
1982-02-01
facilitant la transition entre les plans d’ing~nierie 6lectronique et la matrice pertinente d’interconnexions requise pour le montage par c~blage enroul6 Wire...Wrap. Le d~veloppement de prototypes 6lectroniques s’est vu consid6rablement acc6l6r6 par la preparation plus rapide des donn~es d’interconnexions...directory, all located in *APL files (Sect. 7.0). A matrix called BANQUE is also formed by the program L to regroup those chip descriptions of the main
Large-eddy simulations of turbulent flow for grid-to-rod fretting in nuclear reactors
Bakosi, J.; Christon, M. A.; Lowrie, R. B.; ...
2013-07-12
The grid-to-rod fretting (GTRF) problem in pressurized water reactors is a flow-induced vibration problem that results in wear and failure of the fuel rods in nuclear assemblies. In order to understand the fluid dynamics of GTRF and to build an archival database of turbulence statistics for various configurations, implicit large-eddy simulations of time-dependent single-phase turbulent flow have been performed in 3 × 3 and 5 × 5 rod bundles with a single grid spacer. To assess the computational mesh and resolution requirements, a method for quantitative assessment of unstructured meshes with no-slip walls is described. The calculations have been carriedmore » out using Hydra-TH, a thermal-hydraulics code developed at Los Alamos for the Consortium for Advanced Simulation of Light water reactors, a United States Department of Energy Innovation Hub. Hydra-TH uses a second-order implicit incremental projection method to solve the singlephase incompressible Navier-Stokes equations. The simulations explicitly resolve the large scale motions of the turbulent flow field using first principles and rely on a monotonicity-preserving numerical technique to represent the unresolved scales. Each series of simulations for the 3 × 3 and 5 × 5 rod-bundle geometries is an analysis of the flow field statistics combined with a mesh-refinement study and validation with available experimental data. Our primary focus is the time history and statistics of the forces loading the fuel rods. These hydrodynamic forces are believed to be the key player resulting in rod vibration and GTRF wear, one of the leading causes for leaking nuclear fuel which costs power utilities millions of dollars in preventive measures. As a result, we demonstrate that implicit large-eddy simulation of rod-bundle flows is a viable way to calculate the excitation forces for the GTRF problem.« less
Evaluation Of Risk And Possible Mitigation Schemes For Previously Unidentified Hazards
NASA Technical Reports Server (NTRS)
Linzey, William; McCutchan, Micah; Traskos, Michael; Gilbrech, Richard; Cherney, Robert; Slenski, George; Thomas, Walter, III
2006-01-01
This report presents the results of arc track testing conducted to determine if such a transfer of power to un-energized wires is possible and/or likely during an arcing event, and to evaluate an array of protection schemes that may significantly reduce the possibility of such a transfer. The results of these experiments may be useful for determining the level of protection necessary to guard against spurious voltage and current being applied to safety critical circuits. It was not the purpose of these experiments to determine the probability of the initiation of an arc track event only if an initiation did occur could it cause the undesired event: an inadvertent thruster firing. The primary wire insulation used in the Orbiter is aromatic polyimide, or Kapton , a construction known to arc track under certain conditions [3]. Previous Boeing testing has shown that arc tracks can initiate in aromatic polyimide insulated 28 volts direct current (VDC) power circuits using more realistic techniques such as chafing with an aluminum blade (simulating the corner of an avionics box or lip of a wire tray), or vibration of an aluminum plate against a wire bundle [4]. Therefore, an arc initiation technique was chosen that provided a reliable and consistent technique of starting the arc and not a realistic simulation of a scenario on the vehicle. Once an arc is initiated, the current, power and propagation characteristics of the arc depend on the power source, wire gauge and insulation type, circuit protection and series resistance rather than type of initiation. The initiation method employed for these tests was applying an oil and graphite mixture to the ends of a powered twisted pair wire. The flight configuration of the heater circuits, the fuel/oxider (or ox) wire, and the RCS jet solenoid were modeled in the test configuration so that the behavior of these components during an arcing event could be studied. To determine if coil activation would occur with various protection wire schemes, 145 tests were conducted using various fuel/ox wire alternatives (shielded and unshielded) and/or different combinations of polytetrafuloroethylene (PTFE), Mystik tape and convoluted wraps to prevent unwanted coil activation. Test results were evaluated along with other pertinent data and information to develop a mitigation strategy for an inadvertent RCS firing. The SSP evaluated civilian aircraft wiring failures to search for aging trends in assessing the wire-short hazard. Appendix 2 applies Weibull statistical methods to the same data with a similar purpose.
Dielectric Heaters for Testing Spacecraft Nuclear Reactors
NASA Technical Reports Server (NTRS)
Sims, William Herbert; Bitteker, Leo; Godfroy, Thomas
2006-01-01
A document proposes the development of radio-frequency-(RF)-driven dielectric heaters for non-nuclear thermal testing of the cores of nuclear-fission reactors for spacecraft. Like the electrical-resistance heaters used heretofore for such testing, the dielectric heaters would be inserted in the reactors in place of nuclear fuel rods. A typical heater according to the proposal would consist of a rod of lossy dielectric material sized and shaped like a fuel rod and containing an electrically conductive rod along its center line. Exploiting the dielectric loss mechanism that is usually considered a nuisance in other applications, an RF signal, typically at a frequency .50 MHz and an amplitude between 2 and 5 kV, would be applied to the central conductor to heat the dielectric material. The main advantage of the proposal is that the wiring needed for the RF dielectric heating would be simpler and easier to fabricate than is the wiring needed for resistance heating. In some applications, it might be possible to eliminate all heater wiring and, instead, beam the RF heating power into the dielectric rods from external antennas.
Sulfur Content Precision Control Technology for CO2-Shielded Welding Wire Steel
NASA Astrophysics Data System (ADS)
Chaofa, Zhang; Huaqiang, Hao; Youbing, Xiang; Shanxi, Liu
As a kind of impurity and displaying with FeS and MnS form in steel, Sulfur can make the disadvantage effect on the performance of hot-working, welding and corrosion resistance. The high content sulfur in steel can cause the hot brittle phenomenon for the steel. For the welding steel, when the sulfur content is higher, the drawing performance of wire rod become worst and the yield of wire rod decrease. When the sulfur is lower, the automatic wire feeding performance for the gas shielded welding become worst and the weld seam is not smooth. According to the results of welding expert research, 0.010%≤ S≤ 0.020% in CO2-shielded welding wire steel is reasonable.
Crossflow between subchannels in a 5 x 5 rod-bundle geometry
NASA Astrophysics Data System (ADS)
Lee, Jungjin; Park, Hyungmin
2017-11-01
In the present study, we experimentally investigate the single-phase (water as a working fluid) flow in a vertical 5 x 5 rod-bundle geometry using a particle image velociemtry, especially focusing on the crossflow phenomena between subchannels. This crossflow phenomena is very important in determining the performance and safety of nuclear power plant. To measure the flow behind the rod, it is made of FEP (Fluorinated Ethylene Propylene) to achieve the index matching. The ratio of pitch between rods and rod diameter is 1.4, and the considered Reynolds number based on a hydraulic diameter of a channel and an axial bulk velocity is 10000. Also, the typical grid spacer is installed periodically along the streamwise direction. Depending on the location of subchannel (e.g., distance to the side wall or grid spacer), the flow (turbulence) statistics show large variations that will be discussed in detail. Furthermore, we will suggest a modified crossflow model that can explain the varying crossflow phenomena more clearly. Supported by NRF Grant (NRF-2016M2B2A9A02945068) of the Korean government.
Detail of conning tower atop the submarine. Note the wire ...
Detail of conning tower atop the submarine. Note the wire rope wrapped around the base of the tower, which may have been used in an attempt to pull the submarine offshore. - Sub Marine Explorer, Located along the beach of Isla San Telmo, Pearl Islands, Isla San Telmo, Former Panama Canal Zone, CZ
Characterization and Fate of Gun and Rocket Propellant Residues on Testing and Training Ranges
2011-08-01
propellant sticks, is tied in three places with polyester and cotton thread ties. The bundle is then wrapped in lead foil (a de-coppering agent...sticks and the tying of the bundle in five places, again using polyester and cotton thread ties. The combustible case is manufactured mainly from...and brought back to DRDC to be weighed and extracted to measure the remaining 2,4-DNT. Most of what was collected was the remains of the cotton
Mechanized Polishing of Optical Rod and Fiber Ends
NASA Technical Reports Server (NTRS)
Gum, J. S.
1987-01-01
Workpiece holder for standard grinding and polishing machine makes it easier to produce optical finish and shape on end of metal or glass rod or bundle of optical fibers. Previously, glass parts lapped and polished manually, time-consuming procedure calling for considerable skill.
Loving, Vilert A; Edwards, David B; Roche, Kevin T; Steele, Joseph R; Sapareto, Stephen A; Byrum, Stephanie C; Schomer, Donald F
2014-06-01
In breast-conserving surgery for nonpalpable breast cancers, surgical reexcision rates are lower with radioactive seed localization (RSL) than wire localization. We evaluated the cost-benefit of switching from wire localization to RSL in two competing payment systems: a fee-for-service (FFS) system and a bundled payment system, which is typical for accountable care organizations. A Monte Carlo simulation was developed to compare the cost-benefit of RSL and wire localization. Equipment utilization, procedural workflows, and regulatory overhead differentiate the cost between RSL and wire localization. To define a distribution of possible cost scenarios, the simulation randomly varied cost drivers within fixed ranges determined by hospital data, published literature, and expert input. Each scenario was replicated 1000 times using the pseudorandom number generator within Microsoft Excel, and results were analyzed for convergence. In a bundled payment system, RSL reduced total health care cost per patient relative to wire localization by an average of $115, translating into increased facility margin. In an FFS system, RSL reduced total health care cost per patient relative to wire localization by an average of $595 but resulted in decreased facility margin because of fewer surgeries. In a bundled payment system, RSL results in a modest reduction of cost per patient over wire localization and slightly increased margin. A fee-for-service system suffers moderate loss of revenue per patient with RSL, largely due to lower reexcision rates. The fee-for-service system creates a significant financial disincentive for providers to use RSL, although it improves clinical outcomes and reduces total health care costs.
Application of the SHARP Toolkit to Sodium-Cooled Fast Reactor Challenge Problems
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shemon, E. R.; Yu, Y.; Kim, T. K.
The Simulation-based High-efficiency Advanced Reactor Prototyping (SHARP) toolkit is under development by the Nuclear Energy Advanced Modeling and Simulation (NEAMS) Campaign of the U.S. Department of Energy, Office of Nuclear Energy. To better understand and exploit the benefits of advanced modeling simulations, the NEAMS Campaign initiated the “Sodium-Cooled Fast Reactor (SFR) Challenge Problems” task, which include the assessment of hot channel factors (HCFs) and the demonstration of zooming capability using the SHARP toolkit. If both challenge problems are resolved through advanced modeling and simulation using the SHARP toolkit, the economic competitiveness of a SFR can be significantly improved. The effortsmore » in the first year of this project focused on the development of computational models, meshes, and coupling procedures for multi-physics calculations using the neutronics (PROTEUS) and thermal-hydraulic (Nek5000) components of the SHARP toolkit, as well as demonstration of the HCF calculation capability for the 100 MWe Advanced Fast Reactor (AFR-100) design. Testing the feasibility of the SHARP zooming capability is planned in FY 2018. The HCFs developed for the earlier SFRs (FFTF, CRBR, and EBR-II) were reviewed, and a subset of these were identified as potential candidates for reduction or elimination through high-fidelity simulations. A one-way offline coupling method was used to evaluate the HCFs where the neutronics solver PROTEUS computes the power profile based on an assumed temperature, and the computational fluid dynamics solver Nek5000 evaluates the peak temperatures using the neutronics power profile. If the initial temperature profile used in the neutronics calculation is reasonably accurate, the one-way offline method is valid because the neutronics power profile has weak dependence on small temperature variation. In order to get more precise results, the proper temperature profile for initial neutronics calculations was obtained from the STAR-CCM+ calculations. The HCFs of the peak temperatures at cladding outer surface, cladding inner wall surface, and fuel centerline induced by cladding manufacturing tolerance and uncertainties on the cladding, coolant, and fuel properties were evaluated for the AFR-100. Some assessment on the effect of wire wrap configuration and size of the bundle shows that it is practical to use the 7-pin bare rod bundle to calculate the HCFs. The resulting HCFs obtained from the high-fidelity SHARP calculations are generally smaller than those developed for the earlier SFRs because the most uncertainties involved in the modeling and simulations were disappeared. For completeness, additional investigations are planned in FY 2018, which will use random sampling techniques.« less
77 FR 9518 - Airworthiness Directives; The Boeing Company Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2012-02-17
...) Installation of New Relay and Wiring Bundle Within 72 months after the effective date of this AD: Change the... and temperature control system (CACTCS). This AD requires doing certain wiring changes, installing a new relay and necessary wiring in the CACTCS, and performing an operational test of the cooling pack...
One hundred angstrom niobium wire
NASA Technical Reports Server (NTRS)
Cline, H. E.; Rose, R. M.; Wulff, J.
1968-01-01
Composite of fine niobium wires in copper is used to study the size and proximity effects of a superconductor in a normal matrix. The niobium rod was drawn to a 100 angstrom diameter wire on a copper tubing.
Solar Power Wires Based on Organic Photovoltaic Materials
NASA Astrophysics Data System (ADS)
Lee, Michael R.; Eckert, Robert D.; Forberich, Karen; Dennler, Gilles; Brabec, Christoph J.; Gaudiana, Russell A.
2009-04-01
Organic photovoltaics in a flexible wire format has potential advantages that are described in this paper. A wire format requires long-distance transport of current that can be achieved only with conventional metals, thus eliminating the use of transparent oxide semiconductors. A phase-separated, photovoltaic layer, comprising a conducting polymer and a fullerene derivative, is coated onto a thin metal wire. A second wire, coated with a silver film, serving as the counter electrode, is wrapped around the first wire. Both wires are encased in a transparent polymer cladding. Incident light is focused by the cladding onto to the photovoltaic layer even when it is completely shadowed by the counter electrode. Efficiency values of the wires range from 2.79% to 3.27%.
Experimental study of burnout in channels with twisted fuel rods
NASA Astrophysics Data System (ADS)
Bol'Shakov, V. V.; Bashkirtsev, S. M.; Kobzar', L. L.; Morozov, A. G.
2007-05-01
The results of experimental studies of pressure drop and critical heat flux in the models of fuel assemblies (FAs) with fuel rod simulators twisted relative to the longitudinal axis and a three-ray cross section are considered. The experimental data are compared to the results obtained with the use of techniques adopted for design calculations with fuel rod bundles of type-VVER reactors.
Method of preparing composite superconducting wire
Verhoeven, John D.; Gibson, Edwin D.; Finnemore, Douglas K.; Ostenson, Jerome E.; Schmidt, Frederick A.; Owen, Charles V.
1985-08-06
An improved method of preparing composite multifilament superconducting wire of Nb.sub.3 Sn in a copper matrix which eliminates the necessity of coating the drawn wire with tin. A generalized cylindrical billet of an alloy of copper containing at least 15 weight percent niobium, present in the copper as discrete, randomly distributed and oriented dendritic-shaped particles, is provided with at least one longitudinal opening which is filled with tin to form a composite drawing rod. The drawing rod is then drawn to form a ductile composite multifilament wire containing a filament of tin. The ductile wire containing the tin can then be wound into magnet coils or other devices before heating to diffuse the tin through the wire to react with the niobium forming Nb.sub.3 Sn. Also described is an improved method for making large billets of the copper-niobium alloy by consumable-arc casting.
Improved method of preparing composite superconducting wire
Verhoeven, J.D.; Gibson, E.D.; Finnemore, D.K.; Ostenson, J.E.; Schmidt, F.A.; Owen, C.V.
1979-10-17
An improved method of preparing composite multifilament superconducting wire of Nb/sub 3/Sn in a copper matrix eliminates the necessity of coating the drawn wire with tin. A generalized cylindrical billet of an alloy of copper containing at least 15 weight percent niobium, present in the copper as discrete, randomly distributed and oriented dendritic-shaped particles, is provided with at least one longitudinal opening which is filled with tin to form a composite drawing rod. The drawing rod is then drawn to form a ductile composite multifilament wire containing a filament of tin. The ductile wire containing the tin can then be wound into magnet coils or other devices before heating to diffuse the tin through the wire to react with the niobium forming Nb/sub 3/Sn. Also described is an improved method for making large billets of the copper-niobium alloy by consumable-arc casting.
78 FR 16198 - Airworthiness Directives; The Boeing Company Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2013-03-14
... determine if wires touch the upper surface of the center upper auxiliary fuel tank, and marking the location, as necessary; inspecting all wire bundles above the center upper auxiliary fuel tank for splices and... requires inspecting to determine if wires touch the upper surface of the center upper auxiliary fuel tank...
78 FR 4055 - Airworthiness Directives; The Boeing Company Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2013-01-18
...) Installation of New Relay and Wiring Bundle Change Within 24 months after the effective date of this AD: Change... requires installing a new relay and doing certain wiring changes of the entertainment control switch. We... proposed to require installing a new relay and doing certain wiring changes of the entertainment control...
Thermoelectric device with multiple, nanometer scale, elements
NASA Technical Reports Server (NTRS)
Fleurial, Jean-Pierre (Inventor); Ryan, Margaret A. (Inventor); Borshchevsky, Alexander (Inventor); Herman, Jennifer (Inventor)
2006-01-01
A thermoelectric device formed of nanowires on the nm scale. The nanowires are preferably of a size that causes quantum confinement effects within the wires. The wires are connected together into a bundle to increase the power density.
Calculation of Heat-Bearing Agent’s Steady Flow in Fuel Bundle
NASA Astrophysics Data System (ADS)
Amosova, E. V.; Guba, G. G.
2017-11-01
This paper introduces the result of studying the heat exchange in the fuel bundle of the nuclear reactor’s fuel magazine. The article considers the fuel bundle of the infinite number of fuel elements, fuel elements are considered in the checkerboard fashion (at the tops of a regular triangle a fuel element is a plain round rod. The inhomogeneity of volume energy release in the rod forms the inhomogeneity of temperature and velocity fields, and pressure. Computational methods for studying hydrodynamics in magazines and cores with rod-shape fuel elements are based on a significant simplification of the problem: using basic (averaged) equations, isobaric section hypothesis, porous body model, etc. This could be explained by the complexity of math description of the three-dimensional fluid flow in the multi-connected area with the transfer coefficient anisotropy, curved boundaries and technical computation difficulties. Thus, calculative studying suggests itself as promising and important. There was developed a method for calculating the heat-mass exchange processes of inter-channel fuel element motions, which allows considering the contribution of natural convection to the heat-mass exchange based on the Navier-Stokes equations and Boussinesq approximation.
Saunders, Keith; Lomonossoff, George P
2017-01-01
We have utilized plant-based transient expression to produce tobacco mosaic virus (TMV)-based nano-rods of predetermined lengths. This is achieved by expressing RNAs containing the TMV origin of assembly sequence (OAS) and the sequence of the TMV coat protein either on the same RNA molecule or on two separate constructs. We show that the length of the resulting nano-rods is dependent upon the length of the RNA that possesses the OAS element. By expressing a version of the TMV coat protein that incorporates a metal-binding peptide at its C-terminus in the presence of RNA containing the OAS we have been able to produce nano-rods of predetermined length that are coated with cobalt-platinum. These nano-rods have the properties of defined-length nano-wires that make them ideal for many developing bionanotechnological processes.
Saunders, Keith; Lomonossoff, George P.
2017-01-01
We have utilized plant-based transient expression to produce tobacco mosaic virus (TMV)-based nano-rods of predetermined lengths. This is achieved by expressing RNAs containing the TMV origin of assembly sequence (OAS) and the sequence of the TMV coat protein either on the same RNA molecule or on two separate constructs. We show that the length of the resulting nano-rods is dependent upon the length of the RNA that possesses the OAS element. By expressing a version of the TMV coat protein that incorporates a metal-binding peptide at its C-terminus in the presence of RNA containing the OAS we have been able to produce nano-rods of predetermined length that are coated with cobalt-platinum. These nano-rods have the properties of defined-length nano-wires that make them ideal for many developing bionanotechnological processes. PMID:28878782
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mullins, C. B.; Felde, D. K.; Sutton, A. G.
1982-04-01
Reduced instrument responses are presented for Thermal-Hydraulic Test Facility (THTF) Test 3.03.6AR. This test was conducted by members of the ORNL Pressurized-Water-Reactor (PWR) Blowdown Heat Transfer (BDHT) Separate-Effects Program on May 21, 1980. Objective was to investigate heat transfer phenomena believed to occur in PWRs during accidents, including small and large break loss-of-coolant accidents. Test 3.03.6AR was conducted to obtain transient film boiling data in rod bundle geometry under reactor accident-type conditions. The primary purpose of this report is to make the reduced instrument responses for THTF Test 3.03.6AR available. Included in the report are uncertainties in the instrument responses,more » calculated mass flows, and calculated rod powers.« less
The mechanical response of talin
NASA Astrophysics Data System (ADS)
Yao, Mingxi; Goult, Benjamin T.; Klapholz, Benjamin; Hu, Xian; Toseland, Christopher P.; Guo, Yingjian; Cong, Peiwen; Sheetz, Michael P.; Yan, Jie
2016-07-01
Talin, a force-bearing cytoplasmic adapter essential for integrin-mediated cell adhesion, links the actin cytoskeleton to integrin-based cell-extracellular matrix adhesions at the plasma membrane. Its C-terminal rod domain, which contains 13 helical bundles, plays important roles in mechanosensing during cell adhesion and spreading. However, how the structural stability and transition kinetics of the 13 helical bundles of talin are utilized in the diverse talin-dependent mechanosensing processes remains poorly understood. Here we report the force-dependent unfolding and refolding kinetics of all talin rod domains. Using experimentally determined kinetics parameters, we determined the dynamics of force fluctuation during stretching of talin under physiologically relevant pulling speeds and experimentally measured extension fluctuation trajectories. Our results reveal that force-dependent stochastic unfolding and refolding of talin rod domains make talin a very effective force buffer that sets a physiological force range of only a few pNs in the talin-mediated force transmission pathway.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ninokata, H.; Deguchi, A.; Kawahara, A.
1995-09-01
A new void drift model for the subchannel analysis method is presented for the thermohydraulics calculation of two-phase flows in rod bundles where the flow model uses a two-fluid formulation for the conservation of mass, momentum and energy. A void drift model is constructed based on the experimental data obtained in a geometrically simple inter-connected two circular channel test sections using air-water as working fluids. The void drift force is assumed to be an origin of void drift velocity components of the two-phase cross-flow in a gap area between two adjacent rods and to overcome the momentum exchanges at themore » phase interface and wall-fluid interface. This void drift force is implemented in the cross flow momentum equations. Computational results have been successfully compared to experimental data available including 3x3 rod bundle data.« less
NASA Astrophysics Data System (ADS)
Kondo, Yoshiyuki; Suga, Keishi; Hibi, Koki; Okazaki, Toshihiko; Komeno, Toshihiro; Kunugi, Tomoaki; Serizawa, Akimi; Yoneda, Kimitoshi; Arai, Takahiro
2009-02-01
An advanced experimental technique has been developed to simulate two-phase flow behavior in a light water reactor (LWR). The technique applies three kinds of methods; (1) use of sulfur-hexafluoride (SF6) gas and ethanol (C2H5OH) liquid at atmospheric temperature and a pressure less than 1.0MPa, where the fluid properties are similar to steam-water ones in the LWR, (2) generation of bubble with a sintering tube, which simulates bubble generation on heated surface in the LWR, (3) measurement of detailed bubble distribution data with a bi-optical probe (BOP), (4) and measurement of liquid velocities with the tracer liquid. This experimental technique provides easy visualization of flows by using a large scale experimental apparatus, which gives three-dimensional flows, and measurement of detailed spatial distributions of two-phase flow. With this technique, we have carried out experiments simulating two-phase flow behavior in a single-channel geometry, a multi-rod-bundle one, and a horizontal-tube-bundle one on a typical natural circulation reactor system. Those experiments have clarified a) a flow regime map in a rod bundle on the transient region between bubbly and churn flow, b) three-dimensional flow behaviour in rod-bundles where inter-subassembly cross-flow occurs, c) bubble-separation behavior with consideration of reactor internal structures. The data have given analysis models for the natural circulation reactor design with good extrapolation.
The National Shipbuilding Research Program. Shipyard Welding Emission Factor Development
1999-09-01
percent composition in the rod/wire. Three specific HAPs of concern were identified: 1. Chrome and chromium compounds; 2. Nickel and nickel compounds...welding processes. These are: 1. Those rod/wires reported to be used in the largest amounts (> 10,000 pounds annually) did not contain chromium or...amounts ranging from less than 1,000 to greater than 10,000 pounds annually contained chromium and chromium compounds in concentrations ranging from
Saludes-Rodil, Sergio; Baeyens, Enrique; Rodríguez-Juan, Carlos P
2015-04-29
An unsupervised approach to classify surface defects in wire rod manufacturing is developed in this paper. The defects are extracted from an eddy current signal and classified using a clustering technique that uses the dynamic time warping distance as the dissimilarity measure. The new approach has been successfully tested using industrial data. It is shown that it outperforms other classification alternatives, such as the modified Fourier descriptors.
Space Shuttle Columbia Aging Wiring Failure Analysis
NASA Technical Reports Server (NTRS)
McDaniels, Steven J.
2005-01-01
A Space Shuttle Columbia main engine controller 14 AWG wire short circuited during the launch of STS-93. Post-flight examination divulged that the wire had electrically arced against the head of a nearby bolt. More extensive inspection revealed additional damage to the subject wire, and to other wires as well from the mid-body of Columbia. The shorted wire was to have been constructed from nickel-plated copper conductors surrounded by the polyimide insulation Kapton, top-coated with an aromatic polyimide resin. The wires were analyzed via scanning electron microscope (SEM), energy dispersive X-Ray spectroscopy (EDX), and electron spectroscopy for chemical analysis (ESCA); differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA) were performed on the polyimide. Exemplar testing under laboratory conditions was performed to replicate the mechanical damage characteristics evident on the failed wires. The exemplar testing included a step test, where, as the name implies, a person stepped on a simulated wire bundle that rested upon a bolt head. Likewise, a shear test that forced a bolt head and a torque tip against a wire was performed to attempt to damage the insulation and conductor. Additionally, a vibration test was performed to determine if a wire bundle would abrade when vibrated against the head of a bolt. Also, an abrasion test was undertaken to determine if the polyimide of the wire could be damaged by rubbing against convolex helical tubing. Finally, an impact test was performed to ascertain if the use of the tubing would protect the wire from the strike of a foreign object.
Environmental Influence of Gravity and Pressure on Arc Tracking of Insulated Wires Investigated
NASA Technical Reports Server (NTRS)
2005-01-01
Momentary short-circuit arcs between a defective polyimide-insulated wire and another conductor may thermally char (pyrolize) the insulating material. The charred polyimide, being conductive, can sustain the short-circuit arc, which may propagate along the wire through continuous pyrolization of the polyimide insulation (arc tracking). If the arcing wire is part of a multiple-wire bundle, the polyimide insulation of other wires within the bundle may become thermally charred and start arc tracking also (flash over). Such arc tracking can lead to complete failure of an entire wire bundle, causing other critical spacecraft or aircraft failures. Unfortunately, all tested candidate wire insulations for aerospace vehicles were susceptible to arc tracking. Therefore, a test procedure was designed at the NASA Lewis Research Center to select the insulation type least susceptible to arc tracking. This test procedure addresses the following three areas of concern: (1) probability of initiation, (2) probability of reinitiation (restrike), and (3) extent of arc tracking damage (propagation rate). Item 2 (restrike probability) is an issue if power can be terminated from and reapplied to the arcing wire (by a switch, fuse, or resettable circuit breaker). The degree of damage from an arcing event (item 3) refers to how easily the arc chars nearby insulation and propagates along the wire pair. Ease of nearby insulation charring can be determined by measuring the rate of arc propagation. Insulation that chars easily will propagate the arc faster than insulation that does not char very easily. A popular polyimide insulated wire for aerospace vehicles, MIL-W-81381, was tested to determine a degree of damage from an arcing event (item 3) in the following three environments: (1) microgravity with air at 1-atm pressure, (2) 1g with air at 1 atm, and (3) 1g within a 10^-6 Torr vacuum. The microgravity 1-atm air was the harshest environment, with respect to the rate of damage of arc tracking, for the 20 AWG (American Wiring Gauge) MIL-W-81381 wire insulation type . The vacuum environment resulted in the least damage. Further testing is planned to determine if the environmental results are consistent between insulation types and to evaluate the other two parameters associated with arc tracking susceptibility.
A miniature implantable coil that can be wrapped around a tubular organ within the human body
NASA Astrophysics Data System (ADS)
Mao, Shitong; Wang, Hao; Mao, Zhi-Hong; Sun, Mingui
2018-05-01
There are many tubular or rod-shaped organs and tissues within the human body. A miniature medical implant that wraps around such a biological structure can monitor or modulate its function. In order to provide the wrap-around implant with power, a solenoidal coil coupled wirelessly with a planar coil outside the human body can be used. Unfortunately, there is a serious practical problem that this configuration cannot be realized easily because the implantable solenoidal coil cannot be positioned around the tubular biological structure unless either the structure or the coil is cut and reconnected, which is impermissible in most cases. In addition, when a planner exterior coil is used for wireless power transfer and communication, its maximum magnetic coupling with the implanted solenoidal coil is achieved when the tubular structure is perpendicular to the surface of the body. However, in human anatomy, most tubular/rod structures are oriented horizontally. In order to solve these problems, we present a new flexible coil for the class of wrapped-around implantable devices. Our multilayer coil has specially designed windings in cross patterns. The new coil can be made conveniently in high precision at low cost on a flat substrate using the same technology for making the flexible multilayer printed circuit boards along with miniature sensors and electronic circuits. This allows the implant to be made in a flat form and then wrapped around the biostructure during surgery. We present the design of this new coil, perform theoretical analysis with respect to its wireless power transfer efficiency, discuss the effects of coil parameters, and conduct experiments using constructed miniature prototypes. Our results confirm the validity of the new coil.
Thermal resilient multiple jaw braze fixture
Ney, Robert; Perrone, Alex J.
1995-07-11
A braze fixture has side walls forming a cavity with an opening to receive a stack of parts to be brazed. Sidewalls of the housing have a plurality of bearing receiving openings into which bearing rods or jaws are inserted to align the stacked elements of the workpiece. The housing can also have view ports to allow a visual check of the alignment. Straps or wires around the fixture are selected to have thermal characteristics similar to the thermal characteristics of the workpiece undergoing brazing. The straps or wires make physical contact with the bearing rods thereby causing bearing rods to maintain the workpiece in proper alignment throughout the entire brazing cycle.
Confining jackets for concrete cylinders using NiTiNb and NiTi shape memory alloy wires
NASA Astrophysics Data System (ADS)
Choi, Eunsoo; Nam, Tae-Hyun; Yoon, Soon-Jong; Cho, Sun-Kyu; Park, Joonam
2010-05-01
This study used prestrained NiTiNb and NiTi shape memory alloy (SMA) wires to confine concrete cylinders. The recovery stress of the wires was measured with respect to the maximal prestrain of the wires. SMA wires were preelongated during the manufacturing process and then wrapped around concrete cylinders of 150 mm×300 mm (phi×L). Unconfined concrete cylinders were tested for compressive strength and the results were compared to those of cylinders confined by SMA wires. NiTiNb SMA wires increased the compressive strength and ductility of the cylinders due to the confining effect. NiTiNb wires were found to be more effective in increasing the peak strength of the cylinders and dissipating energy than NiTi wires. This study showed the potential of the proposed method to retrofit reinforced concrete columns using SMA wires to protect them from earthquakes.
NASA Astrophysics Data System (ADS)
Pham, Son; Kawara, Zensaku; Yokomine, Takehiko; Kunugi, Tomoaki
2012-11-01
Playing important roles in the mass and heat transfer as well as the safety of boiling water reactor, the liquid film flow on nuclear fuel rods has been studied by different measurement techniques such as ultrasonic transmission, conductivity probe, etc. Obtained experimental data of this annular two-phase flow, however, are still not enough to construct the physical model for critical heat flux analysis especially at the micro-scale. Remain problems are mainly caused by complicated geometry of fuel rod bundles, high velocity and very unstable interface behavior of liquid and gas flow. To get over these difficulties, a new approach using a very high speed digital camera system has been introduced in this work. The test section simulating a 3×3 rectangular rod bundle was made of acrylic to allow a full optical observation of the camera. Image data were taken through Cassegrain optical system to maintain the spatiotemporal resolution up to 7 μm and 20 μs. The results included not only the real-time visual information of flow patterns, but also the quantitative data such as liquid film thickness, the droplets' size and speed distributions, and the tilt angle of wavy surfaces. These databases could contribute to the development of a new model for the annular two-phase flow. Partly supported by the Global Center of Excellence (G-COE) program (J-051) of MEXT, Japan.
Heat transfer enhancement with mixing vane spacers using the field synergy principle
NASA Astrophysics Data System (ADS)
Yang, Lixin; Zhou, Mengjun; Tian, Zihao
2017-01-01
The single-phase heat transfer characteristics in a PWR fuel assembly are important. Many investigations attempt to obtain the heat transfer characteristics by studying the flow features in a 5 × 5 rod bundle with a spacer grid. The field synergy principle is used to discuss the mechanism of heat transfer enhancement using mixing vanes according to computational fluid dynamics results, including a spacer grid without mixing vanes, one with a split mixing vane, and one with a separate mixing vane. The results show that the field synergy principle is feasible to explain the mechanism of heat transfer enhancement in a fuel assembly. The enhancement in subchannels is more effective than on the rod's surface. If the pressure loss is ignored, the performance of the split mixing vane is superior to the separate mixing vane based on the enhanced heat transfer. Increasing the blending angle of the split mixing vane improves heat transfer enhancement, the maximum of which is 7.1%. Increasing the blending angle of the separate mixing vane did not significantly enhance heat transfer in the rod bundle, and even prevented heat transfer at a blending angle of 50°. This finding testifies to the feasibility of predicting heat transfer in a rod bundle with a spacer grid by field synergy, and upon comparison with analyzed flow features only, the field synergy method may provide more accurate guidance for optimizing the use of mixing vanes.
Wire-shaped perovskite solar cell based on TiO2 nanotubes
NASA Astrophysics Data System (ADS)
Wang, Xiaoyan; Kulkarni, Sneha A.; Li, Zhen; Xu, Wenjing; Batabyal, Sudip K.; Zhang, Sam; Cao, Anyuan; Wong, Lydia Helena
2016-05-01
In this work, a wire-shaped perovskite solar cell based on TiO2 nanotube (TNT) arrays is demonstrated for the first time by integrating a perovskite absorber on TNT-coated Ti wire. Anodization was adopted for the conformal growth of TNTs on Ti wire, together with the simultaneous formation of a compact TiO2 layer. A sequential step dipping process is employed to produce a uniform and compact perovskite layer on top of TNTs with conformal coverage as the efficient light absorber. Transparent carbon nanotube film is wrapped around Ti wire as the hole collector and counter electrode. The integrated perovskite solar cell wire by facile fabrication approaches shows a promising future in portable and wearable textile electronics.
Manufacturing and quality control of interconnecting wire harnesses, Volume 2
NASA Technical Reports Server (NTRS)
1972-01-01
Interconnecting wire harnesses defined in the design standard are considered, including type 4, open bundle (not enclosed). Knowledge gained through experience on the Saturn 5 program coupled with recent advances in techniques, materials, and processes was incorporated into the document.
Finite-size polyelectrolyte bundles at thermodynamic equilibrium
NASA Astrophysics Data System (ADS)
Sayar, M.; Holm, C.
2007-01-01
We present the results of extensive computer simulations performed on solutions of monodisperse charged rod-like polyelectrolytes in the presence of trivalent counterions. To overcome energy barriers we used a combination of parallel tempering and hybrid Monte Carlo techniques. Our results show that for small values of the electrostatic interaction the solution mostly consists of dispersed single rods. The potential of mean force between the polyelectrolyte monomers yields an attractive interaction at short distances. For a range of larger values of the Bjerrum length, we find finite-size polyelectrolyte bundles at thermodynamic equilibrium. Further increase of the Bjerrum length eventually leads to phase separation and precipitation. We discuss the origin of the observed thermodynamic stability of the finite-size aggregates.
Gelation And Mechanical Response of Patchy Rods
NASA Astrophysics Data System (ADS)
Kazem, Navid; Majidi, Carmel; Maloney, Craig
We perform Brownian Dynamics simulations to study the gelation of suspensions of attractive, rod-like particles. We show that details of the particle-particle interactions can dramatically affect the dynamics of gelation and the structure and mechanics of the networks that form. If the attraction between the rods is perfectly smooth along their length, they will collapse into compact bundles. If the attraction is sufficiently corrugated or patchy, over time, a rigid space spanning network forms. We study the structure and mechanical properties of the networks that form as a function of the fraction of the surface that is allowed to bind. Surprisingly, the structural and mechanical properties are non-monotonic in the surface coverage. At low coverage, there are not a sufficient number of cross-linking sites to form networks. At high coverage, rods bundle and form disconnected clusters. At intermediate coverage, robust networks form. The elastic modulus and yield stress are both non-monotonic in the surface coverage. The stiffest and strongest networks show an essentially homogeneous deformation under strain with rods re-orienting along the extensional axis. Weaker, clumpy networks at high surface coverage exhibit relatively little re-orienting with strong non-affine deformation. These results suggest design strategies for tailoring surface interactions between rods to yield rigid networks with optimal properties. National Science Foundation and the Air Force Office of Scientific Research.
Molecular weight dependence of LB morphology of poly(n-hexyl isocyanate) (PHIC).
Morioka, Takako; Shibata, Osamu; Kawaguchi, Masami
2010-12-07
The morphologies of Langmuir-Blodgett (LB) films of two fractionated poly(n-hexyl isocyanate) (PHIC) and those of their binary mixtures were observed by AFM, together with those of an unfractionated PHIC. The low molecular weight PHIC formed random packing of bundles consisting of rigid rods, while the high molecular weight PHIC formed random packing of bundles consisting of hairy rods. Bundle interpenetration was observed only for the latter in the semidilute regime. In the bilayer region, the area occupied by the PHIC bundles in the upper layer was obviously smaller for the high molecular weight PHIC than for the low molecular weight PHIC, suggesting that the bundles of high molecular weight PHIC more easily interpenetrate than those of low molecular weight PHIC. For the blended films composed of both low and high molecular weight PHICs, the characteristic morphologies of the respective PHIC samples were no longer present. Moreover, the morphologies of the blended films appeared to resemble each other at any molar fraction owing to the ideal miscibility of the low molecular weight and high molecular weight PHICs. The morphologies of the blended films were also similar to that of the unfractionated PHIC film in the dilute regime. In the semidilute regime, the blended films became rounded owing to an increase in bundles interpenetration between PHICs as compared to that in the dilute regime, whereas the morphology of unfractionated PHIC films remained unchanged as compared to that in the dilute regime.
Thermal resilient multiple jaw braze fixture
Ney, R.; Perrone, A.J.
1995-07-11
A braze fixture has side walls forming a cavity with an opening to receive a stack of parts to be brazed. Sidewalls of the housing have a plurality of bearing receiving openings into which bearing rods or jaws are inserted to align the stacked elements of the workpiece. The housing can also have view ports to allow a visual check of the alignment. Straps or wires around the fixture are selected to have thermal characteristics similar to the thermal characteristics of the workpiece undergoing brazing. The straps or wires make physical contact with the bearing rods thereby causing bearing rods to maintain the workpiece in proper alignment throughout the entire brazing cycle. 9 figs.
An engineering closure for heavily under-resolved coarse-grid CFD in large applications
NASA Astrophysics Data System (ADS)
Class, Andreas G.; Yu, Fujiang; Jordan, Thomas
2016-11-01
Even though high performance computation allows very detailed description of a wide range of scales in scientific computations, engineering simulations used for design studies commonly merely resolve the large scales thus speeding up simulation time. The coarse-grid CFD (CGCFD) methodology is developed for flows with repeated flow patterns as often observed in heat exchangers or porous structures. It is proposed to use inviscid Euler equations on a very coarse numerical mesh. This coarse mesh needs not to conform to the geometry in all details. To reinstall physics on all smaller scales cheap subgrid models are employed. Subgrid models are systematically constructed by analyzing well-resolved generic representative simulations. By varying the flow conditions in these simulations correlations are obtained. These comprehend for each individual coarse mesh cell a volume force vector and volume porosity. Moreover, for all vertices, surface porosities are derived. CGCFD is related to the immersed boundary method as both exploit volume forces and non-body conformal meshes. Yet, CGCFD differs with respect to the coarser mesh and the use of Euler equations. We will describe the methodology based on a simple test case and the application of the method to a 127 pin wire-wrap fuel bundle.
Self-healable electrically conducting wires for wearable microelectronics.
Sun, Hao; You, Xiao; Jiang, Yishu; Guan, Guozhen; Fang, Xin; Deng, Jue; Chen, Peining; Luo, Yongfeng; Peng, Huisheng
2014-09-01
Electrically conducting wires play a critical role in the advancement of modern electronics and in particular are an important key to the development of next-generation wearable microelectronics. However, the thin conducting wires can easily break during use, and the whole device fails to function as a result. Herein, a new family of high-performance conducting wires that can self-heal after breaking has been developed by wrapping sheets of aligned carbon nanotubes around polymer fibers. The aligned carbon nanotubes offer an effective strategy for the self-healing of the electric conductivity, whereas the polymer fiber recovers its mechanical strength. A self-healable wire-shaped supercapacitor fabricated from a wire electrode of this type maintained a high capacitance after breaking and self-healing. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Interactive cutting path analysis programs
NASA Technical Reports Server (NTRS)
Weiner, J. M.; Williams, D. S.; Colley, S. R.
1975-01-01
The operation of numerically controlled machine tools is interactively simulated. Four programs were developed to graphically display the cutting paths for a Monarch lathe, Cintimatic mill, Strippit sheet metal punch, and the wiring path for a Standard wire wrap machine. These programs are run on a IMLAC PDS-ID graphic display system under the DOS-3 disk operating system. The cutting path analysis programs accept input via both paper tape and disk file.
The Effect of Condensate Inundation on Steam Condensation Heat Transfer to Wire-Wrapped Tubing.
1983-06-01
wrapped in a helical manner. The measured condensing coefficient was approximately three times that predicted by the Nusselt equation for a smooth tube...Du. Em0At Block 20 (continued) --"- condensing coefficient measured for 30 smooth tubes was 0.59 times the Nusselt coefficient calculated for the...of 0.029 was found, while it was 0.061 for the roped tubes. The average condensing coefficient measured for 30 smooth tubes was 0.59 times the Nusselt
NASA Astrophysics Data System (ADS)
Wnęk, M.; Górzny, M. Ł.; Ward, M. B.; Wälti, C.; Davies, A. G.; Brydson, R.; Evans, S. D.; Stockley, P. G.
2013-01-01
The rod-shaped plant virus tobacco mosaic virus (TMV) is widely used as a nano-fabrication template, and chimeric peptide expression on its major coat protein has extended its potential applications. Here we describe a simple bacterial expression system for production and rapid purification of recombinant chimeric TMV coat protein carrying C-terminal peptide tags. These proteins do not bind TMV RNA or form disks at pH 7. However, they retain the ability to self-assemble into virus-like arrays at acidic pH. C-terminal peptide tags in such arrays are exposed on the protein surface, allowing interaction with target species. We have utilized a C-terminal His-tag to create virus coat protein-templated nano-rods able to bind gold nanoparticles uniformly. These can be transformed into gold nano-wires by deposition of additional gold atoms from solution, followed by thermal annealing. The resistivity of a typical annealed wire created by this approach is significantly less than values reported for other nano-wires made using different bio-templates. This expression construct is therefore a useful additional tool for the creation of chimeric TMV-like nano-rods for bio-templating.
Materials science: Energy storage wrapped up
NASA Astrophysics Data System (ADS)
Gogotsi, Yury
2014-05-01
Cables and wires are used to conduct electricity, but can they also store energy? The answer is a resounding 'yes', if they are encased by a supercapacitor device -- a finding that might open up many applications.
Organic emitters: Light-emitting fabrics
NASA Astrophysics Data System (ADS)
Ortí, Enrique; Bolink, Henk J.
2015-04-01
Light-emitting fibres that suit integration with textiles are prepared by dip-coating a steel wire with an electroluminescent material and then cleverly wrapping the structure with a carbon nanotube sheet that functions as a transparent electrode.
Annular flow in rod-bundle: Effect of spacer on disturbance waves
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pham, Son H.; Kunugi, Tomoaki
2016-08-01
A high-speed camera technique is used to study the effect of spacers on the disturbance waves present in annular two-phase flow within a rod-bundle geometry. Images obtained using a backlight configuration to visualize the spacer-wave interactions at the micro-scale resolution (in time and space) are discussed. This paper also presents additional images obtained using a reflected light configuration which provides new observations of the disturbance waves. These images show the separation effect caused by the spacer on the liquid film in which the size of generated liquid droplets can be controlled by the gas superficial velocity. Furthermore, the data confirmmore » that the spacer breaks the circumferential coherent structures of the waves.« less
NASA Astrophysics Data System (ADS)
Pan, Jun; Xi, Baojuan; Li, Jingfa; Yan, Yan; Li, Qianwen; Qian, Yitai
2011-08-01
We report a new morphology of wurzite cadmium sulfide with nanoparticles decorated on rod-bundle structures, which were synthesized via calcinations of an inorganic/organic composite at 400 °C in air. The composite was hydrothermally synthesized at 180 °C using thioglycolic acid (TGA) and cadmium acetate as starting materials. The structure, composition, and morphology of the prepared material were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscope, FT-IR spectrometry, photoluminescence spectrometry, and UV-visible spectrometry. Results indicated that the composite could be defined as CdS 0.65/Cd-TGA0.35. X-ray diffraction revealed that the annealed product is CdS with wurtizite phase. The diameter of the rod is about 150-400 nm and the length from the top to the bottom of the decorated nanoparticle is about 100 nm. The composite showed high intensity of photoluminescence with similar peak position, compared to that of wurtzite CdS, because of the structure defects.
Wittig, Holger; Zesch, Stephanie; Rosendahl, Wilfried; Blache, Sandra; Müller-Gerbl, Magdalena; Hotz, Gerhard
2017-01-01
Objective In this study, an Inca bundle was examined using computed tomography (CT). The primary aim was to determine the preservation status of bony and soft tissues, the sex, the age at the time of death, possible indicators for disease or even the cause of death, as well as the kind of mummification. A secondary aim was to obtain a brief overview of the wrapping in order to gain additional information on the cultural background. Materials and methods The bundle belongs to the Museum of Cultures in Basel, Switzerland, and was bought in Munich, Germany, in 1921. Radiocarbon dating of the superficial textile yielded a calibrated age between 1480 and 1650 AD. The mummy was investigated using multi-slice CT with slice thickness of 0.75 mm and 110 kilovolt. For standardized assessment of soft tissue preservation, a recently developed checklist was applied. Results CT revealed the mummy of a seven to nine year old boy with superior preservation of bony and soft tissues allowing detailed assessment. Indicators of neurofibromatosis type 1 (paravertebral and cutaneous neurofibromas, a breast neurofibroma, sphenoid wing dysplasia), Chagas disease (dilatation of the esophagus, stomach, rectum, and large amounts of feces), and lung infection (pleural adherence, calcifications), probably due to tuberculosis, were found. Furthermore, signs of peri-mortem violence (transection of the chest and a defect in the abdominal wall) were detected. CT images revealed a carefully performed wrapping. Conclusion CT examination of the Inca bundle proved to be an important non-destructive examination method. Standardized assessment, especially of the soft tissue structures, allowed for diagnoses of several diseases, indicating a multi-morbid child at the time of death. The careful wrapping pointed to a ceremonial burial. Within the cultural background, the signs of fatal violence were discussed as a possible result of war, murder, accident, or human sacrifice. PMID:28403237
77 FR 51720 - Airworthiness Directives; The Boeing Company Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2012-08-27
... clamps installed within the left environmental cooling systems (ECS) bay, which could allow wiring to... support clamps installed within the left ECS bay, which is a flammable leakage zone. Use of incorrect wire... bundle within the left side ECS bay, and corrective actions if necessary. Corrective actions include...
Coupling procedure for TRANSURANUS and KTF codes
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jimenez, J.; Alglave, S.; Avramova, M.
2012-07-01
The nuclear industry aims to ensure safe and economic operation of each single fuel rod introduced in the reactor core. This goal is even more challenging nowadays due to the current strategy of going for higher burn-up (fuel cycles of 18 or 24 months) and longer residence time. In order to achieve that goal, fuel modeling is the key to predict the fuel rod behavior and lifetime under thermal and pressure loads, corrosion and irradiation. In this context, fuel performance codes, such as TRANSURANUS, are used to improve the fuel rod design. The modeling capabilities of the above mentioned toolsmore » can be significantly improved if they are coupled with a thermal-hydraulic code in order to have a better description of the flow conditions within the rod bundle. For LWR applications, a good representation of the two phase flow within the fuel assembly is necessary in order to have a best estimate calculation of the heat transfer inside the bundle. In this paper we present the coupling methodology of TRANSURANUS with KTF (Karlsruhe Two phase Flow subchannel code) as well as selected results of the coupling proof of principle. (authors)« less
The effect of strain hardening on resistance to electrochemical corrosion of wires for orthopaedics
NASA Astrophysics Data System (ADS)
Przondziono, J.; Walke, W.; Hadasik, E.; Szymszal, J.
2012-05-01
The purpose of this research is to evaluate electrochemical corrosion resistance of wire with modified surface, made of stainless steel of Cr-Ni-Mo type, widely used in implants for orthopaedics, depending on hardening created in the process of drawing. Tests have been carried out in the environment imitating human osseous tissue. Pitting corrosion was determined on the ground of registered anodic polarisation curves by means of potentiodynamic method with application of electrochemical testing system VoltaLab® PGP 201. Wire corrosion tests were carried out in Tyrode solution on samples that were electrochemically polished as well as electrochemically polished and finally chemically passivated. Initial material for tests was wire rod made of X2CrNiMo17-12-2 steel with diameter of 5.5 mm in supersaturated condition. Wire rod was drawn up to diameter of 1.35 mm. This work shows the course of flow curve of wire made of this grade of steel and mathematical form of yield stress function. The study also presents exemplary curves showing the dependence of polarisation resistance in strain function in the drawing process of electrochemically passivated and electrochemically polished and then chemically passivated wire.
NASA requirements and applications environments for electrical power wiring
NASA Technical Reports Server (NTRS)
Stavnes, Mark W.; Hammoud, Ahmad N.
1992-01-01
Serious problems can occur from insulation failures in the wiring harnesses of aerospace vehicles. In most recorded incidents, the failures have been identified to be the result of arc tracking, the propagation of an arc along wiring bundles through degradation of insulation. Propagation of the arc can lead to the loss of the entire wiring harness and the functions which it supports. While an extensive database of testing for arc track resistant wire insulations has been developed for aircraft applications, the counterpart requirements for spacecraft are very limited. The electrical, thermal, mechanical, chemical, and operational requirements for specification and testing of candidate wiring systems for spacecraft applications is presented.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Serell, D.C.; Kaplan, S.
1980-09-01
Purpose of this evaluation is to estimate the magnitude and effects of irradiation and creep induced fuel bundle deformations in the developmental plant. This report focuses on the trends of the results and the ability of present models to evaluate the assembly temperatures in the presence of bundle deformation. Although this analysis focuses on the developmental plant, the conclusions are applicable to LMFBR fuel assemblies in general if they have wire spacers.
Enhanced Condensation Heat Transfer
NASA Astrophysics Data System (ADS)
Rose, John Winston
The paper gives some personal observations on various aspects of enhanced condensation heat transfer. The topics discussed are external condensation (horizontal low-finned tubes and wire-wrapped tubes), internal condensation (microfin tubes and microchannels) and Marangoni condensation of binary mixtures.
The investigation of a compact auto-connected wire-wrapped pulsed transformer
NASA Astrophysics Data System (ADS)
Wang, Yuwei; Zhang, Jiande; Chen, Dongqun; Cao, Shengguang; Li, Da; Zhang, Tianyang
2012-05-01
For the power conditioning circuit used to deliver power efficiently from flux compression generator (FCG) to the load with high impedance, an air-cored and wire-wrapped transformer convenient in coaxial connection to the other parts is investigated. To reduce the size and enhance the performance, an auto-connection is adopted. A fast and simple model is used to calculate the electrical parameters of the transformer. To evaluate the high voltage capability, the voltages across turns and the electric field distribution in the transformer are investigated. The calculated and the measured electrical parameters of the transformer show good agreements. And the safe operating voltage is predicted to exceed 500 kV. In the preliminary experiments, the transformer is tested in a power conditioning circuit with a capacitive power supply. It is demonstrated that the output voltage of the transformer reaches -342 kV under the input voltage of -81 kV.
The investigation of a compact auto-connected wire-wrapped pulsed transformer.
Wang, Yuwei; Zhang, Jiande; Chen, Dongqun; Cao, Shengguang; Li, Da; Zhang, Tianyang
2012-05-01
For the power conditioning circuit used to deliver power efficiently from flux compression generator (FCG) to the load with high impedance, an air-cored and wire-wrapped transformer convenient in coaxial connection to the other parts is investigated. To reduce the size and enhance the performance, an auto-connection is adopted. A fast and simple model is used to calculate the electrical parameters of the transformer. To evaluate the high voltage capability, the voltages across turns and the electric field distribution in the transformer are investigated. The calculated and the measured electrical parameters of the transformer show good agreements. And the safe operating voltage is predicted to exceed 500 kV. In the preliminary experiments, the transformer is tested in a power conditioning circuit with a capacitive power supply. It is demonstrated that the output voltage of the transformer reaches -342 kV under the input voltage of -81 kV.
1981-11-01
Showing Wire . 99 Impregnanted Silicone Rubber Contacts, Chip Carrier, ard Lid 35. Technit Connector For 68-Pad JEDEC Type A Leadless . . 100 Chip Carrier...Points of Various . . . . 124 Solders 4. Composition of Alloys Employed in Dual-In-Line . . . . 128 Package Pins and Plating by Mass Spectrographic...swings, and subnanosecond gate delays and risetimes. Presently, emitter coupled logic (ECL) and current mode logic (CML), both fabricated with silicon tech
Strength of surgical wire fixation. A laboratory study.
Guadagni, J R; Drummond, D S
1986-08-01
Because of the frequent use of stainless steel wire in spinal surgery and to augment fracture fixation, several methods of securing wire fixation were tested in the laboratory to determine the relative strength of fixation. Any method of fixation stronger than the yield strength of the wire is sufficient. Square knots, knot twists, symmetric twists, and the AO loop-tuck techniques afforded acceptable resistance against tension loads, but the wire wrap and AO loop technique were unacceptable. The double symmetric twist, which is frequently used for tension banding, was barely acceptable. The symmetric twist technique was the most practical because it is strong enough, efficient in maintaining tension applied during fixation, and least likely to cause damage to the wire. To optimize the fixation strength of the symmetrical twist, at least two twists are required at a reasonably tight pitch.
Parametric design of tri-axial nested Helmholtz coils
NASA Astrophysics Data System (ADS)
Abbott, Jake J.
2015-05-01
This paper provides an optimal parametric design for tri-axial nested Helmholtz coils, which are used to generate a uniform magnetic field with controllable magnitude and direction. Circular and square coils, both with square cross section, are considered. Practical considerations such as wire selection, wire-wrapping efficiency, wire bending radius, choice of power supply, and inductance and time response are included. Using the equations provided, a designer can quickly create an optimal set of custom coils to generate a specified field magnitude in the uniform-field region while maintaining specified accessibility to the central workspace. An example case study is included.
Parametric design of tri-axial nested Helmholtz coils.
Abbott, Jake J
2015-05-01
This paper provides an optimal parametric design for tri-axial nested Helmholtz coils, which are used to generate a uniform magnetic field with controllable magnitude and direction. Circular and square coils, both with square cross section, are considered. Practical considerations such as wire selection, wire-wrapping efficiency, wire bending radius, choice of power supply, and inductance and time response are included. Using the equations provided, a designer can quickly create an optimal set of custom coils to generate a specified field magnitude in the uniform-field region while maintaining specified accessibility to the central workspace. An example case study is included.
Parametric design of tri-axial nested Helmholtz coils
DOE Office of Scientific and Technical Information (OSTI.GOV)
Abbott, Jake J., E-mail: jake.abbott@utah.edu
This paper provides an optimal parametric design for tri-axial nested Helmholtz coils, which are used to generate a uniform magnetic field with controllable magnitude and direction. Circular and square coils, both with square cross section, are considered. Practical considerations such as wire selection, wire-wrapping efficiency, wire bending radius, choice of power supply, and inductance and time response are included. Using the equations provided, a designer can quickly create an optimal set of custom coils to generate a specified field magnitude in the uniform-field region while maintaining specified accessibility to the central workspace. An example case study is included.
High temperature polymer dielectric film-wire insulation
NASA Technical Reports Server (NTRS)
Nairus, John G.
1994-01-01
The highlights of the program are outlined including two major accomplishments. TRW identified and demonstrated the potential of two aromatic/heterocyclic polymers to have an outstanding and superior combination of electrical, thermal, and chemical resistance properties versus state-of-the-art Kapton for spacecraft and/or aircraft dielectric insulation applications. (Supporting data is provided in tables.) Feasibility was demonstrated for supporting/enabling technologies such as ceramic coatings, continuous film casting, and conductor wire wrapping, which are designed to accelerate qualification and deployment of the new wire insulation materials for USAF systems applications during the mid- to late-1990's.
Californium--palladium metal neutron source material
Dahlen, B.L.; Mosly, W.C. Jr.; Smith, P.K.; Albenesius, E.L.
1974-01-22
Californium, as metal or oxide, is uniformly dispersed throughout a noble metal matrix, provided in compact, rod or wire form. A solution of californium values is added to palladium metal powder, dried, blended and pressed into a compact having a uni-form distribution of californium. The californium values are decomposed to californium oxide or metal by heating in an inert or reducing atmosphere. Sintering the compact to a high density closes the matrix around the dispersed californium. The sintered compact is then mechanically shaped into an elongated rod or wire form. (4 claims, no drawings) (Official Gazette)
Controlled laser production of elongated articles from particulates
Dixon, Raymond D.; Lewis, Gary K.; Milewski, John O.
2002-01-01
It has been discovered that wires and small diameter rods can be produced using laser deposition technology in a novel way. An elongated article such as a wire or rod is constructed by melting and depositing particulate material into a deposition zone which has been designed to yield the desired article shape and dimensions. The article is withdrawn from the deposition zone as it is formed, thus enabling formation of the article in a continuous process. Alternatively, the deposition zone is moved along any of numerous deposition paths away from the article being formed.
78 FR 59304 - Airworthiness Directives; The Boeing Company Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2013-09-26
... ducting with smoke and fire. Incorrectly installed metal clamps, if not corrected, could cause wire bundle... with smoke and fire caused by metal clamps installed on certain hoses. We are issuing this AD to... chaffing, arcing, and burning damage to the control cabin overhead wiring and ducting with smoke and fire...
Sun, Jia-Lin; Zhao, Xingchen; Zhu, Jia-Lin
2008-02-27
Macroscopically long Ag core/Ni shell nanoheterojunctions have been well prepared by a dynamic growth approach. The structure characterized in detail by scanning electron microscopy reveals that the Ag nanowire bundles are wrapped in Ni nanoshields and form multicore coaxial cable frames. Notable photoinduced voltage with a fine repeatability, for irradiation with a laser, is exhibited compared with the case for bulk Ag pole/Ni shell heterojunctions and Ag nanowire bundle/bulk Ni heterojunctions. The prominent photoinduced voltage and the substantial metal nanoscale Ohmic interconnects provided by this kind of nanoheterojunction may have a wide range of applications in the future.
Advanced wiring technique and hardware application: Airplane and space vehicle
NASA Technical Reports Server (NTRS)
Ernst, H. L.; Eichman, C. D.
1972-01-01
An advanced wiring system is described which achieves the safety/reliability required for present and future airplane and space vehicle applications. Also, present wiring installation techniques and hardware are analyzed to establish existing problem areas. An advanced wiring system employing matrix interconnecting unit, plug to plug trunk bundles (FCC or ribbon cable) is outlined, and an installation study presented. A planned program to develop, lab test and flight test key features of these techniques and hardware as a part of the SST technology follow-on activities is discussed.
Polyelectrolyte Bundles: Finite size at thermodynamic equilibrium?
NASA Astrophysics Data System (ADS)
Sayar, Mehmet
2005-03-01
Experimental observation of finite size aggregates formed by polyelectrolytes such as DNA and F-actin, as well as synthetic polymers like poly(p-phenylene), has created a lot of attention in recent years. Here, bundle formation in rigid rod-like polyelectrolytes is studied via computer simulations. For the case of hydrophobically modified polyelectrolytes finite size bundles are observed even in the presence of only monovalent counterions. Furthermore, in the absence of a hydrophobic backbone, we have also observed formation of finite size aggregates via multivalent counterion condensation. The size distribution of such aggregates and the stability is analyzed in this study.
1966-01-01
insulated core is covered by 33 galvanized wires, of which the inner 15 are wrapped in one direction and the outer 18 are wrapped in the reverse...foot marks with Porcelain Enamel Iron Figure Plates. Figure 2•—Non-recording staff gages • Shelters should be well ventilated, especially in...vertical staff gage usually consists of porcelain -enameled iron sections. The sections are usually screwed to a board which is fastened to a suitable
Atmospheric Corrosivity at Australian and Overseas Airbases and Airports
2014-07-01
climatic conditions, the correlation between the GCIA and weight loss data from aluminium alloy coupons exposed in the open at 38 sites in the US...corrosivity. The test consists of an aluminium wire wrapped around a copper bolt exposed in the atmosphere for three months; the weight loss of the wire...Abbreviations/Acronyms AAC Army Aviation Centre AB Air Base ADF Australian Defence Force AFB Air Force Base Al aluminium ANGB Air National Guard Base
NASA Astrophysics Data System (ADS)
Fraldi, M.; Perrella, G.; Ciervo, M.; Bosia, F.; Pugno, N. M.
2017-09-01
Very recently, a Weibull-based probabilistic strategy has been successfully applied to bundles of wires to determine their overall stress-strain behaviour, also capturing previously unpredicted nonlinear and post-elastic features of hierarchical strands. This approach is based on the so-called "Equal Load Sharing (ELS)" hypothesis by virtue of which, when a wire breaks, the load acting on the strand is homogeneously redistributed among the surviving wires. Despite the overall effectiveness of the method, some discrepancies between theoretical predictions and in silico Finite Element-based simulations or experimental findings might arise when more complex structures are analysed, e.g. helically arranged bundles. To overcome these limitations, an enhanced hybrid approach is proposed in which the probability of rupture is combined with a deterministic mechanical model of a strand constituted by helically-arranged and hierarchically-organized wires. The analytical model is validated comparing its predictions with both Finite Element simulations and experimental tests. The results show that generalized stress-strain responses - incorporating tension/torsion coupling - are naturally found and, once one or more elements break, the competition between geometry and mechanics of the strand microstructure, i.e. the different cross sections and helical angles of the wires in the different hierarchical levels of the strand, determines the no longer homogeneous stress redistribution among the surviving wires whose fate is hence governed by a "Hierarchical Load Sharing" criterion.
A Flexible Metamaterial Terahertz Perfect Absorber
NASA Astrophysics Data System (ADS)
Chen, X. R.; Zheng, Y. W.; Qin, L. M.; Wei, G. C.; Qin, Z. P.; Zhang, N. G.; Liu, K.; Li, S. Z.; Wang, S. X.
2017-12-01
We designed a THz matematerial absorber using metallic wires (MWs) and split resonant rings (SRRs). This matematerial absorber exhibits perfect absorption which up to 96% at 4.03 THz and is capable of wrapped around objects because of flexible polyimide dielectric substrate.
Domain and network aggregation of CdTe quantum rods within Langmuir Blodgett monolayers
NASA Astrophysics Data System (ADS)
Zimnitsky, Dmitry; Xu, Jun; Lin, Zhiqun; Tsukruk, Vladimir V.
2008-05-01
Control over the organization of quantum rods was demonstrated by changing the surface area at the air-liquid interface by means of the Langmuir-Blodgett (LB) technique. The LB isotherm of CdTe quantum rods capped with a mixture of alkylphosphines shows a transition point in the liquid-solid state, which is caused by the inter-rod reorganization. As we observed, at low surface pressure the quantum rods are assembled into round-shaped aggregates composed of a monolayer of nanorods packed in limited-size clusters with random orientation. The increase of the surface pressure leads to the rearrangement of these aggregates into elongated bundles composed of uniformly oriented nanorod clusters. Further compression results in denser packing of nanorods aggregates and in the transformation of monolayered domains into a continuous network of locally ordered quantum rods.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Campbell, W.R.; Giovengo, J.F.
1987-10-01
Light Water Breeder Reactor (LWBR) fuel rods were designed to provide a reliable fuel system utilizing thorium/uranium-233 mixed-oxide fuel while simultaneously minimizing structural material to enhance fuel breeding. The fuel system was designed to be capable of operating successfully under both load follow and base load conditions. The breeding objective required thin-walled, low hafnium content Zircaloy cladding, tightly spaced fuel rods with a minimum number of support grid levels, and movable fuel rod bundles to supplant control rods. Specific fuel rod design considerations and their effects on performance capability are described. Successful completion of power operations to over 160 percentmore » of design lifetime including over 200 daily load follow cycles has proven the performance capability of the fuel system. 68 refs., 19 figs., 44 tabs.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tachikawa, K.; Sasaki, H.; Yamaguchi, M.
Tightly consolidated Sn-Ta and Sn-B based alloys have been prepared by the reaction among constituent metal powders at 750-775 deg. C. Sn-Ta and Sn-B based alloys exhibit quite similar microstructures. A small amount of Ti addition seems to improve the bonding between Ta or B particles and Sn matrix. Nb{sub 3}Sn wires have been fabricated by the Jelly Roll (JR) and Multi-rod (MR) process using Sn based alloy sheet and rod, respectively. Thick Nb{sub 3}Sn layers with nearly stoichiometric A15 composition are synthesized through a new diffusion mechanism between Nb and Sn based alloy. B{sub c2}(4.2 K)'s of 26.9 Tmore » (mid) and 26.5 T (mid) have been obtained in the JR and MR processed wires, respectively, using Sn-Ta based alloy. These wires exhibit enough non-Cu J{sub c} to be used above 20 T and 4.2 K. T{sub c} of JR wires using Sn-B based sheet is 18.14 K (offset) which is slightly higher than that of wires using Sn-Ta based sheet.« less
Federal Register 2010, 2011, 2012, 2013, 2014
2012-02-27
... carved to represent a cockle shell; two bundles of sticks, bone spikes and feathers wrapped around an animal tongue; a bone bracelet ornamented in cuts and lines with a plant fiber fastener; a neck ornament... decorated with ivory, bone, deer hooves and brass ornaments; a skin shoulder robe decorated with walrus...
Highly sensitive current sensor utilizing CrNi-wire supported microfiber coils
NASA Astrophysics Data System (ADS)
Xie, Xiaodong; Li, Jie; Sun, Li-Peng; Jin, Long; Guan, Bai-ou
2013-09-01
High current sensitivity is obtained based on a microfiber that is wrapping around a chrome-nickel (CrNi) wire. Due to the strong heating effect of the CrNi wire with the flowing electric current, the mode index and the loop length of microfiber are changed, resulting in the shift of resonant wavelength. The measured current responsivity is as high as 220.65nm/A2, which is in two or three magnitude orders than the previously-obtained ones. We study the influence of component size to the structure performance, which is useful for future applications of current sensing or tuning devices.
A High-Sensitivity Current Sensor Utilizing CrNi Wire and Microfiber Coils
Xie, Xiaodong; Li, Jie; Sun, Li-Peng; Shen, Xiang; Jin, Long; Guan, Bai-ou
2014-01-01
We obtain an extremely high current sensitivity by wrapping a section of microfiber on a thin-diameter chromium-nickel wire. Our detected current sensitivity is as high as 220.65 nm/A2 for a structure length of only 35 μm. Such sensitivity is two orders of magnitude higher than the counterparts reported in the literature. Analysis shows that a higher resistivity or/and a thinner diameter of the metal wire may produce higher sensitivity. The effects of varying the structure parameters on sensitivity are discussed. The presented structure has potential for low-current sensing or highly electrically-tunable filtering applications. PMID:24824372
A high-sensitivity current sensor utilizing CrNi wire and microfiber coils.
Xie, Xiaodong; Li, Jie; Sun, Li-Peng; Shen, Xiang; Jin, Long; Guan, Bai-ou
2014-05-12
We obtain an extremely high current sensitivity by wrapping a section of microfiber on a thin-diameter chromium-nickel wire. Our detected current sensitivity is as high as 220.65 nm/A2 for a structure length of only 35 μm. Such sensitivity is two orders of magnitude higher than the counterparts reported in the literature. Analysis shows that a higher resistivity or/and a thinner diameter of the metal wire may produce higher sensitivity. The effects of varying the structure parameters on sensitivity are discussed. The presented structure has potential for low-current sensing or highly electrically-tunable filtering applications.
NASA Technical Reports Server (NTRS)
Wang, D. S.; Warren, A. D. (Inventor)
1980-01-01
A method for installing fragile, high temperature insulation batting in an elongated cavity or in a resilient wire sleeve to form a resilient seal. The batting is preformed to rough dimensions and wrapped in a plastic film, the film being of a material which is fugitive at a high temperature. The film is heat sealed and trimmed to form a snugly fit skin which overlaps at least at one end to permit attachment of a pull cord. The film absorbs the tensile force of pulling the film enclosed batting through the cavity or wire mesh sleeve and is subsequently driven off by high temperature baking, leaving only the insulation in the cavity or wire mesh sleeve.
A Digital Temperature Control and Measurement System.
1980-07-04
tubing. Vacuum connections, indicated by closed circles, are made with elastomer o-rings. 9.10 The outer vacuum can A is made entirely of aluminum , which...provides good thermal conductivity with minimal weight. Around the outer can is wrapped a 3/8" o.d. aluminum 3 tubing at one turn per inch. The first...through the aluminum tubing. The second stage, radiation shield B. is made entirely of coDper. A heater wire of #32 manganin wire with a total
NASA Astrophysics Data System (ADS)
Satyanarayana, G.; Narayana, K. L.; Boggarapu, Nageswara Rao
2018-03-01
In the nuclear industry, a critical welding process is joining of an end plate to a fuel rod to form a fuel bundle. Literature on zirconium welding in such a critical operation is limited. A CFD model is developed and performed for the three-dimensional non-linear thermo-fluid analysis incorporating buoyancy and Marnangoni stress and specifying temperature dependent properties to predict weld geometry and temperature field in and around the melt pool of laser spot during welding of a zirconium alloy E110 endplate with a fuel rod. Using this method, it is possible to estimate the weld pool dimensions for the specified laser power and laser-on-time. The temperature profiles will estimate the HAZ and microstructure. The adequacy of generic nature of the model is validated with existing experimental data.
NASA Astrophysics Data System (ADS)
Tran, Hanh; Balandraud, Xavier; Destrebecq, Jean-François
2015-02-01
The mechanical response of a bent shape memory alloy (SMA) wire is a key point for the understanding of the process of the creation of confining effects in a wrapped concrete cylinder for example. The objective of the present study is to model the phenomena involved in the bending of a martensitic SMA wire. The mechanism of martensite reorientation is considered in the model, which also takes into account the asymmetry between tension and compression. For validation purposes, experiments were performed on Ni-Ti wires: measurement of residual curvatures after bending release and tensile tests on pre-bent wires. In particular, the analysis shows a variation in axial stiffness as a function of the preliminary curvature. This result shows the necessity of modelling the distributions of the state variables within the wire cross-section for the simulation of confinement processes using SMA wires. It also opens prospects to potential application to the bending of SMA fibres in smart textiles.
Forbidden territories in the string landscape
NASA Astrophysics Data System (ADS)
Kumar, Alok; Mukhopadhyay, Subir; Ray, Koushik
2007-12-01
Problems of stabilizing moduli of the type-IIB string theory on toroidal orientifolds T6/Z2, in presence of worldvolume fluxes on various D-branes, are considered. For Z2 actions, introducing either O9 or O3 planes, we rule out the possibility of moduli stabilization in a wide class of models with Script N = 1 supersymmetry, characterized by the type of fluxes turned on along D-brane worldvolume. Our results, in particular, imply that Abelian worldvolume fluxes can not by themselves stabilize closed string moduli, in a consistent supersymmtric model, for above orientifold compactifications. We also discuss other Z2 orientifolds of T6 and show that certain other brane wrappings are also ruled out by similar consistency requirements. In specific setups we consider examples with D9-branes wrapping on a complex three-torus with its world-volume fluxes taken to be semi-homogeneous bundles and D7-branes wrapping holomorphic four-cycles of the complex three-torus carrying world-volume fluxes.
Comparative Numerical Analysis of Different Strengthening Systems of Historical Brick Arches
NASA Astrophysics Data System (ADS)
Zielińska, M.
2017-05-01
The article presents a comparative numerical analysis of various ways to strengthen historical brick arches. Five ways of strengthening brick arches with steel tie-rods have been proposed. Two of these involve the use of braces wrapped around pillars supporting the arch connected with a tie-rod; the other two ways involve the use of the tie-rods with welded metal sheets of different sizes; the latter involves the use of a tie-rod glued with the use of an epoxy adhesive. The collected data were compared with the reference model of the arch left without any interference. The results make it possible to evaluate the effectiveness of the methods by comparing displacements in the vertical and horizontal direction and stresses. The article indicates the direction of proper planning and design of the arch strengthening in brick structures in historical buildings.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Thomas, D.G.; Baucum, W.E.; Bohanan, R.E.
1977-10-01
The Thermal-Hydraulic Test Facility (THTF) has completed 20 powered rod blowdowns through October 13, 1977. Of these blowdowns, 5 were completed with all 49 rods powered, 2 were completed with 2 inactive rods, and 13 were completed with 4 inactive rods. Initial system pressure was 15.5 MPa, test section inlet temperature was 559 K, and break area was equivalent to a 200% break with the total area usually split between inlet and outlet in the ratio 0.40 : 0.60. Heater rod power was 80, 100, or 122 kW/rod, and the test section temperature was 607 K, 598 K, or 589more » K. Mean time to critical heat flux (CHF) varied from 0.7 to 1.4 sec with delayed CHF of 2.5 sec occurring in the upper half of the bundle in some tests.« less
Method and device for tensile testing of cable bundles
Robertson, Lawrence M; Ardelean, Emil V; Goodding, James C; Babuska, Vit
2012-10-16
A standard tensile test device is improved to accurately measure the mechanical properties of stranded cables, ropes, and other composite structures wherein a witness is attached to the top and bottom mounting blocks holding the cable under test. The witness is comprised of two parts: a top and a bottom rod of similar diameter with the bottom rod having a smaller diameter stem on its upper end and the top rod having a hollow opening in its lower end into which the stem fits forming a witness joint. A small gap is present between the top rod and the larger diameter portion of the bottom rod. A standard extensometer is attached to the top and bottom rods of the witness spanning this small witness gap. When a force is applied to separate the mounting blocks, the gap in the witness expands the same length that the entire test specimen is stretched.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-06-10
... manufacturer. We are issuing this AD to increase the level of protection from lightning strikes and prevent the... of protection from lightning strikes and prevent the potential of ignition sources inside fuel tanks... existing unshielded fuel quantity indication system (FQIS) wire bundles with double shielded FQIS wire...
2013-12-01
tight aluminum box internal view. Each SiPMT is held securely in each aluminum jig with nylon washers and screws. The threaded rod extends length-wise...hole in the aluminum jig located between the threaded rod and nylon screw is the hole where the single BCF-12 scintillating fiber would be placed to...additional pixel firing from the SiPMT. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99 42 A typical Hamamatsu
NASA Astrophysics Data System (ADS)
Najeeb, Umair
This thesis experimentally investigates the enhancement of single-phase heat transfer, frictional loss and pressure drop characteristics in a Single Heater Element Loop Tester (SHELT). The heater element simulates a single fuel rod for Pressurized Nuclear reactor. In this experimental investigation, the effect of the outer surface roughness of a simulated nuclear rod bundle was studied. The outer surface of a simulated fuel rod was created with a three-dimensional (Diamond-shaped blocks) surface roughness. The angle of corrugation for each diamond was 45 degrees. The length of each side of a diamond block is 1 mm. The depth of each diamond block was 0.3 mm. The pitch of the pattern was 1.614 mm. The simulated fuel rod had an outside diameter of 9.5 mm and wall thickness of 1.5 mm and was placed in a test-section made of 38.1 mm inner diameter, wall thickness 6.35 mm aluminum pipe. The Simulated fuel rod was made of Nickel 200 and Inconel 625 materials. The fuel rod was connected to 10 KW DC power supply. The Inconel 625 material of the rod with an electrical resistance of 32.3 kO was used to generate heat inside the test-section. The heat energy dissipated from the Inconel tube due to the flow of electrical current flows into the working fluid across the rod at constant heat flux conditions. The DI water was employed as working fluid for this experimental investigation. The temperature and pressure readings for both smooth and rough regions of the fuel rod were recorded and compared later to find enhancement in heat transfer coefficient and increment in the pressure drops. Tests were conducted for Reynold's Numbers ranging from 10e4 to 10e5. Enhancement in heat transfer coefficient at all Re was recorded. The maximum heat transfer co-efficient enhancement recorded was 86% at Re = 4.18e5. It was also observed that the pressure drop and friction factor increased by 14.7% due to the increased surface roughness.
49 CFR 571.139 - Standard No. 139; New pneumatic radial tires for light vehicles.
Code of Federal Regulations, 2011 CFR
2011-10-01
... means the part of the tire that is made of steel wires, wrapped or reinforced by ply cords and that is... mechanical device made of rubber, chemicals, fabric and steel or other materials, that, when mounted on an...
Motor-mediated microtubule self-organization in dilute and semi-dilute filament solutions.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Swaminathan, S.; Ziebert, F.; Aranson, I. S.
We study molecular motor-induced microtubule self-organization in dilute and semi-dilute filament solutions. In the dilute case, we use a probabilistic model of microtubule interaction via molecular motors to investigate microtubule bundle dynamics. Microtubules are modeled as polar rods interacting through fully inelastic, binary collisions. Our model indicates that initially disordered systems of interacting rods exhibit an orientational instability resulting in spontaneous ordering. We study the existence and dynamic interaction of microtubule bundles analytically and numerically. Our results reveal a long term attraction and coalescing of bundles indicating a clear coarsening in the system; microtubule bundles concentrate into fewer orientations onmore » a slow logarithmic time scale. In semi-dilute filament solutions, multiple motors can bind a filament to several others and, for a critical motor density, induce a transition to an ordered phase with a nonzero mean orientation. Motors attach to a pair of filaments and walk along the pair bringing them into closer alignment. We develop a spatially homogenous, mean-field theory that explicitly accounts for a force-dependent detachment rate of motors, which in turn affects the mean and the fluctuations of the net force acting on a filament. We show that the transition to the oriented state can be both continuous and discontinuous when the force-dependent detachment of motors is important.« less
2008-01-13
KENNEDY SPACE CENTER, FLA. -- Lloyd Johns, with Lockheed Martin, prepares the area where the replacement feed-through connector in the engine cutoff, or ECO, sensor system on space shuttle Atlantis' external tank will be installed. Seen next to Johns' arm is the internal connector. The area is wrapped in material for weather protection. Berger wears safety equipment as helium gas is employed to keep the equipment under wrap dry. The feed-through connector passes the wires from the inside of the tank to the outside. Results of a tanking test on Dec. 18 pointed to an open circuit in the feed-through connector wiring, which is located at the base of the tank. The pins in the replacement connector have been precisely soldered to create a connection that allows sensors inside the tank to send signals to the computers onboard Atlantis. The work is being done on Launch Pad 39A. Space shuttle Atlantis is now targeted for launch on Feb. 7. Photo credit: NASA/George Shelton
2012-05-04
Wrapping Pre-impregnated CFRP unidirectional and +/-45° woven carbon fiber fabric prepreg was used for the loop. Pre-impregnated material was a...viable application for the connecting rod because there are no complex geometries for the CFRP to negotiate. Prepreg aids in maintaining proper fiber
Process for producing fine and ultrafine filament superconductor wire
Kanithi, H.C.
1992-02-18
A process for producing a superconductor wire made up of a large number of round monofilament rods is provided for, comprising assembling a multiplicity of round monofilaments inside each of a multiplicity of thin wall hexagonal tubes and then assembling a number of said thin wall hexagonal tubes within an extrusion can and subsequently consolidating, extruding and drawing the entire assembly down to the desired wire size. 8 figs.
Process for producing fine and ultrafine filament superconductor wire
Kanithi, Hem C.
1992-01-01
A process for producing a superconductor wire made up of a large number of round monofilament rods is provided for, comprising assembling a multiplicity of round monofilaments inside each of a multiplicity of thin wall hexagonal tubes and then assembling a number of said thin wall hexagonal tubes within an extrusion can and subsequently consolidating, extruding and drawing the entire assembly down to the desired wire size.
NASA Technical Reports Server (NTRS)
Mccandles, L. C.; Davies, L. G.
1973-01-01
Techniques were studied to reinforce or strengthen electroformed nickel to allow a fuller utilization of electroforming as a reliable and low cost fabrication technique for regenerately cooled thrust chambers. Techniques for wire wrapping while electrodepositing were developed that can result in a structurally strong wall with less weight than a conventional electroformed wall. Also a technique of codepositing submicron sized THO2 particles with the nickel to form a dispersion strengthened structure was evaluated. The standard nickel cylinders exhibited an average hoop strength of 80,000 psi with a yield strength of 65,000 psi and a modulus of 25.6 x 10 to the 6th power psi. The as produced dispersion strengthened nickel showed a hoop strength of 97,000 psi with a yield strength of 67,000 psi. This is an increase of 17,000 psi or 21% over the standard nickel hoop strength. The wire wrapping cylinders showed an increased strength over the standard nickel test samples of 26,000 to 66,800 psi which is in the range of 26 to 104% increase in strength over the base standard nickel. These latter test results are indicative of a volume percent wire reinforcement from 15 to 31. The measured hoop strengths agree with calculated composite strengths based upon rule of mixtures.
ERIC Educational Resources Information Center
Ladino, L. A.; Rondón, S. H.
2015-01-01
In this paper, we present a low-cost method to study the Gay-Lussac's law. We use a heating wire wrapped around the test tube to heat the air inside and make use of a solid state pressure sensor which requires a previous calibration to measure the pressure in the test tube.
Occurrence of two-stage hardening in C-Mn steel wire rods containing pearlitic microstructure
NASA Astrophysics Data System (ADS)
Singh, Balbir; Sahoo, Gadadhar; Saxena, Atul
2016-09-01
The 8 and 10 mm diameter wire rods intended for use as concrete reinforcement were produced/ hot rolled from C-Mn steel chemistry containing various elements within the range of C:0.55-0.65, Mn:0.85-1.50, Si:0.05-0.09, S:0.04 max, P:0.04 max and N:0.006 max wt%. Depending upon the C and Mn contents the product attained pearlitic microstructure in the range of 85-93% with balance amount of polygonal ferrite transformed at prior austenite grain boundaries. The pearlitic microstructure in the wire rods helped in achieving yield strength, tensile strength, total elongation and reduction in area values within the range of 422-515 MPa, 790-950 MPa, 22-15% and 45-35%, respectively. On analyzing the tensile results it was revealed that the material experienced hardening in two stages separable by a knee strain value of about 0.05. The occurrence of two stage hardening thus in the steel with hardening coefficients of 0.26 and 0.09 could be demonstrated with the help of derived relationships existed between flow stress and the strain.
Nagamine, Kuniaki; Sato, Hirotaka; Kai, Hiroyuki; Kaji, Hirokazu; Kanzaki, Makoto; Nishizawa, Matsuhiko
2018-02-02
Contractile skeletal muscle cells were cultured so as to wrap around an electrode wire to enable their selective stimulation even when they were co-cultured with other electrically-excitable cells. Since the electrode wire was composed of the conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT) and polyurethane (PU), which is soft and highly capacitive (~10 mF cm -2 ), non-faradaic electrical stimulation with charge/discharge currents could be applied to the surrounding cells without causing significant damage even for longer periods (more than a week). The advantage of this new culture system was demonstrated in the study of chemotactic interaction of monocytes and skeletal muscle cells via myokines.
Development and preclinical testing of a new tension-band device for the spine: the Loop system.
Garner, Matthew D; Wolfe, Steven J; Kuslich, Stephen D
2002-10-01
Wire sutures, cerclage constructs, and tension bands have been used for many years in orthopedic surgery. Spinous process and sublaminar wires and other strands or cables are used in the spine to re-establish stability of the posterior spinal ligament complex. Rigid monofilament wires often fail due to weakening created during twisting or wrapping. Stronger metal cables do not conform well to bony surfaces. Polyethylene cables have higher fatigue strength than metal cables. The Loop cable is a pliable, radiolucent, polyethylene braid. Creep of the Loop/locking clip construct is similar to metal cable constructs using crimps. Both systems have less creep than knotted polyethylene cable constructs.
Two-stage epitaxial growth of vertically-aligned SnO 2 nano-rods on(001) ceria
Solovyov, Vyacheslav F.; Wu, Li-jun; Rupich, Martin W.; ...
2014-09-20
Growth of high-aspect ratio oriented tin oxide, SnO 2, nano-rods is complicated by a limited choice of matching substrates. We show that a (001) cerium oxide, CeO 2, surface uniquely enables epitaxial growth of tin-oxide nano-rods via a two-stage process. First, (100) oriented nano-wires coat the ceria surface by lateral growth, forming a uniaxially-textured SnO 2 deposit. Second, vertical SnO 2nano-rods nucleate on the deposit by homoepitaxy. We demonstrate growth of vertically oriented 1-2 μm long nano-rods with an average diameter of ≈20 nm.
2017-11-01
Front view of the drift gas showerhead assembly showing the Faraday plate and insulating ceramic cemented in the center, (left) the drift gas...drift gas was preheated using a heater built in-house at WSU, which consisted of an 8 in. length of 1/8 in. stainless steel tubing wrapped with 3 ft...gate halves were then cemented together with an array of parallel 0.003 in. o.d. Alloy 46 wires (California Fine Wire Company) were spaced between them
NASA Technical Reports Server (NTRS)
Patterson, Ashley; Sikes, Larry; Corbin, Cheryl; Rucka, Rebecca
2015-01-01
Special processes require special skills, knowledge and experienced application. For over 15 years, the NASA Johnson Space Center's Receiving, Inspection and Test Facility (RITF) has provided Workmanship Standards compliance training, issuing more than 500 to 800 training completion certificates annually. It is critical that technicians and inspectors are trained and that they maintain their proficiency to implement the applicable standards and specifications. Training services include 'hands-on' training to engineers, technicians, and inspectors in the areas of electrostatic discharge (ESD), soldering, fiber optics, lithium battery handling, torque and wire safety, and wire wrapping.
The confining effectiveness of NiTiNb and NiTi SMA wire jackets for concrete
NASA Astrophysics Data System (ADS)
Choi, Eunsoo; Chung, Young-Soo; Choi, Jun-Hyeok; Kim, Hong-Taek; Lee, Hacksoo
2010-03-01
The purpose of this study is to assess the confining effectiveness of shape memory alloy (SMA) wire jackets for concrete. The performance of SMA wire jackets was compared to that of steel jackets. A prestrained martensitic SMA wire was wrapped around a concrete cylinder and then heated by a heating jacket. In the process, a confining stress around the cylinder was developed in the SMA wire due to the shape memory effect; this jacketing method can increase the strength and ductility of the cylinder under an axial compressive load. In this study, NiTi and NiTiNb SMA wires of 1.0 mm in diameter were used for the confinement. Recovery tests were conducted on the wires to assess their recovery and residual stress. The confinement by SMA wire jackets increased the strength slightly and greatly increased the ductility compared to the strength and ductility of plain concrete cylinders. The NiTiNb SMA wire jacket showed better performance than that of the NiTi SMA wire jacket. The confining effectiveness of the SMA wire jackets of this study was estimated to be similar to that of the steel jackets. This study showed the potential of the SMA wire jacketing method to retrofit reinforced concrete columns and protect them from seismic risks.
NASA Astrophysics Data System (ADS)
Verma, Shashi Kant; Sinha, S. L.; Chandraker, D. K.
2018-05-01
Numerical simulation has been carried out for the study of natural mixing of a Tracer (Passive scalar) to describe the development of turbulent diffusion in an injected sub-channel and, afterwards on, cross-mixing between adjacent sub-channels. In this investigation, post benchmark evaluation of the inter-subchannel mixing was initiated to test the ability of state-of-the-art Computational Fluid Dynamics (CFD) codes to numerically predict the important turbulence parameters downstream of a ring type spacer grid in a rod-bundle. A three-dimensional Computational Fluid Dynamics (CFD) tool (STAR-CCM+) was used to model the single phase flow through a 30° segment or 1/12th of the cross segment of a 54-rod bundle with a ring shaped spacer grid. Polyhedrons were used to discretize the computational domain, along with prismatic cells near the walls, with an overall mesh count of 5.2 M cell volumes. The Reynolds Stress Models (RSM) was tested because of RSM accounts for the turbulence anisotropy, to assess their capability in predicting the velocities as well as mass fraction of potassium nitrate measured in the experiment. In this way, the line probes are located in the different position of subchannels which could be used to characterize the progress of the mixing along the flow direction, and the degree of cross-mixing assessed using the quantity of tracer arriving in the neighbouring sub-channels. The predicted dimensionless mixing scalar along the length, however, was in good agreement with the measurements downstream of spacers.
1989-12-01
ILLUSTRATIONS (CONTD) 44 Tubular strut wire - bending energy absorber ...... ........... 91 45 Inversion tube concepL with typical force-deformation...expected from a rod-bending sled decelerator and a wire - bending seat load limiter (Refer- ences 35 and 36). Therefore, correcting the calculated...attaching the seat bucket to the rollers, compressive as well as tensile loads can be sustained. Two variations of the wire - bending device have been
Microstructures and Mechanical Properties of as-Drawn and Laboratory Annealed Pearlitic Steel Wires
NASA Astrophysics Data System (ADS)
Durgaprasad, A.; Giri, S.; Lenka, S.; Kundu, S.; Mishra, S.; Chandra, S.; Doherty, R. D.; Samajdar, I.
2017-10-01
Near eutectoid fully pearlitic wire rod (5.5 mm diameter) was taken through six stages of wire drawing (drawing strains of 0 to 2.47). The as-drawn (AD) wires were further laboratory annealed (LA) to re-austenitize and reform the pearlite. AD and LA grades, for respective wire diameters, had similar pearlite microstructure: interlamellar spacing ( λ) and pearlite alignment with the wire axis. However, LA grade had lower hardness (for both phases) and slightly lower fiber texture and residual stresses in ferrite. Surprisingly, essentially identical tensile yield strengths in AD and LA wires, measured at equivalent spacing, were found. The work hardened AD had, as expected, higher torsional yield strengths and lower tensile and torsional ductilities than LA. In both wires, stronger pearlite alignment gave significantly increased torsional ductility.
NASA Technical Reports Server (NTRS)
Stueber, Thomas J.; Mundson, Chris
1993-01-01
Kapton polyimide wiring insulation was found to be vulnerable to pyrolization, arc tracking, and flashover when momentary short-circuit arcs have occurred on aircraft power systems. Short-circuit arcs between wire pairs can pyrolize the polyimide resulting in a conductive char between conductors that may sustain the arc (arc tracking). Furthermore, the arc tracking may spread (flashover) to other wire pairs within a wire bundle. Polyimide Kapton will also be used as the insulating material for the flexible current carrier (FCC) of Space Station Freedom (SSF). The FCC, with conductors in a planar type geometric layout as opposed to bundles, is known to sustain arc tracking at proposed SSF power levels. Tests were conducted in a vacuum bell jar that was designed to conduct polyimide pyrolysis, arc tracking, and flashover studies on samples of SSF's FCC. Test results will be reported concerning the minimal power level needed to sustain arc tracking and the FCC susceptibility to flashover. Results of the FCC arc tracking tests indicate that only 22 volt amps were necessary to sustain arc tracking (proposed SSF power level is 400 watts). FCC flashover studies indicate that the flashover event is highly unlikely.
Wheelock, C.W.; Baumeister, E.B.
1961-09-01
A reactor fuel element utilizing fissionable fuel materials in plate form is described. This fuel element consists of bundles of fuel-bearing plates. The bundles are stacked inside of a tube which forms the shell of the fuel element. The plates each have longitudinal fins running parallel to the direction of coolant flow, and interspersed among and parallel to the fins are ribs which position the plates relative to each other and to the fuel element shell. The plate bundles are held together by thin bands or wires. The ex tended surface increases the heat transfer capabilities of a fuel element by a factor of 3 or more over those of a simple flat plate.
RCS of resonant scatterers with attached wires
NASA Astrophysics Data System (ADS)
Trueman, C. W.; Mishra, S. R.; Kubina, S. J.; Larose, C. L.
1993-03-01
Some aircraft carry wire antennas for HF communication. This paper investigates the effect of such wires on the radar cross section (RCS) at HF frequencies by comparing the RCS of a strip, a cylinder, and a rod with and without an attached wire. The RCS is found for broadside incidence and for end-on incidence of the plane wave for scatterer lengths from 0.4 to 3.8 wavelengths, typical of aircraft size at HF frequencies. It is shown that the RCS of such fuselage-like targets with a wire 'antenna' is quite different from that of the targets without the wire. For broadside incidence, the wire contributes a sharp peak-and-trough to the RCS at the wire's fundamental resonant frequency. For end-on incidence the wire considerably enhances the RCS at frequencies making its length odd multiples of the quarter-wave.
Two-stage epitaxial growth of vertically-aligned SnO2 nano-rods on (001) ceria
DOE Office of Scientific and Technical Information (OSTI.GOV)
Solovyov, VF; Wu, LJ; Rupich, MW
2014-12-15
Growth of high-aspect ratio oriented tin oxide, SnO2, nano-rods is complicated by a limited choice of matching substrates. We show that a (001) cerium oxide, CeO2, surface uniquely enables epitaxial growth of tin-oxide nano-rods via a two-stage process. First, (100) oriented nano-wires coat the ceria surface by lateral growth, forming a uniaxially-textured SnO2 deposit. Second, vertical SnO2 nano-rods nucleate on the deposit by homoepitaxy. We demonstrate growth of vertically oriented 1-2 mu m long nano-rods with an average diameter of approximate to 20 nm. 2014 Elsevier B.V. All rights reserved.
Ordering of Glass Rods in Nematic and Cholesteric Liquid Crystals
2011-12-01
3), 483–508 (2007). 2. M. D. Lynch and D. L. Patrick, “Controlling the orientation of micron-sized rod-shaped SiC particles with nematic liquid...Elastic torque and the levitation of metal wires by a nematic liquid crystal,” Science 303(5658), 652–655 (2004). 17. R. Eelkema, M. M. Pollard, J...Building Blocks for Iterative Methods, 2nd ed. (SIAM, 1994). 1. Introduction Incorporating rod-like particles into liquid crystal (LC) media can lead
Bundling of elastic filaments induced by hydrodynamic interactions
NASA Astrophysics Data System (ADS)
Man, Yi; Page, William; Poole, Robert J.; Lauga, Eric
2017-12-01
Peritrichous bacteria swim in viscous fluids by rotating multiple helical flagellar filaments. As the bacterium swims forward, all its flagella rotate in synchrony behind the cell in a tight helical bundle. When the bacterium changes its direction, the flagellar filaments unbundle and randomly reorient the cell for a short period of time before returning to their bundled state and resuming swimming. This rapid bundling and unbundling is, at its heart, a mechanical process whereby hydrodynamic interactions balance with elasticity to determine the time-varying deformation of the filaments. Inspired by this biophysical problem, we present in this paper what is perhaps the simplest model of bundling whereby two or more straight elastic filaments immersed in a viscous fluid rotate about their centerline, inducing rotational flows which tend to bend the filaments around each other. We derive an integrodifferential equation governing the shape of the filaments resulting from mechanical balance in a viscous fluid at low Reynolds number. We show that such equation may be evaluated asymptotically analytically in the long-wavelength limit, leading to a local partial differential equation governed by a single dimensionless bundling number. A numerical study of the dynamics predicted by the model reveals the presence of two configuration instabilities with increasing bundling numbers: first to a crossing state where filaments touch at one point and then to a bundled state where filaments wrap along each other in a helical fashion. We also consider the case of multiple filaments and the unbundling dynamics. We next provide an intuitive physical model for the crossing instability and show that it may be used to predict analytically its threshold and adapted to address the transition to a bundling state. We then use a macroscale experimental implementation of the two-filament configuration in order to validate our theoretical predictions and obtain excellent agreement. This long-wavelength model of bundling will be applicable to other problems in biological physics and provides the groundwork for further, more realistic, models of flagellar bundling.
Manipulating flexible parts using a teleoperated system with time delay: An experiment
NASA Technical Reports Server (NTRS)
Kotoku, T.; Takamune, K.; Tanie, K.; Komoriya, K.; Matsuhira, N.; Asakura, M.; Bamba, H.
1994-01-01
This paper reports experiments involving the handling of flexible parts (e.g. wires) when using a teleoperated system with time delay. The task is principally a peg-in-hole task involving the wrapping of a wire around two posts on the task-board. It is difficult to estimate the effects of the flexible parts; therefore, on-line teleoperation is indispensable for this class of unpredictable task. We first propose a teleoperation system based on the predictive image display, then describe an experimental teleoperation testbed with a four second transmission time delay. Finally, we report on wire handling operations that were performed to evaluate the performance of this system. Those experiments will contribute to future advanced experiments for the MITI ETS-7 mission.
7 CFR 1755.200 - RUS standard for splicing copper and fiber optic cables.
Code of Federal Regulations, 2010 CFR
2010-01-01
...) Color coded plastic tie wraps shall be placed loosely around each binder group of cables before splicing... conform to the same color designations as the binder ribbons. Twisted wire pigtails shall not be used to identify binder groups due to potential transmission degradation. (ii) The standard insulation color code...
A low cost, disposable cable-shaped Al-air battery for portable biosensors
NASA Astrophysics Data System (ADS)
Fotouhi, Gareth; Ogier, Caleb; Kim, Jong-Hoon; Kim, Sooyeun; Cao, Guozhong; Shen, Amy Q.; Kramlich, John; Chung, Jae-Hyun
2016-05-01
A disposable cable-shaped flexible battery is presented using a simple, low cost manufacturing process. The working principle of an aluminum-air galvanic cell is used for the cable-shaped battery to power portable and point-of-care medical devices. The battery is catalyzed with a carbon nanotube (CNT)-paper matrix. A scalable manufacturing process using a lathe is developed to wrap a paper layer and a CNT-paper matrix on an aluminum wire. The matrix is then wrapped with a silver-plated copper wire to form the battery cell. The battery is activated through absorption of electrolytes including phosphate-buffered saline, NaOH, urine, saliva, and blood into the CNT-paper matrix. The maximum electric power using a 10 mm-long battery cell is over 1.5 mW. As a demonstration, an LED is powered using two groups of four batteries in parallel connected in series. Considering the material composition and the cable-shaped configuration, the battery is fully disposable, flexible, and potentially compatible with portable biosensors through activation by either reagents or biological fluids.
The Expected but Well-Hidden EMF in the Jumping Wire Experiment and Its Unexpected Role
ERIC Educational Resources Information Center
Donoso, G.; Ladera, C. L.
2015-01-01
As presented in physics textbooks, as well as in a few papers, the typical example of an induced motional electromotive force e[subscript mot] = "Blv" consists of a conductive rod of length "l" frictionlessly sliding with speed v along parallel wires within an orthogonal and constant uniform magnetic field of magnitude…
NASA Astrophysics Data System (ADS)
Granger, G.; Kam, A.; Studenikin, S. A.; Sachrajda, A. S.; Aers, G. C.; Williams, R. L.; Poole, P. J.
2010-09-01
The purpose of this work is to fabricate ribbon-like InGaAs and InAsP wires embedded in InP ridge structures and investigate their transport properties. The InP ridge structures that contain the wires are selectively grown by chemical beam epitaxy (CBE) on pre-patterned InP substrates. To optimize the growth and micro-fabrication processes for electronic transport, we explore the Ohmic contact resistance, the electron density, and the mobility as a function of the wire width using standard transport and Shubnikov-de Haas measurements. At low temperatures the ridge structures reveal reproducible mesoscopic conductance fluctuations. We also fabricate ridge structures with submicron gate electrodes that exhibit non-leaky gating and good pinch-off characteristics acceptable for device operation. Using such wrap gate electrodes, we demonstrate that the wires can be split to form quantum dots evidenced by Coulomb blockade oscillations in transport measurements.
Prognostic monitoring of aircraft wiring using electrical capacitive tomography
NASA Astrophysics Data System (ADS)
McKenzie, G.; Record, P.
2011-12-01
Electrical capacitive tomography (ECT) has been used to monitor sections of aircraft wiring, as a tool for prognostic analysis. To apply the principles of ECT across a cross section of only 4 mm, modification of the basic circuit was required. Additionally, a more novel method of placing the necessary electrodes was needed, this being accomplished by etching them from flexible copper sheeting and wrapping them inside the perimeter of an enclosure. Results showed that at this small scale, it was possible to determine the position of a wire-under-test inside the 4 mm diameter enclosure to about 0.1 mm, and that by measuring capacitance between pairs, it was also possible to determine whether or not the insulation of wire passed between the electrodes was damaged. With more than one wire-under-test present, it was possible to determine whether or not damage was present, and if so, which wire was damaged. By detecting insulation damage in this way, ECT has proven to be a useful tool in prognostic monitoring, helping faults to be found before they become safety-critical onboard an aircraft.
Prognostic monitoring of aircraft wiring using electrical capacitive tomography.
McKenzie, G; Record, P
2011-12-01
Electrical capacitive tomography (ECT) has been used to monitor sections of aircraft wiring, as a tool for prognostic analysis. To apply the principles of ECT across a cross section of only 4 mm, modification of the basic circuit was required. Additionally, a more novel method of placing the necessary electrodes was needed, this being accomplished by etching them from flexible copper sheeting and wrapping them inside the perimeter of an enclosure. Results showed that at this small scale, it was possible to determine the position of a wire-under-test inside the 4 mm diameter enclosure to about 0.1 mm, and that by measuring capacitance between pairs, it was also possible to determine whether or not the insulation of wire passed between the electrodes was damaged. With more than one wire-under-test present, it was possible to determine whether or not damage was present, and if so, which wire was damaged. By detecting insulation damage in this way, ECT has proven to be a useful tool in prognostic monitoring, helping faults to be found before they become safety-critical onboard an aircraft.
Comparison of Arc Tracking Tests in Various Aerospace Environments
NASA Technical Reports Server (NTRS)
Stueber, Thomas J.; Hammoud, Ahmad; McCall, David
1996-01-01
Momentary short-circuit arcs between a polyimide insulated wire with defective insulation and another conductor may cause pyrolization of the insulation resulting in a conductive path capable of sustaining the arc. These sustained arcs may propagate along the wires or to neighboring wires leading to complete failure of the wire bundle. Wire insulation susceptibility to arc tracking may be dependent on its environment. Because all wire insulation types tested to date arc track, a test procedure has been developed to compare different insulation types with respect to their arc tracking susceptibility. This test procedure is presented along with a comparison of arc tracking in the following three environments: (1) Air at atmospheric pressure and 1 gravitational(g) force; (2) Vacuum (2.67 x 10(exp -3) Pa) and 1g, and (3) Air at atmospheric pressure and microgravity (less than 0.04g).
CTF Preprocessor User's Manual
DOE Office of Scientific and Technical Information (OSTI.GOV)
Avramova, Maria; Salko, Robert K.
2016-05-26
This document describes how a user should go about using the CTF pre- processor tool to create an input deck for modeling rod-bundle geometry in CTF. The tool was designed to generate input decks in a quick and less error-prone manner for CTF. The pre-processor is a completely independent utility, written in Fortran, that takes a reduced amount of input from the user. The information that the user must supply is basic information on bundle geometry, such as rod pitch, clad thickness, and axial location of spacer grids--the pre-processor takes this basic information and determines channel placement and connection informationmore » to be written to the input deck, which is the most time-consuming and error-prone segment of creating a deck. Creation of the model is also more intuitive, as the user can specify assembly and water-tube placement using visual maps instead of having to place them by determining channel/channel and rod/channel connections. As an example of the benefit of the pre-processor, a quarter-core model that contains 500,000 scalar-mesh cells was read into CTF from an input deck containing 200,000 lines of data. This 200,000 line input deck was produced automatically from a set of pre-processor decks that contained only 300 lines of data.« less
Thermal Modeling of the Injection of Standard and Thermally Insulated Cored Wire
NASA Astrophysics Data System (ADS)
Castro-Cedeno, E.-I.; Jardy, A.; Carré, A.; Gerardin, S.; Bellot, J. P.
2017-12-01
Cored wire injection is a widespread method used to perform alloying additions during ferrous and non-ferrous liquid metal treatment. The wire consists of a metal casing that is tightly wrapped around a core of material; the casing delays the release of the material as the wire is immersed into the melt. This method of addition presents advantages such as higher repeatability and yield of cored material with respect to bulk additions. Experimental and numerical work has been performed by several authors on the subject of alloy additions, spherical and cylindrical geometries being mainly considered. Surprisingly this has not been the case for cored wire, where the reported experimental or numerical studies are scarce. This work presents a 1-D finite volume numerical model aimed for the simulation of the thermal phenomena which occurs when the wire is injected into a liquid metal bath. It is currently being used as a design tool for the conception of new types of cored wire. A parametric study on the effect of injection velocity and steel casing thickness for an Al cored wire immersed into a steel melt at 1863 K (1590 °C) is presented. The standard single casing wire is further compared against a wire with multiple casings. Numerical results show that over a certain range of injection velocities, the core contents' release is delayed in the multiple casing when compared to a single casing wire.
Gelfi, Marcello; Solazzi, Luigi; Poli, Sandro
2017-03-06
This study is a detailed failure analysis of galvanized high carbon steel wires, which developed coating cracks during the torsion test performed as a quality control at the end of the manufacturing process. Careful visual inspections showed that the cracks are already present in the coating before the torsion test. In order to explain the origin of these cracks, systematic metallographic investigations were performed by means of optical and scanning electron microscope on both the wires and the rods that have been cold drawn to produce the wire. The chemical composition of the galvanized coatings was evaluated by means of energy dispersive spectroscopy. Micro bidimensional X-ray diffraction experiments were also performed to measure the residual stresses in the galvanized coating. The results showed that the failure is related to two main factors: the relatively high content of silicon in the steel and the unsuitable cooling rate of the rods at the exit from the galvanizing bath. The mechanism proposed to explain the origin of the defects was supported by Finite Elements Methods simulations and verified with in-plant tests. The proper countermeasures were then applied and the problem successfully solved.
Gelfi, Marcello; Solazzi, Luigi; Poli, Sandro
2017-01-01
This study is a detailed failure analysis of galvanized high carbon steel wires, which developed coating cracks during the torsion test performed as a quality control at the end of the manufacturing process. Careful visual inspections showed that the cracks are already present in the coating before the torsion test. In order to explain the origin of these cracks, systematic metallographic investigations were performed by means of optical and scanning electron microscope on both the wires and the rods that have been cold drawn to produce the wire. The chemical composition of the galvanized coatings was evaluated by means of energy dispersive spectroscopy. Micro bidimensional X-ray diffraction experiments were also performed to measure the residual stresses in the galvanized coating. The results showed that the failure is related to two main factors: the relatively high content of silicon in the steel and the unsuitable cooling rate of the rods at the exit from the galvanizing bath. The mechanism proposed to explain the origin of the defects was supported by Finite Elements Methods simulations and verified with in-plant tests. The proper countermeasures were then applied and the problem successfully solved. PMID:28772623
Farrow, Lutul D; Parker, Richard D
2010-06-01
Anatomic reconstruction of the anterior cruciate ligament through an accessory medial portal has become increasingly popular. The purpose of this study is to describe the relationship of guide pin exit points to the lateral anatomic structures when preparing the anterior cruciate ligament femoral tunnel through an accessory medial portal. We utilized seven fresh frozen cadaveric knees. Utilizing an anteromedial approach, a guide wire was placed into the center of each bundle's footprint. Each guide wire was advanced through the lateral femoral cortex. The guide pins were passed at 90, 110, and 130 degrees of knee flexion. The distances from each guide pin to the closest relevant structures on the lateral side of the knee were measured. At 90 degrees the posterolateral bundle guide pin was closest to the lateral condyle articular cartilage (mean 5.4 +/- 2.2 mm) and gastrocnemius tendon (mean 5.7 +/- 2.1 mm). At 110 degrees the posterolateral bundle pin was closest to the gastrocnemius tendon (mean 4.5 +/- 3.4 mm). At 130 degrees the posterolateral bundle pin was closest to the gastrocnemius tendon (mean 7.2 +/- 5.5 mm) and lateral collateral ligament (mean 6.8 +/- 2.1 mm). At 90 degrees the anteromedial bundle guide pin was closest to the articular cartilage (mean 2.0 +/- 2.0 mm). At 110 degrees the anteromedial bundle pin was closest to the articular cartilage (mean 7.4 +/- 3.5 mm) and gastrocnemius tendon (mean 12.3 +/- 3.1 mm). At 130 degrees the AM bundle pin was closest to the gastrocnemius tendon (mean 8.2 +/- 3.2 mm) and LCL (mean 15.1 +/- 2.9 mm). Neither guide pin (anteromedial or posterolateral bundle) put the peroneal nerve at risk at any knee flexion angle. At low knee flexion angles the anteromedial and posterolateral bundle guide pins closely approximated multiple lateral structures when using an accessory medial arthroscopic portal. Utilizing higher flexion angles increases the margin of error when preparing both femoral tunnels. During preparation of the anterior cruciate ligament femoral tunnel through an accessory anteromedial portal the tunnels should be drilled in at least 110 degrees of knee flexion in order to move guide pin exit points away from important lateral knee structures.
Rod-like hierarchical Sn/SnOx@C nanostructures with enhanced lithium storage properties
NASA Astrophysics Data System (ADS)
Yang, Juan; Chen, Sanmei; Tang, Jingjing; Tian, Hangyu; Bai, Tao; Zhou, Xiangyang
2018-03-01
Rod-like hierarchical Sn/SnOx@C nanostructures have been designed and synthesized via calcining resorcinol-formaldehyde (RF) resin coated Sn-based metal-organic frameworks. The rod-like hierarchical Sn/SnOx@C nanostructures are made of a great number of carbon-wrapped primary Sn/SnOx nanospheres of 100-200 nm in diameter. The as-prepared hierarchical Sn/SnOx@C nanocomposite manifests a high initial reversible capacity of 1177 mAh g-1 and remains 1001 mAh g-1 after 240 cycles at a current density of 200 mA g-1. It delivers outstanding high-rate performance with a reversible capacity of 823 mAh g-1 even at a high current density of 1000 mA g-1. The enhanced electrochemical performances of the Sn/SnOx@C electrode are mainly attributed to the synergistic effect of the unique hierarchical micro/nanostructures and the protective carbon layer.
Command detector SNR estimator and lock status monitor circuitry
NASA Technical Reports Server (NTRS)
Emerson, R. F.
1976-01-01
A breadboard of the command detector signal-to-noise-ratio estimator and lock status monitor was built on a wire-wrap card. The breadboard was integrated with the standard command detector, and its performance was measured. The design, design constraints, and construction of the breadboard are described. The performance is shown to agree with the theoretical model.
46 CFR 160.015-2 - General requirements for lifeboat winches.
Code of Federal Regulations, 2011 CFR
2011-10-01
... use with gravity davits shall have grooved drums of such size that there will be only one wrap of wire... exposed mechanisms that ice formations may be readily broken adrift when necessary to operate the winch... hand cranks, pay-out wheels, brake levers, etc. (i) Where falls lead along a deck they shall be...
46 CFR 160.015-2 - General requirements for lifeboat winches.
Code of Federal Regulations, 2010 CFR
2010-10-01
... use with gravity davits shall have grooved drums of such size that there will be only one wrap of wire... exposed mechanisms that ice formations may be readily broken adrift when necessary to operate the winch... hand cranks, pay-out wheels, brake levers, etc. (i) Where falls lead along a deck they shall be...
Delamination of Pearlitic Steel Wires: The Defining Role of Prior-Drawing Microstructure
NASA Astrophysics Data System (ADS)
Durgaprasad, A.; Giri, S.; Lenka, S.; Sarkar, Sudip Kumar; Biswas, Aniruddha; Kundu, S.; Mishra, S.; Chandra, S.; Doherty, R. D.; Samajdar, I.
2018-06-01
This article reports the occasional (< 10 pct of the actual production) delamination of pearlitic wires subjected to a drawing strain of 2.5. The original wire rods which exhibited post-drawing delamination had noticeably lower axial alignment of the pearlite: 22 ± 5 pct vs 34 ± 4 pct in the nondelaminated wires. Although all wires had similar through-thickness texture and stress gradients, delaminated wires had stronger gradients in composition and higher hardness across the ferrite-cementite interface. Carbide dissolution and formation of supersaturated ferrite were clearly correlated with delamination, which could be effectively mitigated by controlled laboratory annealing at 673 K. Direct observations on samples subjected to simple shear revealed significant differences in shear localizations. These were controlled by pearlite morphology and interlamellar spacing. Prior-drawing microstructure of coarse misaligned pearlite thus emerged as a critical factor in the wire drawing-induced delamination of the pearlitic wires.
Lunar Module Wiring Design Considerations and Failure Modes
NASA Technical Reports Server (NTRS)
Interbartolo, Michael
2009-01-01
This slide presentation reviews the considerations for the design of wiring for the Lunar Module. Included are a review of the choice of conductors and insulations, the wire splicing (i.e., crimping, and soldering), the wire connectors, and the fabrication of the wire harnesses. The problems in fabrication include the wires being the wrong length, the damage due to the sharp edges, the requried use of temproary protective covers and inadequate training. The problems in the wire harness installation include damge from sharp eges, work on adjacent harnesses, connector damage, and breaking wires. Engineering suggestions from the Apollo-era in reference to the conductors that are reviewed include: the use of plated conductors, and the use of alloys for stronger wiring. In refernce to insulation, the suggestions from Apollo era include the use of polymer tape-wrap wire insulation due to the light weight, however, other types of modern insulation might be more cost-effective. In reference to wire splices and terminal boards the suggestions from the Apollo Era include the use of crimp splices as superior to solder splices, joining multiple wire to a common point using modular plug-ins might be more reliable, but are heavier than crimp splicing. For connectors, the lessons from the Apollo era indicate that a rear environmental seal that does not require additional potting is preferred, and pins should be crimped or welded to the incoming wires and be removable from the rear of the connector.
NASA Technical Reports Server (NTRS)
Ward, Stanley W.
1988-01-01
Thread-mounted thermocouple developed to accurately measure temperature of surrounding material. Comprised of threaded rod or bolt drilled along length, dual-hole ceramic insulator rod, thermocouple wire, optional ceramic filler, and epoxy resin. In contact with and takes average temperature of, surrounding material. Fabricated easily in size and metal to suit particular application. Because of simplicity and ability to measure average temperature, widespread use of design foreseen in varity of applications.
NASA Astrophysics Data System (ADS)
Zeng, Zhengzhong; Ma, Lianying
2004-01-01
A simple and effective bridge-type feeding network consisting only of ordinary resistors and conductive wires is designed and tested which launches a 0.8 ns risetime, 40 ns width, and kV-level rectangular pulse from a coaxial cable onto a rod-shaped resistive high-voltage divider with risetime <2 ns with no significant distortion.
TREAT Neutronics Analysis of Water-Loop Concept Accommodating LWR 9-rod Bundle
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hill, Connie M.; Woolstenhulme, Nicolas E.; Parry, James R.
Abstract. Simulation of a variety of transient conditions has been successfully achieved in the Transient Reactor Test (TREAT) facility during operation between 1959 and 1994 to support characterization and safety analysis of nuclear fuels and materials. A majority of previously conducted tests were focused on supporting sodium-cooled fast reactor (SFR) designs. Experiments evolved in complexity. Simulation of thermal-hydraulic conditions expected to be encountered by fuels and materials in a reactor environment was realized in the development of TREAT sodium loop experiment vehicles. These loops accommodated up to 7-pin fuel bundles and served to simulate more closely the reactor environment whilemore » safely delivering large quantities of energy into the test specimen. Some of the immediate TREAT restart operations will be focused on testing light water reactor (LWR) accident tolerant fuels (ATF). Similar to the sodium loop objectives, a water loop concept, developed and analyzed in the 1990’s, aimed at achieving thermal-hydraulic conditions encountered in commercial power reactors. The historic water loop concept has been analyzed in the context of a reactivity insertion accident (RIA) simulation for high burnup LWR 2-pin and 3-pin fuel bundles. Findings showed sufficient energy could be deposited into the specimens for evaluation. Similar results of experimental feasibility for the water loop concept (past and present) have recently been obtained using MCNP6.1 with ENDF/B-VII.1 nuclear data libraries. The old water loop concept required only two central TREAT core grid spaces. Preparation for future experiments has resulted in a modified water loop conceptual design designated the TREAT water environment recirculating loop (TWERL). The current TWERL design requires nine TREAT core grid spaces in order to place the water recirculating pump under the TREAT core. Due to the effectiveness of water moderation, neutronics analysis shows that removal of seven additional TREAT fuel elements to facilitate the experiment will not inhibit the ability to successfully simulate a RIA for the 2-pin or 3-pin bundle. This new water loop design leaves room for accommodating a larger fuel pin bundle than previously analyzed. The 7-pin fuel bundle in a hexagonal array with similar spacing of fuel pins in a SFR fuel assembly was considered the minimum needed for one central fuel pin to encounter the most correct thermal conditions. The 9-rod fuel bundle in a square array similar in spacing to pins in a LWR fuel assembly would be considered the LWR equivalent. MCNP analysis conducted on a preliminary LWR 9-rod bundle design shows that sufficient energy deposition into the central pin can be achieved well within range to investigate fuel and cladding performance in a simulated RIA. This is achieved by surrounding the flow channel with an additional annulus of water. Findings also show that a highly significant increase in TREAT to specimen power coupling factor (PCF) within the central pin can be achieved by surrounding the experiment with one to two rings of TREAT upgrade fuel assemblies. The experiment design holds promise for the performance evaluation of PWR fuel at extremely high burnup under similar reactor environment conditions.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Thomas, D.G.; Bohanan, R.E.; Clark, D.L.
1978-06-30
The Thermal-Hydraulic Test Facility (THTF) has completed 24 powered rod blowdowns through Mar. 9, 1978. Of these blowdowns, 5 were completed with all 49 rods powered, 2 were completed with 2 inactive rods, and 13 were completed with 4 inactive rods. Initial system pressure was approximately 15.5 MPa (approximately 2250 psi), test section inlet temperature was approximately 559/sup 0/K (approximately 547/sup 0/F), and break area was equivalent to a 200 percent break with the total area usually split between inlet and outlet in the ratio 0.40 : 0.60. Heater rod power was 80, 100, or 122 kW/rod, and the testmore » section outlet temperature was 607/sup 0/K (632/sup 0/F), 598/sup 0/K (617/sup 0/F), or 589/sup 0/K (600/sup 0/F). Mean time to CHF varied from 0.7 to 1.4 sec, with delayed CHF of approximately 2.5 sec occurring in the upper half of the bundle in some tests.« less
NASA Technical Reports Server (NTRS)
1972-01-01
A cost study comparing flat conductor cable (FCC) with small-gage wire (SGW) and conventional round conductor cable (RCC) is presented. This study was based on a vehicle wiring system consisting of 110,000 ft of conventional RCC equally divided between AWG sizes 20,22, and 24 using MIL-W-81044-type wire and MIL-C-26500 circular connectors. Basic cost data were developed on a similar-sized commercial jet airplane wiring system on a previous company R&D program in which advanced wiring techniques were carried through equivalent installations on an airplane mockup; and on data developed on typical average bundles during this program. Various cost elements included were engineering labor, operations (manufacturing) labor, material costs, and cost impact on payload. Engineering labor includes design, wiring system integration, wiring diagrams and cable assembly drawings, wire installations, and other related supporting functions such as the electronic data processing for the wiring. Operations labor includes mockup, tooling and production planning, fabrication, assembly, installation, and quality control cost impact on payload is the conversion of wiring system weight variations through use of different wiring concepts to program payload benefits in terms of dollars.
Direct simulation of heat transfer in a turbulent swept flow over a wire in a channel
NASA Astrophysics Data System (ADS)
Ranjan, Reetesh; Pantano, Carlos; Fischer, Paul; Siegel, Andrew
2009-11-01
We present results from direct numerical simulations of heat transfer (considered as a passive scalar) in a turbulent swept flow across a thin, cylindrical wire in a channel. This model mimics the flow through the wire-wrapped fuel pins typical of fast neutron reactor designs. Mean flow develops both along the wire and across the wire, leading to the formation of a turbulent cross-flow regime in the channel. This leads to improvement in heat transfer properties of the channel surface due to enhancement in mixing. The friction Reynolds number in the axial direction is approximately 305. Cross-flow friction Reynolds numbers ranging from 0 to 115 are examined. Two passive scalars at Prandtl number of 1.0 and 0.01 respectively, are simulated in this study. Constant flux boundary conditions are used along the walls of the channel and adiabatic conditions are used along the surface of the wire. The numerical method uses spectral elements in the plane perpendicular to the wire axis and Fourier decomposition in the direction of the axis of the wire. The simulations use up to 107 million collocation points and were performed at the Argonne Leadership BG/P supercomputer. The passive scalar field statistics are investigated, including mean scalar field, turbulence statistics and instantaneous surface scalar distribution.
Scale factor gage for fiber optics inspection device
NASA Technical Reports Server (NTRS)
Mcmahon, W.; Sugg, F. E.
1971-01-01
Flexible wire device, fastened along outside of fiber bundle from viewing portion to tip, positions calibrated adjustable gage in field of view. Scale factor is determined from known magnification characteristics of fiber optics system or from graduations on gage tip.
Studies on scintillating fiber response
NASA Astrophysics Data System (ADS)
Albers, D.; Bisplinghoff, J.; Bollmann, R.; Büßer, K.; Cloth, P.; Diehl, O.; Dohrmann, F.; Drüke, V.; Engelhardt, H. P.; Ernst, J.; Eversheim, P. D.; Filges, D.; Gasthuber, M.; Gebel, R.; Greiff, J.; Groß, A.; Groß-Hardt, R.; Heine, A.; Heider, S.; Hinterberger, F.; Igelbrink, M.; Jahn, R.; Jeske, M.; Langkau, R.; Lindlein, J.; Maier, R.; Maschuw, R.; Mayer-Kuckuk, T.; Mertler, G.; Metsch, B.; Mosel, F.; Müller, M.; Münstermann, M.; Paetz gen. Schieck, H.; Petry, H. R.; Prasuhn, D.; Rohdjeß, H.; Rosendaal, D.; Roß, U.; von Rossen, P.; Scheid, H.; Schirm, N.; Schulz-Rojahn, M.; Schwandt, F.; Scobel, W.; Steeg, B.; Sterzenbach, G.; Trelle, H. J.; Wellinghausen, A.; Wiedmann, W.; Woller, K.; Ziegler, R.
1996-02-01
Scintillating fibers of type Bicron BCF-12 with 2 × 2 mm 2 cross section, up to 600 mm length, and PMMA cladding have been tested, in conjunction with the multi-channel photomultiplier Hamamatsu R 4760, with minimum ionizing electrons. The impact of cladding, extramural absorbers and/or wrapping on the light attenuation and photoelectron yield is studied in detail. Fibers have been circularly bent with radii of 171 mm and arranged in two layers to bundles forming granulated scintillator rings. Their performance in the EDDA experiment at COSY for detection of high energy protons revealed typically more than 9 (6) photoelectrons per fiber from bundles with (without) mirror on the rear side, guaranteeing detection efficiencies >99% and full compatibility with corresponding solid scintillator rings. The time resolution of 3.4 ns FWHM per fiber read out is essentially due to the R 4760.
Thomas, G.; Ahn, J.H.; Kim, N.J.
1986-10-28
An improved, energy efficient, hot rolling method for direct production of cold formable dual-phase steel is provided. The steel is heated to completely austenitize it and then continuously hot rolled and cooled down into the ferrite-austenite two phase region to a temperature which is just below the effective Ar[sub 3] temperature. The hot rolled steel is then rapidly quenched to provide an alloy containing strong, tough lath martensite (fibers) in a ductile soft ferrite matrix. The method is particularly useful for providing rods in which form the alloy is capable of being drawn into high strength wire or the like in a cold drawing operation without any intermediate annealing or patenting, and has excellent strength, ductility and fatigue characteristics. 3 figs.
Thomas, Gareth; Ahn, Jae-Hwan; Kim, Nack-Joon
1986-01-01
An improved, energy efficient, hot rolling method for direct production of cold formable dual-phase steel is provided. The steel is heated to completely austenitize it and then continuously hot rolled and cooled down into the ferrite-austenite two phase region to a temperature which is just below the effective Ar.sub.3 temperature. The hot rolled steel is then rapidly quenched to provide an alloy containing strong, tough lath martensite (fibers) in a ductile soft ferrite matrix. The method is particularly useful for providing rods in which form the alloy is capable of being drawn into high strength wire or the like in a cold drawing operation without any intermediate annealing or patenting, and has excellent strength, ductility and fatigue characteristics.
Development of a Thin-Film Solar Cell Interconnect for the Powersphere Concept
NASA Technical Reports Server (NTRS)
Simburger, Edward J.; Matsumoto, James H.; Giants, Thomas W.; Garcia, Alexander, III; Liu, Simon; Rawal, Suraj P.; Perry, Alan R.; Marshall, Craig; Lin, John K.; Scarborough, Stephen E.
2005-01-01
Dual junction amorphous silicon (a-Si) solar cells produced on polyimide substrate have been selected as the best candidate to produce a lightweight solar array for the PowerSphere program. The PowerSphere concept features a space-inflatable, geodetic solar array approximately 0.6 meters in diameter and capable of generating about 20W of electrical power. Trade studies of various wiring concepts and connection methods led to an interconnect design with a copper contact that wraps around the edge, to the back of the solar cell. Applying Plasma Vapor Deposited (PVD) copper film to both sides and the edge of the solar cell produces the wrap around contact. This procedure results in a contact pad on the back of the solar cell, which is then laser welded to a flex circuit material. The flex circuit is constructed of copper in a custom designed routing pattern, and then sandwiched in a Kapton insulation layer. The flex circuit then serves as the primary power distribution system between the solar cells and the spacecraft. Flex circuit material is the best candidate for the wiring harness because it allows for low force deployment of the solar cells by the inflatable hinges on the PowerSphere. An additional frame structure, fabricated and assembled by ILC Dover, will reinforce the wrap around contact-flex blanket connection, thus providing a mechanically robust solar cell interconnect for the PowerSphere multifunctional program. The PowerSphere team will use the wraparound contact design approach as the primary solution for solar cell integration and the flex blanket for power distribution.
Comparative range of orthodontic wires.
Ingram, S B; Gipe, D P; Smith, R J
1986-10-01
ADA specification No. 32 for determining the range (elastic limit) of orthodontic wires uses the bending of a wire section treated as a cantilever beam. An alternative method for defining the range of orthodontic wires proposed by Waters (1981) is to wrap wire sections around mandrels of varying diameters and measure the deformation imparted after unwrapping. Four brass mandrels with a total of 46 test diameters ranging from 3.5 to 60.0 mm were used in this study. Wire sections 9 cm in length were rolled on the mandrel with a hand lathe. The mandrel cross section required to produce a predetermined amount of deformation (2 mm arc height for a 5 cm chord) was defined as the yield diameter for that particular wire. No individual wire was tested twice so as to avoid introduction of strain history. Test samples of 488 different orthodontic wires supplied by nine commercial distributors were evaluated (a total of 4,747 samples). Stainless steel wires of identical dimensions had a large variation in range, depending on the state of strain hardening and heat treatment. For example, 0.020 inch round wire had yield diameters ranging from 22.8 mm for Australian special plus orange (TP Laboratories) to 42.9 mm for Nubryte gold (G.A.C. International). Chromium cobalt wires had less range than stainless steel before heat treatment, but increased greatly in range after heat treatment. Nitinol (Unitek) had the greatest range of all wires tested (yield diameter of 8.7 mm for 0.016 inch Nitinol). Multistranded stainless steel wires had yield diameters between 9.0 and 14.0 mm.
Evaluating conducting network based transparent electrodes from geometrical considerations
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kumar, Ankush; Kulkarni, G. U., E-mail: guk@cens.res.in
2016-01-07
Conducting nanowire networks have been developed as viable alternative to existing indium tin oxide based transparent electrode (TE). The nature of electrical conduction and process optimization for electrodes have gained much from the theoretical models based on percolation transport using Monte Carlo approach and applying Kirchhoff's law on individual junctions and loops. While most of the literature work pertaining to theoretical analysis is focussed on networks obtained from conducting rods (mostly considering only junction resistance), hardly any attention has been paid to those made using template based methods, wherein the structure of network is neither similar to network obtained frommore » conducting rods nor similar to well periodic geometry. Here, we have attempted an analytical treatment based on geometrical arguments and applied image analysis on practical networks to gain deeper insight into conducting networked structure particularly in relation to sheet resistance and transmittance. Many literature examples reporting networks with straight or curvilinear wires with distributions in wire width and length have been analysed by treating the networks as two dimensional graphs and evaluating the sheet resistance based on wire density and wire width. The sheet resistance values from our analysis compare well with the experimental values. Our analysis on various examples has revealed that low sheet resistance is achieved with high wire density and compactness with straight rather than curvilinear wires and with narrower wire width distribution. Similarly, higher transmittance for given sheet resistance is possible with narrower wire width but of higher thickness, minimal curvilinearity, and maximum connectivity. For the purpose of evaluating active fraction of the network, the algorithm was made to distinguish and quantify current carrying backbone regions as against regions containing only dangling or isolated wires. The treatment can be helpful in predicting the properties of a network simply from image analysis and will be helpful in improvisation and comparison of various TEs and better understanding of electrical percolation.« less
Evaluating conducting network based transparent electrodes from geometrical considerations
NASA Astrophysics Data System (ADS)
Kumar, Ankush; Kulkarni, G. U.
2016-01-01
Conducting nanowire networks have been developed as viable alternative to existing indium tin oxide based transparent electrode (TE). The nature of electrical conduction and process optimization for electrodes have gained much from the theoretical models based on percolation transport using Monte Carlo approach and applying Kirchhoff's law on individual junctions and loops. While most of the literature work pertaining to theoretical analysis is focussed on networks obtained from conducting rods (mostly considering only junction resistance), hardly any attention has been paid to those made using template based methods, wherein the structure of network is neither similar to network obtained from conducting rods nor similar to well periodic geometry. Here, we have attempted an analytical treatment based on geometrical arguments and applied image analysis on practical networks to gain deeper insight into conducting networked structure particularly in relation to sheet resistance and transmittance. Many literature examples reporting networks with straight or curvilinear wires with distributions in wire width and length have been analysed by treating the networks as two dimensional graphs and evaluating the sheet resistance based on wire density and wire width. The sheet resistance values from our analysis compare well with the experimental values. Our analysis on various examples has revealed that low sheet resistance is achieved with high wire density and compactness with straight rather than curvilinear wires and with narrower wire width distribution. Similarly, higher transmittance for given sheet resistance is possible with narrower wire width but of higher thickness, minimal curvilinearity, and maximum connectivity. For the purpose of evaluating active fraction of the network, the algorithm was made to distinguish and quantify current carrying backbone regions as against regions containing only dangling or isolated wires. The treatment can be helpful in predicting the properties of a network simply from image analysis and will be helpful in improvisation and comparison of various TEs and better understanding of electrical percolation.
NASA Astrophysics Data System (ADS)
Seiler, J. M.; Rameau, B.
Bundle sodium boiling in nominal geometry for different accident conditions is reviewed. Voiding of a subassembly is controlled by not only hydrodynamic effects but mainly by thermal effects. There is a strong influence of the thermal inertia of the bundle material compared to the sodium thermal inertia. Flow instability, during a slow transient, can be analyzed with numerical tools and estimated using simplified approximations. Stable boiling operational conditions under bundle mixed convection (natural convection in the reactor) can be predicted. Voiding during a fast transient can be approximated from single channel calculations. The phenomenology of boiling behavior for a subassembly with inlet completely blocked, submitted to decay heat and lateral cooling; two-phase sodium flow pressure drop in a tube of large hydraulic diameter under adiabatic conditions; critical flow phenomena and voiding rate under high power, slow transient conditions; and onset of dry out under local boiling remains problematical.
High bit rate mass data storage device
NASA Technical Reports Server (NTRS)
1973-01-01
The HDDR-II mass data storage system consists of a Leach MTR 7114 recorder reproducer, a wire wrapped, integrated circuit flat plane and necessary power supplies for the flat plane. These units, with interconnecting cables and control panel are enclosed in a common housing mounted on casters. The electronics used in the HDDR-II double density decoding and encoding techniques are described.
Static Dissipative Cable Ties, Such as for Radiation Belt Storm Probes
NASA Technical Reports Server (NTRS)
Langley, Patrick T. (Inventor); Siddique, Fazle E. (Inventor)
2015-01-01
An article, such as, but not limited to, a cable strap to wrap, support, or secure one or more wires or cables, is formed by cyclically heating and cooling and/or irradiating an article formed of a static dissipative ethylene tetrafluoroethylen (ETFE) resin, to reduce an electrical resistivity and/or to increase a tensile strength of the article.
Formation of Sub-Millimeter-Size Powerful X-Ray Sources in Low-Impedance Rod-Pinch Diodes
NASA Astrophysics Data System (ADS)
Sorokin, S. A.
2018-01-01
In the paper, experiments on the formation of a low-impedance diode and a focused electron beam as a result of detachment of radial wires, accelerated by the current of a high-current generator, from the rod anode have been described. In the experiments, along with studies of conditions for compact focusing of the electron beam and effective generation of hard x-rays, the shape of the tip of the anode rod is determined at which the x-ray source is point-sized when viewed in the radial direction.
Wire metamaterials: physics and applications.
Simovski, Constantin R; Belov, Pavel A; Atrashchenko, Alexander V; Kivshar, Yuri S
2012-08-16
The physics and applications of a broad class of artificial electromagnetic materials composed of lattices of aligned metal rods embedded in a dielectric matrix are reviewed. Such structures are here termed wire metamaterials. They appear in various settings and can operate from microwaves to THz and optical frequencies. An important group of these metamaterials is a wire medium possessing extreme optical anisotropy. The study of wire metamaterials has a long history, however, most of their important and useful properties have been revealed and understood only recently, especially in the THz and optical frequency ranges where the wire media correspond to the lattices of microwires and nanowires, respectively. Another group of wire metamaterials are arrays and lattices of nanorods of noble metals whose unusual properties are driven by plasmonic resonances. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
The Integrity bare-metal stent made by continuous sinusoid technology.
Turco, Mark A
2011-05-01
The Integrity Coronary Stent System (Medtronic Vascular, CA, USA) is a low-profile, open-cell, cobalt-chromium-alloy advanced bare-metal iteration of the well-known Driver/Micro-Driver Coronary Stent System (Medtronic Vascular). The Integrity stent is made with a process called continuous sinusoid technology. This process allows stent construction via wrapping a single thin strand of wire around a mandrel in a sinusoid configuration, with laser fusion of adjacent crowns. The wire-forming process and fusion pattern provide the stent with a continuous preferential bending plane, intended to allow easier access to, and smoother tracking within, distal and tortuous vessels while radial strength is maintained. Continuous sinusoid technology represents innovation in the design of stent platforms and will provide a future stent platform for newer technology, including drug-eluting stent platforms, drug-filled stents and core wire stents.
A-15 Superconducting composite wires and a method for making
Suenaga, Masaki; Klamut, Carl J.; Luhman, Thomas S.
1984-01-01
A method for fabricating superconducting wires wherein a billet of copper containing filaments of niobium or vanadium is rolled to form a strip which is wrapped about a tin-alloy core to form a composite. The alloy is a tin-copper alloy for niobium filaments and a gallium-copper alloy for vanadium filaments. The composite is then drawn down to a desired wire size and heat treated. During the heat treatment process, the tin in the bronze reacts with the niobium to form the superconductor niobium tin. In the case where vanadium is used, the gallium in the gallium bronze reacts with the vanadium to form the superconductor vanadium gallium. This new process eliminates the costly annealing steps, external tin plating and drilling of bronze ingots required in a number of prior art processes.
NASA Technical Reports Server (NTRS)
Szatkowski, G. P.
1983-01-01
A computer simulation system has been developed for the Space Shuttle's advanced Centaur liquid fuel booster rocket, in order to conduct systems safety verification and flight operations training. This simulation utility is designed to analyze functional system behavior by integrating control avionics with mechanical and fluid elements, and is able to emulate any system operation, from simple relay logic to complex VLSI components, with wire-by-wire detail. A novel graphics data entry system offers a pseudo-wire wrap data base that can be easily updated. Visual subsystem operations can be selected and displayed in color on a six-monitor graphics processor. System timing and fault verification analyses are conducted by injecting component fault modes and min/max timing delays, and then observing system operation through a red line monitor.
Scalable Nernst thermoelectric power using a coiled galfenol wire
NASA Astrophysics Data System (ADS)
Yang, Zihao; Codecido, Emilio A.; Marquez, Jason; Zheng, Yuanhua; Heremans, Joseph P.; Myers, Roberto C.
2017-09-01
The Nernst thermopower usually is considered far too weak in most metals for waste heat recovery. However, its transverse orientation gives it an advantage over the Seebeck effect on non-flat surfaces. Here, we experimentally demonstrate the scalable generation of a Nernst voltage in an air-cooled metal wire coiled around a hot cylinder. In this geometry, a radial temperature gradient generates an azimuthal electric field in the coil. A Galfenol (Fe0.85Ga0.15) wire is wrapped around a cartridge heater, and the voltage drop across the wire is measured as a function of axial magnetic field. As expected, the Nernst voltage scales linearly with the length of the wire. Based on heat conduction and fluid dynamic equations, finite-element method is used to calculate the temperature gradient across the Galfenol wire and determine the Nernst coefficient. A giant Nernst coefficient of -2.6 μV/KT at room temperature is estimated, in agreement with measurements on bulk Galfenol. We expect that the giant Nernst effect in Galfenol arises from its magnetostriction, presumably through enhanced magnon-phonon coupling. Our results demonstrate the feasibility of a transverse thermoelectric generator capable of scalable output power from non-flat heat sources.
NASA Technical Reports Server (NTRS)
Carroll, Joseph A.; Alexander, Charles M.
1993-01-01
Design concept promises speed, control, and reliability. Scheme for deploying tether provides for fast, free, and snagless payout and fast, dependable braking. Developed for small, expendable tethers in outer space, scheme also useful in laying transoceanic cables, deploying guidance wires to torpedoes and missiles, paying out rescue lines from ship to ship via rockets, deploying antenna wires, releasing communication and power cables to sonobuoys and expendable bathythermographs, and in reeling out lines from fishing rods.
Magnetic antenna using metallic glass
NASA Technical Reports Server (NTRS)
Desch, Michael D. (Inventor); Farrell, William M. (Inventor); Houser, Jeffrey G. (Inventor)
1996-01-01
A lightweight search-coil antenna or sensor assembly for detecting magnetic fields and including a multi-turn electromagnetic induction coil wound on a spool type coil form through which is inserted an elongated coil loading member comprised of metallic glass material wrapped around a dielectric rod. The dielectric rod consists of a plastic or a wooden dowel having a length which is relatively larger than its thickness so as to provide a large length-to-diameter ratio. A tri-axial configuration includes a housing in which is located three substantially identical mutually orthogonal electromagnetic induction coil assemblies of the type described above wherein each of the assemblies include an electromagnetic coil wound on a dielectric spool with an elongated metallic glass coil loading member projecting therethrough.
Hayashi, A
1991-02-01
The present experimental study was undertaken to evaluate the efficacy of combined latissimus dorsi muscle flap and soft Marlex mesh in the reconstruction of the trachea. Thirty-one mongrel dogs underwent a two-stage operation. In the first stage operation, they were divided into four groups for implanting a different prosthesis. A silicone rod was used as the core and this was rolled with soft Marlex mesh to make a prosthesis (Group A and B: without reinforce, Group C: reinforced by wrapping stainless steel mesh, Group D: reinforced with helical stain steel wire). The latissimus dorsi muscle flap was rolled circumferentially around the prosthesis and it was left in place for a period of 4 to 6 weeks. In the second stage operation, the long pedicled muscle flap with the biologically organized prosthesis was mobilized to be guided into the cervix, and the tracheal reconstruction was done with them following circumferential tracheal resection. In result, five of six dogs of group D survived more than 6 months after the replacement without anastomotic leakage or stenosis causing inflammatory granulation. Organization with neo-vascularity of the prosthesis at the time of the tracheal reconstruction was important firstly to avoid incurring complications concerning anastomosis and secondly for long-term stability of the healing and epithelialization of the prosthesis.
Danson, Edward J; Ward, Michael
2015-06-01
We present a case of a 58-year-old woman with diabetes mellitus with a history of angina, coronary artery bypass 24 years previously and who underwent retrieval of a fractured coronary buddy wire from the right brachial artery following attempted coronary intervention to a saphenous vein graft via the right radial route. Attempted removal of the guide wire had caused guide catheter-induced dissection of the vein graft in addition to a distal stent edge dissection before fracture in the brachial artery. The fractured end of the buddy wire was found to be in the subintimal space and could only be retrieved by advancing the wire into the subclavian artery by means of wrapping its free portion around the guiding catheter. Its fractured end could then be snared into the guiding catheter but could only be withdrawn from behind the stented segment in the vein graft by means of a trap balloon in the guiding catheter. Successful stenting of a guide catheter-induced dissection and distal stent edge dissection within the vein graft was then performed. This case highlights the hazards of deploying stents over buddy wires and of fractured guide wires in coronary intervention. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.
2014-08-01
installing high-capacity, post-tensioned foundation anchors. These stressed steel tendons have been used to strengthen hydraulic concrete structures and to...Field Inspection in Mass Concrete .................................... 32 3.3 NDT Technologies in General for Seven Strand Wire Cable Inspection...rod end of a 1.31-inch-diameter grease embedded trunion anchor rod with concrete termination. ..................... 37 Figure 32. 441 Khz narrow
NASA Astrophysics Data System (ADS)
Jordan, Jared Williams; Dvorak, Steven L.; Sternberg, Ben K.
2010-10-01
In this paper, we develop a technique for designing high-power, non-linear, transmitting rod-core antennas by using simple modified scale factors rather than running labor-intensive numerical models. By using modified scale factors, a designer can predict changes in magnetic moment, inductance, core series loss resistance, etc. We define modified scale factors as the case when all physical dimensions of the rod antenna are scaled by p, except for the cross-sectional area of the individual wires or strips that are used to construct the core. This allows one to make measurements on a scaled-down version of the rod antenna using the same core material that will be used in the final antenna design. The modified scale factors were derived from prolate spheroidal analytical expressions for a finite-length rod antenna and were verified with experimental results. The modified scaling factors can only be used if the magnetic flux densities within the two scaled cores are the same. With the magnetic flux density constant, the two scaled cores will operate with the same complex permeability, thus changing the non-linear problem to a quasi-linear problem. We also demonstrate that by holding the number of turns times the drive current constant, while changing the number of turns, the inductance and core series loss resistance change by the number of turns squared. Experimental measurements were made on rod cores made from varying diameters of black oxide, low carbon steel wires and different widths of Metglas foil. Furthermore, we demonstrate that the modified scale factors work even in the presence of eddy currents within the core material.
Sperm bundle and reproductive organs of carabid beetles tribe Pterostichini (Coleoptera: Carabidae)
NASA Astrophysics Data System (ADS)
Sasakawa, Kôji
2007-05-01
The morphological characteristics of sperm and reproductive organs may offer clues as to how reproductive systems have evolved. In this paper, the morphologies of the sperm and male reproductive organs of carabid beetles in the tribe Pterostichini (Coleoptera: Carabidae) are described, and the morphological associations among characters are examined. All species form sperm bundles in which the head of the sperm was embedded in a rod-shaped structure, i.e., spermatodesm. The spermatodesm shape (left-handed spiral, right-handed spiral, or without conspicuous spiral structure) and the condition of the sperm on the spermatodesm surface (with the tail free-moving or forming a thin, sheetlike structure) vary among species. In all species, the spiral directions of the convoluted seminal vesicles and vasa deferentia are the same on both sides of the body; that is, they show an asymmetric structure. The species in which the sperm bundle and the seminal vesicles both have a spiral structure could be classified into two types, with significant differences in sperm-bundle length between the two types. The species with a sperm-bundle spiral and seminal-vesicle spiral of almost the same diameter have longer sperm bundles than the species with a sperm-bundle spiral and seminal-vesicle tube of almost the same diameter. In the former type, the spiral directions of the sperm bundles and seminal vesicles are inevitably the same, whereas they differ in some species with the later type. Therefore, increased sperm bundle length appears to have been facilitated by the concordance of the sperm bundle’s coiling direction with the coiling direction of the seminal vesicle.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chen, B.C.J.; Sha, W.T.; Doria, M.L.
1980-11-01
The governing equations, i.e., conservation equations for mass, momentum, and energy, are solved as a boundary-value problem in space and an initial-value problem in time. BODYFIT-1FE code uses the technique of boundary-fitted coordinate systems where all the physical boundaries are transformed to be coincident with constant coordinate lines in the transformed space. By using this technique, one can prescribe boundary conditions accurately without interpolation. The transformed governing equations in terms of the boundary-fitted coordinates are then solved by using implicit cell-by-cell procedure with a choice of either central or upwind convective derivatives. It is a true benchmark rod-bundle code withoutmore » invoking any assumptions in the case of laminar flow. However, for turbulent flow, some empiricism must be employed due to the closure problem of turbulence modeling. The detailed velocity and temperature distributions calculated from the code can be used to benchmark and calibrate empirical coefficients employed in subchannel codes and porous-medium analyses.« less
Functionalization of quantum rods with oligonucleotides for programmable assembly with DNA origami
NASA Astrophysics Data System (ADS)
Doane, Tennyson L.; Alam, Rabeka; Maye, Mathew M.
2015-02-01
The DNA-mediated self-assembly of CdSe/CdS quantum rods (QRs) onto DNA origami is described. Two QR types with unique optical emission and high polarization were synthesized, and then functionalized with oligonucleotides (ssDNA) using a novel protection-deprotection approach, which harnessed ssDNA's tailorable rigidity and denaturation temperature to increase DNA coverage by reducing non-specific coordination and wrapping. The QR assembly was programmable, and occurred at two different assembly zones that had capture strands in parallel alignment. QRs with different optical properties were assembled, opening up future studies on orientation dependent QR FRET. The QR-origami conjugates could be purified via gel electrophoresis and sucrose gradient ultracentrifugation. Assembly yields, QR stoichiometry and orientation, as well as energy transfer implications were studied in light of QR distances, origami flexibility, and conditions.The DNA-mediated self-assembly of CdSe/CdS quantum rods (QRs) onto DNA origami is described. Two QR types with unique optical emission and high polarization were synthesized, and then functionalized with oligonucleotides (ssDNA) using a novel protection-deprotection approach, which harnessed ssDNA's tailorable rigidity and denaturation temperature to increase DNA coverage by reducing non-specific coordination and wrapping. The QR assembly was programmable, and occurred at two different assembly zones that had capture strands in parallel alignment. QRs with different optical properties were assembled, opening up future studies on orientation dependent QR FRET. The QR-origami conjugates could be purified via gel electrophoresis and sucrose gradient ultracentrifugation. Assembly yields, QR stoichiometry and orientation, as well as energy transfer implications were studied in light of QR distances, origami flexibility, and conditions. Electronic supplementary information (ESI) available: Experimental conditions, DNA origami blueprint and sequences, FRET calculations. Additional Fig. S1-S13. See DOI: 10.1039/c4nr07662a
40 CFR 420.85 - Pretreatment standards for existing sources (PSES).
Code of Federal Regulations, 2010 CFR
2010-07-01
...) EFFLUENT GUIDELINES AND STANDARDS IRON AND STEEL MANUFACTURING POINT SOURCE CATEGORY Salt Bath Descaling... Nickel 0.00263 0.000876 (2) Batch, rod and wire. Subpart H Pollutant or pollutant property Pretreatment...
40 CFR 420.85 - Pretreatment standards for existing sources (PSES).
Code of Federal Regulations, 2011 CFR
2011-07-01
...) EFFLUENT GUIDELINES AND STANDARDS IRON AND STEEL MANUFACTURING POINT SOURCE CATEGORY Salt Bath Descaling... Nickel 0.00263 0.000876 (2) Batch, rod and wire. Subpart H Pollutant or pollutant property Pretreatment...
49 CFR 571.139 - Standard No. 139; New pneumatic radial tires for light vehicles.
Code of Federal Regulations, 2014 CFR
2014-10-01
... part of the tire that is made of steel wires, wrapped or reinforced by ply cords and that is shaped to... mechanical device made of rubber, chemicals, fabric and steel or other materials, that, when mounted on an....Test sample. For the tests specified in S6, use: (a) One tire for high speed; (b) Another tire for...
49 CFR 571.139 - Standard No. 139; New pneumatic radial tires for light vehicles.
Code of Federal Regulations, 2013 CFR
2013-10-01
... part of the tire that is made of steel wires, wrapped or reinforced by ply cords and that is shaped to... mechanical device made of rubber, chemicals, fabric and steel or other materials, that, when mounted on an....Test sample. For the tests specified in S6, use: (a) One tire for high speed; (b) Another tire for...
49 CFR 571.139 - Standard No. 139; New pneumatic radial tires for light vehicles.
Code of Federal Regulations, 2012 CFR
2012-10-01
... part of the tire that is made of steel wires, wrapped or reinforced by ply cords and that is shaped to... mechanical device made of rubber, chemicals, fabric and steel or other materials, that, when mounted on an....Test sample. For the tests specified in S6, use: (a) One tire for high speed; (b) Another tire for...
49 CFR 571.109 - Standard No. 109; New pneumatic and certain specialty tires.
Code of Federal Regulations, 2011 CFR
2011-10-01
... of the tire made of steel wires, wrapped or reinforced by ply cords, that is shaped to fit the rim... pressure; (c) Maximum load rating; (d) The generic name of each cord material used in the plies (both... plies in the tread area if different; (f) The words “tubeless” or “tube type” as applicable; and (g) The...
49 CFR 571.109 - Standard No. 109; New pneumatic and certain specialty tires.
Code of Federal Regulations, 2010 CFR
2010-10-01
... of the tire made of steel wires, wrapped or reinforced by ply cords, that is shaped to fit the rim... pressure; (c) Maximum load rating; (d) The generic name of each cord material used in the plies (both... plies in the tread area if different; (f) The words “tubeless” or “tube type” as applicable; and (g) The...
X-ray measurements of the strain and shape of dielectric/metallic wrap-gated InAs nanowires
NASA Astrophysics Data System (ADS)
Eymery, J.; Favre-Nicolin, V.; Fröberg, L.; Samuelson, L.
2009-03-01
Wrap-gate (111) InAs nanowires (NWs) were studied after HfO2 dielectric coating and Cr metallic deposition by a combination of grazing incidence x-ray techniques. In-plane and out-of-plane x-ray diffraction (crystal truncation rod analysis) allow determining the strain tensor. The longitudinal contraction, increasing with HfO2 and Cr deposition, is significantly larger than the radial dilatation. For the Cr coating, the contraction along the growth axis is quite large (-0.95%), and the longitudinal/radial deformation ratio is >10, which may play a role on the NW transport properties. Small angle x-ray scattering shows a smoothening of the initial hexagonal bare InAs NW shape and gives the respective core/shell thicknesses, which are compared to flat surface values.
NASA Astrophysics Data System (ADS)
Walsh, M.
1984-05-01
This research demonstrated the feasibility of supplying approximately 1 watt of electrical power for one year on the sea bed with a novel battery, the rope battery. The proposed battery would look very much like a small diameter wire rope, possibly hundreds of feet long. This unusual shape permits the rope battery to take full advantage of the vastness of the ocean floor and permits at great pressure the steady diffusion of reaction products away from the battery itself. A sea water battery is described consisting of an inner bundle of coated wires which slowly corrode and an outer layer of fine wires which simultaneously provides strength, armor and surface area for slow hydrogen evolution. Two variations are examined. The fuse utilizes magnesium wires and burns slowly from the end. The rope utilizes lithium-zinc alloys and is slowly consumed along its entire length.
Cathode degradation and erosion in high pressure arc discharges
NASA Technical Reports Server (NTRS)
Hardy, T. L.; Nakanishi, S.
1984-01-01
The various processes which control cathode erosion and degradation were identified and evaluated. A direct current arc discharge was established between electrodes in a pressure-controlled gas flow environment. The cathode holder was designed for easy testing of various cathode materials. The anode was a water cooled copper collector electrode. The arc was powered by a dc power supply with current and voltage regulated cross-over control. Nitrogen and argon were used as propellants and the materials used were two percent thoriated tungsten, barium oxide impregnated porous tungsten, pure tungsten and lanthanum hexaboride. The configurations used were cylindrical solid rods, wire bundles supported by hollow molybdenum tubes, cylindrical hollow tubes, and hollow cathodes of the type used in ion thrusters. The results of the mass loss tests in nitrogen indicated that pure tungsten eroded at a rate more than 10 times faster than the rates of the impregnated tungsten materials. It was found that oxygen impurities of less than 0.5 percent in the nitrogen increased the mass loss rate by a factor of 4 over high purity nitrogen. At power levels less than 1 kW, cathode size and current level did not significantly affect the mass loss rate. The hollow cathode was found to be operable in argon and in nitrogen only at pressures below 400 and 200 torr, respectively.
2011-09-01
Testing Input electrodes consisting of 1/2” diameter, 6” long copper rods were wired to separate conductors of a shielded, commercially available...underwater-rated electrical cable (three-conductor, shielded, shipboard cable (TSS-2), 18 American Wire Gauge (AWG) stranded copper ). Electrode pairs...sandpaper prior to use to ensure the best electrical continuity between the water and electrode by removing any copper oxide. This electrode
Fabrication and evaluation of low fiber content alumina fiber/aluminum composites
NASA Technical Reports Server (NTRS)
Hack, J. E.; Strempek, G. C.
1980-01-01
The mechanical fabrication of low volume percent fiber, polycrystalline alumina fiber reinforced aluminum composites was accomplished. Wire preform material was prepared by liquid-metal infiltration of alumina fiber bundles. The wires were subsequently encapsulated with aluminum foil and fabricated into bulk composite material by hot-drawing. Extensive mechanical, thermal and chemical testing was conducted on preform and bulk material to develop a process and material data base. In addition, a preliminary investigation of mechanical forming of bulk alumina fiber reinforced aluminum composite material was conducted.
Development of burnup dependent fuel rod model in COBRA-TF
NASA Astrophysics Data System (ADS)
Yilmaz, Mine Ozdemir
The purpose of this research was to develop a burnup dependent fuel thermal conductivity model within Pennsylvania State University, Reactor Dynamics and Fuel Management Group (RDFMG) version of the subchannel thermal-hydraulics code COBRA-TF (CTF). The model takes into account first, the degradation of fuel thermal conductivity with high burnup; and second, the fuel thermal conductivity dependence on the Gadolinium content for both UO2 and MOX fuel rods. The modified Nuclear Fuel Industries (NFI) model for UO2 fuel rods and Duriez/Modified NFI Model for MOX fuel rods were incorporated into CTF and fuel centerline predictions were compared against Halden experimental test data and FRAPCON-3.4 predictions to validate the burnup dependent fuel thermal conductivity model in CTF. Experimental test cases from Halden reactor fuel rods for UO2 fuel rods at Beginning of Life (BOL), through lifetime without Gd2O3 and through lifetime with Gd 2O3 and a MOX fuel rod were simulated with CTF. Since test fuel rod and FRAPCON-3.4 results were based on single rod measurements, CTF was run for a single fuel rod surrounded with a single channel configuration. Input decks for CTF were developed for one fuel rod located at the center of a subchannel (rod-centered subchannel approach). Fuel centerline temperatures predicted by CTF were compared against the measurements from Halden experimental test data and the predictions from FRAPCON-3.4. After implementing the new fuel thermal conductivity model in CTF and validating the model with experimental data, CTF model was applied to steady state and transient calculations. 4x4 PWR fuel bundle configuration from Purdue MOX benchmark was used to apply the new model for steady state and transient calculations. First, one of each high burnup UO2 and MOX fuel rods from 4x4 matrix were selected to carry out single fuel rod calculations and fuel centerline temperatures predicted by CTF/TORT-TD were compared against CTF /TORT-TD /FRAPTRAN predictions. After confirming that the new fuel thermal conductivity model in CTF worked and provided consistent results with FRAPTRAN predictions for a single fuel rod configuration, the same type of analysis was carried out for a bigger system which is the 4x4 PWR bundle consisting of 15 fuel pins and one control guide tube. Steady- state calculations at Hot Full Power (HFP) conditions for control guide tube out (unrodded) were performed using the 4x4 PWR array with CTF/TORT-TD coupled code system. Fuel centerline, surface and average temperatures predicted by CTF/TORT-TD with and without the new fuel thermal conductivity model were compared against CTF/TORT-TD/FRAPTRAN predictions to demonstrate the improvement in fuel centerline predictions when new model was used. In addition to that constant and CTF dynamic gap conductance model were used with the new thermal conductivity model to show the performance of the CTF dynamic gap conductance model and its impact on fuel centerline and surface temperatures. Finally, a Rod Ejection Accident (REA) scenario using the same 4x4 PWR array was run both at Hot Zero Power (HZP) and Hot Full Power (HFP) condition, starting at a position where half of the control rod is inserted. This scenario was run using CTF/TORT-TD coupled code system with and without the new fuel thermal conductivity model. The purpose of this transient analysis was to show the impact of thermal conductivity degradation (TCD) on feedback effects, specifically Doppler Reactivity Coefficient (DRC) and, eventually, total core reactivity.
An electrode to record the mouse cornea electroretinogram.
Goto, Y
The mouse has become a popular model for the study of retinal degeneration, but an electrode suitable for recording electroretinograms from the mouse cornea is not available commercially. I developed a simple electrode suitable for the relatively small mouse eye by attaching a thin stainless-steel wire through the barrel of a 1-cc syringe. The end of the wire is formed into a coil by wrapping it around a 0.5- or 1.0-mm pin. The syringe barrel serves as a convenient way to hold the electrode in a goose-neck holder. This electrode has been used successfully to obtain electroretinograms from hundreds of mice as young as 14 days.
Klimo, Paul; Astur, Nelson; Gabrick, Kyle; Warner, William C; Muhlbauer, Michael S
2013-02-01
Many methods to stabilize and fuse the craniocervical junction have been described. One of the early designs was a contoured (Luque) rod fixated with wires, the so-called Hartshill-Ransford loop. In this study, the authors report their 20-year experience with this surgical technique in children. The authors reviewed the medical records of patients 18 years of age or younger who underwent dorsal occipitocervical fusion procedures between March 1992 and March 2012 at Le Bonheur Children's Hospital using a contoured rod and wire construct. Data on basic patient characteristics, causes of instability, neurological function at presentation and at last follow-up, details of surgery, complications, and radiographic outcome were collected. Twenty patients (11 male) were identified, with a mean age of 5.5 years (range 1-18 years) and a median follow-up of 43.5 months. Fourteen patients had atlantooccipital dislocation, 2 patients had atlantoaxial fracture-dissociations, 2 had Down syndrome with occipitocervical and atlantoaxial instability, 1 had an epithelioid sarcoma from the clivus to C-2, and 1 had an anomalous atlas with resultant occipitocervical instability. Surgical stabilization extended from the occiput to C-1 in 3 patients, C-2 in 6, C-3 in 8, and to C-4 in 3. Bone morphogenetic protein was used in 2 patients. Two patients were placed in a halo orthosis; the rest were kept in a hard collar for 6-8 weeks. All patients were neurologically stable after surgery. One patient with a dural tear experienced wound dehiscence with CSF leakage and required reoperation. Eighteen patients went on to achieve fusion within 6 months of surgery; 1 patient was initially lost to follow-up, but recent imaging demonstrated a solid fusion. There were no early hardware or bone failures requiring hardware removal, but radiographs obtained 8 years after surgery showed that 1 patient had an asymptomatic fractured rod. There were no instances of symptomatic junctional degeneration, and no patient was found to have increasing lordosis over the fused segments. Five (31%) of the 16 trauma patients required a shunt for hydrocephalus. Despite the proliferation of screw-fixation techniques for craniocervical instability in children, the contoured rod-wire construct remains an effective, less expensive, and technically easier alternative that has been in use for almost 30 years. It confers immediate stability, and therefore most patients will not need to be placed in a halo device postoperatively. A secondary observation in our series was the high (30%) rate of hydrocephalus requiring a shunt in patients with traumatic instability.
Demonstration of Scalable Nernst Voltage in a Coiled Galfenol Wire
NASA Astrophysics Data System (ADS)
Codecido, Emilio; Yang, Zihao; Marquez, Jason; Zheng, Yuanhua; Heremans, Joseph; Myers, Roberto
Transverse thermopower by the Nernst effect is usually considered far too weak an effect for waste heat recovery and power generation. We propose that magnetostriction provides a pathway to enhance the Nernst effect because it increases phonon and magnon coupling. Here, we measure the Nernst coefficient in the magnetostrictive alloy, Galfenol (Fe0.85Ga0.15) and observe an extraordinarily large Nernst coefficient at room temperature of 4 μV/KT. Next we demonstrate a new geometry for efficient and low cost power generation by wrapping Galfenol wire around a hot cylinder. This coil geometry results in a radial temperature gradient direction. With a magnetic field applied in the axial direction, a uniform Nernst electric field is produced along the azimuthal direction at every point along the coil. As a result of this geometry, the Nernst voltage is shown to increase linearly with wire length, proving the concept of scalable Nernst thermal power generation.
Connectedness percolation of hard deformed rods
NASA Astrophysics Data System (ADS)
Drwenski, Tara; Dussi, Simone; Dijkstra, Marjolein; van Roij, René; van der Schoot, Paul
2017-12-01
Nanofiller particles, such as carbon nanotubes or metal wires, are used in functional polymer composites to make them conduct electricity. They are often not perfectly straight cylinders but may be tortuous or exhibit kinks. Therefore we investigate the effect of shape deformations of the rod-like nanofillers on the geometric percolation threshold of the dispersion. We do this by using connectedness percolation theory within a Parsons-Lee type of approximation, in combination with Monte Carlo integration for the average overlap volume in the isotropic fluid phase. We find that a deviation from a perfect rod-like shape has very little effect on the percolation threshold, unless the particles are strongly deformed. This demonstrates that idealized rod models are useful even for nanofillers that superficially seem imperfect. In addition, we show that for small or moderate rod deformations, the universal scaling of the percolation threshold is only weakly affected by the precise particle shape.
Development of fast cooling pulsed magnets at the Wuhan National High Magnetic Field Center.
Peng, Tao; Sun, Quqin; Zhao, Jianlong; Jiang, Fan; Li, Liang; Xu, Qiang; Herlach, Fritz
2013-12-01
Pulsed magnets with fast cooling channels have been developed at the Wuhan National High Magnetic Field Center. Between the inner and outer sections of a coil wound with a continuous length of CuNb wire, G10 rods with cross section 4 mm × 5 mm were inserted as spacers around the entire circumference, parallel to the coil axis. The free space between adjacent rods is 6 mm. The liquid nitrogen flows freely in the channels between these rods, and in the direction perpendicular to the rods through grooves provided in the rods. For a typical 60 T pulsed magnetic field with pulse duration of 40 ms, the cooling time between subsequent pulses is reduced from 160 min to 35 min. Subsequently, the same technology was applied to a 50 T magnet with 300 ms pulse duration. The cooling time of this magnet was reduced from 480 min to 65 min.
Miyazaki, Taisuke; Yamasaki, Miwako; Hashimoto, Kouichi; Kohda, Kazuhisa; Yuzaki, Michisuke; Shimamoto, Keiko; Tanaka, Kohichi; Kano, Masanobu; Watanabe, Masahiko
2017-01-01
Astrocytes regulate synaptic transmission through controlling neurotransmitter concentrations around synapses. Little is known, however, about their roles in neural circuit development. Here we report that Bergmann glia (BG), specialized cerebellar astrocytes that thoroughly enwrap Purkinje cells (PCs), are essential for synaptic organization in PCs through the action of the l-glutamate/l-aspartate transporter (GLAST). In GLAST-knockout mice, dendritic innervation by the main ascending climbing fiber (CF) branch was significantly weakened, whereas the transverse branch, which is thin and nonsynaptogenic in control mice, was transformed into thick and synaptogenic branches. Both types of CF branches frequently produced aberrant wiring to proximal and distal dendrites, causing multiple CF–PC innervation. Our electrophysiological analysis revealed that slow and small CF-evoked excitatory postsynaptic currents (EPSCs) were recorded from almost all PCs in GLAST-knockout mice. These atypical CF-EPSCs were far more numerous and had significantly faster 10–90% rise time than those elicited by glutamate spillover under pharmacological blockade of glial glutamate transporters. Innervation by parallel fibers (PFs) was also affected. PF synapses were robustly increased in the entire dendritic trees, leading to impaired segregation of CF and PF territories. Furthermore, lamellate BG processes were retracted from PC dendrites and synapses, leading to the exposure of these neuronal elements to the extracellular milieus. These synaptic and glial phenotypes were reproduced in wild-type mice after functional blockade of glial glutamate transporters. These findings highlight that glutamate transporter function by GLAST on BG plays important roles in development and maintenance of proper synaptic wiring and wrapping in PCs. PMID:28655840
Recent GE BWR fuel experience and design evolution
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wood, J.E.; Potts, G.A.; Proebstle, R.A.
1992-01-01
Reliable fuel operation is essential to the safe, reliable, and economic power production by today's commercial nuclear reactors. GE Nuclear Energy is committed to maximize fuel reliability through the progressive development of improved fuel design features and dedication to provide the maximum quality of the design features and dedication to provide the maximum quality of the design, fabrication, and operation of GE BWR fuel. Over the last 35 years, GE has designed, fabricated, and placed in operation over 82,000 BWR fuel bundles containing over 5 million fuel rods. This experience includes successful commercial reactor operation of fuel assemblies to greatermore » than 45000 MWd/MTU bundle average exposure. This paper reports that this extensive experience base has enabled clear identification and characterization of the active failure mechanisms. With this failure mechanism characterization, mitigating actions have been developed and implemented by GE to provide the highest reliability BWR fuel bundles possible.« less
The counterbend phenomenon in flagellar axonemes and cross-linked filament bundles
Gadêlha, Hermes; Gaffney, Eamonn A.; Goriely, Alain
2013-01-01
Recent observations of flagellar counterbend in sea urchin sperm show that the mechanical induction of curvature in one part of a passive flagellum induces a compensatory countercurvature elsewhere. This apparent paradoxical effect cannot be explained using the standard elastic rod theory of Euler and Bernoulli, or even the more general Cosserat theory of rods. Here, we develop a geometrically exact mechanical model to describe the statics of microtubule bundles that is capable of predicting the curvature reversal events observed in eukaryotic flagella. This is achieved by allowing the interaction of deformations in different material directions, by accounting not only for structural bending, but also for the elastic forces originating from the internal cross-linking mechanics. Large-amplitude static configurations can be described analytically, and an excellent match between the model and the observed counterbend deformation was found. This allowed a simultaneous estimation of multiple sperm flagellum material parameters, namely the cross-linking sliding resistance, the bending stiffness, and the sperm head junction compliance ratio. We further show that small variations on the empirical conditions may induce discrepancies for the evaluation of the flagellar material quantities, so that caution is required when interpreting experiments. Finally, our analysis demonstrates that the counterbend emerges as a fundamental property of sliding resistance in cross-linked filamentous polymer bundles, which also suggests that cross-linking proteins may contribute to the regulation of the flagellar waveform in swimming sperm via counterbend mechanics. PMID:23824293
Distinctive features of transport in topological insulators
NASA Astrophysics Data System (ADS)
Sacksteder, Vincent; Wu, Quansheng; Arnardottir, Kristin; Shelykh, Ivan; Kettemann, Stefan
2015-03-01
The surface states of a topological insulator in a fine-tuned magnetic field are ideal candidates for realizing a topological metal which is protected against disorder. Its signatures are (1) a conductance plateau in long wires and (2) a conductivity which always increases with sample size. We numerically show that the bulk substantially accelerates the conductance plateaus's decay in a magnetic field. It also reduces the effects of surface disorder and causes the magnitude of the surface conductivity and the magnetoconductivity to depend systematically on sample details such as doping and disorder strength. In addition, we predict a new signature of the topological state: at low temperatures the magnetoresistance will deviate strongly from the Hikami-Larkin-Nagaoka (HLN) formula. In this regime the magnetoresistance is dominated by scattering processes which wrap around the TI sample. The HLN formula's shoulder is replaced by a feature with a larger critical field magnetic strength that is caused by wrapping. Inside the wrapping regime the magnetoconductance will lose its dependence on temperature. This new topological signature should be visible in the same samples and temperatures where the Altshuler-Aronov-Spivak (AAS) effect has already been observed.
Optimizing the sensing performance of a single-rod fluxgate magnetometer using thin magnetic wires
NASA Astrophysics Data System (ADS)
Can, Hava; Svec, Peter, Jr.; Tanrıseven, Sercan; Bydzovsky, Jan; Birlikseven, Cengiz; Sözeri, Hüseyin; Svec, Peter, Sr.; Topal, Uğur
2015-11-01
This paper presents the optimal conditions for the design of a single-rod fluxgate magnetometer using Co-based amorphous magnetic wires with reduced geometrical dimensions of 100 μm in diameter. In order to enhance the performance of the current sensor (i.e. the noise level, the sensitivity, the dynamical range, the scaling factor, etc), the core materials were subjected to annealing at different annealing temperatures in a longitudinal magnetic field ranging from 0 to 0.5 T. The B-H measurements have shown that the heat treatments significantly change the magnetic parameters of the cores (the saturation field, the initial and apparent permeabilities). For instance, the initial permeability μ i attains values of between 3500 and 4700 depending on the treatment conditions. These magnetic parameters were subsequently correlated with the sensor performance by using the principles of the fluxgate physics. Consequently, the enhanced fluxgate effect with improved sensing characteristics has been obtained by annealing the wire core at 250 °C (B = 0 T). It is shown that this magnetic wire with a sensing area of 0.00785 mm2 is suitable as a sensor core for the nondestructive testing of metallic objects and the surfaces of magnetic cards. The sensor signal shows perfect linear dependence to dc or low frequency fields up to ~1 Oe. The fitting parameters R 2 of 0.9998 could be achieved in a dc field interval of -1.0 Oe and 1.0 Oe (when R 2 =1.0, all points lie exactly on the curve with no scatter). Such linearity has not been seen in such a large dynamical range until now in the rod-type single-core fluxgates. It is also shown that there is no hysteresis on the V 2f -H dc graphs (the V 2f is the sensor signal) even after applying fields as high as 100 Oe. Besides, the cross-field effect is almost zero due to the geometry of the long-thin wire.
Large-eddy simulation, fuel rod vibration and grid-to-rod fretting in pressurized water reactors
Christon, Mark A.; Lu, Roger; Bakosi, Jozsef; ...
2016-10-01
Grid-to-rod fretting (GTRF) in pressurized water reactors is a flow-induced vibration phenomenon that results in wear and fretting of the cladding material on fuel rods. GTRF is responsible for over 70% of the fuel failures in pressurized water reactors in the United States. Predicting the GTRF wear and concomitant interval between failures is important because of the large costs associated with reactor shutdown and replacement of fuel rod assemblies. The GTRF-induced wear process involves turbulent flow, mechanical vibration, tribology, and time-varying irradiated material properties in complex fuel assembly geometries. This paper presents a new approach for predicting GTRF induced fuelmore » rod wear that uses high-resolution implicit large-eddy simulation to drive nonlinear transient dynamics computations. The GTRF fluid–structure problem is separated into the simulation of the turbulent flow field in the complex-geometry fuel-rod bundles using implicit large-eddy simulation, the calculation of statistics of the resulting fluctuating structural forces, and the nonlinear transient dynamics analysis of the fuel rod. Ultimately, the methods developed here, can be used, in conjunction with operational management, to improve reactor core designs in which fuel rod failures are minimized or potentially eliminated. Furthermore, robustness of the behavior of both the structural forces computed from the turbulent flow simulations and the results from the transient dynamics analyses highlight the progress made towards achieving a predictive simulation capability for the GTRF problem.« less
Large-eddy simulation, fuel rod vibration and grid-to-rod fretting in pressurized water reactors
DOE Office of Scientific and Technical Information (OSTI.GOV)
Christon, Mark A.; Lu, Roger; Bakosi, Jozsef
Grid-to-rod fretting (GTRF) in pressurized water reactors is a flow-induced vibration phenomenon that results in wear and fretting of the cladding material on fuel rods. GTRF is responsible for over 70% of the fuel failures in pressurized water reactors in the United States. Predicting the GTRF wear and concomitant interval between failures is important because of the large costs associated with reactor shutdown and replacement of fuel rod assemblies. The GTRF-induced wear process involves turbulent flow, mechanical vibration, tribology, and time-varying irradiated material properties in complex fuel assembly geometries. This paper presents a new approach for predicting GTRF induced fuelmore » rod wear that uses high-resolution implicit large-eddy simulation to drive nonlinear transient dynamics computations. The GTRF fluid–structure problem is separated into the simulation of the turbulent flow field in the complex-geometry fuel-rod bundles using implicit large-eddy simulation, the calculation of statistics of the resulting fluctuating structural forces, and the nonlinear transient dynamics analysis of the fuel rod. Ultimately, the methods developed here, can be used, in conjunction with operational management, to improve reactor core designs in which fuel rod failures are minimized or potentially eliminated. Furthermore, robustness of the behavior of both the structural forces computed from the turbulent flow simulations and the results from the transient dynamics analyses highlight the progress made towards achieving a predictive simulation capability for the GTRF problem.« less
77 FR 21397 - Airworthiness Directives; Airbus Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2012-04-10
... electrical circuit in the Right Hand (RH) wing must be modified in order to ensure better segregation between... RH wing pylon area to the generator wire bundle of engine 2. The modification of this zone was... authority of the FAA Administrator. ``Subtitle VII: Aviation Programs,'' describes in more detail the scope...
Fabrication of bundle-structured tube-leaky optical fibers for infrared thermal imaging
NASA Astrophysics Data System (ADS)
Kobayashi, T.; Katagiri, T.; Matsuura, Y.
2017-02-01
Bundled glass tubular fibers were fabricated by glass drawing technique for endoscopic infrared-thermal imaging. The bundle fibers were made of borosilicate glass and have a structure like a photonic crystal fiber having multiple hollow cores. Fabricated fibers have a length of 90 cm and each pixel sizes are less than 80 μm. By setting the thickness of glass wall to a quarter-wavelength optical thickness, light is confined in the air core as a leaky mode with a low loss owing to the interference effect of the thin glass wall and this type of hollow-core fibers is known as tube leaky fibers. The transmission losses of bundled fibers were firstly measured and it was found that bundled tube-leaky fibers have reasonably low transmission losses in spite of the small pixel size. Then thermal images were delivered by the bundled fibers combining with an InSb infrared camera. Considering applications with rigid endoscopes, an imaging system composed of a 30-cm long fiber bundle and a half-ball lens with a diameter of 2 mm was fabricated. By using this imaging system, a metal wire with a thickness of 200 μm was successfully observed and another test showed that the minimum detected temperature was 32.0 °C and the temperature resolution of the system was around 0.7 °C.
Apparatus producing constant cable tension for intermittent demand
Lauritzen, T.
1984-05-23
This invention relates to apparatus for producing constant tension in cable or the like when it is unreeled and reeled from a drum or spool under conditions of intermittent demand. The invention is particularly applicable to the handling of superconductive cable, but the invention is also applicable to the unreeling and reeling of other strands, such as electrical cable, wire, cord, other cables, fish line, wrapping paper and numerous other materials.
NASA Astrophysics Data System (ADS)
Ruan, Shipeng; Dong, Qing; Zhang, Lei; Wang, Lijun
2017-09-01
The effect of controlled rolling and cooling on microstructure and mechanical properties of alloy structure steel 30CrMnTi wire rod with diameter 6.5mm was studied. The results show that the lower finish rolling temperature resulted in a decrease in tensile strength but an increase in elongation and reduction of area. When the finish rolling temperature decreases from 950°C to 850°C, the tensile strength value decreases from 750MPa to 660MPa, and the elongation increases from 21% to 30%, the reduction of area increases from 64% to 71%. The grain size also refines from 20μm to 9.9μm when the finish rolling temperature decreases from 950°C to 850°C. The decrease of tensile strength is due to the change of microstructure which evolved from more bainite to ferrite and pearlite.
Barzi, E.; Bossert, M.; Gallo, G.; ...
2011-12-21
A major thrust in Fermilab's accelerator magnet R&D program is the development of Nb 3Sn wires which meet target requirements for high field magnets, such as high critical current density, low effective filament size, and the capability to withstand the cabling process. The performance of a number of strands with 150/169 restack design produced by Oxford Superconducting Technology was studied for round and deformed wires. To optimize the maximum plastic strain, finite element modeling was also used as an aid in the design. Results of mechanical, transport and metallographic analyses are presented for round and deformed wires.
NASA Technical Reports Server (NTRS)
Stueber, Thomas J.
1991-01-01
Recent studies involving the use of polyimide Kapton coated wires indicate that if a momentary electrical short circuit occurs between two wires, sufficient heating of the Kapton can occur to thermally char (pyrolyze) the Kapton. Such charred Kapton has sufficient electrical conductivity to create an arc which tracks down the wires and possibly propagates to adjoining wires. These studies prompted an investigation to ascertain the likelihood of the Kapton pyrolysis, arc tracking and propagation phenomena, and the magnitude of destruction conceivably inflicted on Space Station Freedom's (SSF) Flexible Current Carrier (FCC) for the photovoltaic array. The geometric layout of the FCC, having a planar-type orientation as opposed to bundles, may reduce the probability of sustaining an arc. An experimental investigation was conducted to simulate conditions under which an arc can occur on the FCC of SSF, and the consequences of arc initiation.
NASA Technical Reports Server (NTRS)
Stueber, Thomas J.
1991-01-01
Recent studies involving the use of polyimide Kapton coated wires indicate that if a momentary electrical short circuit occurs between two wires, sufficient heating of the Kapton can occur to themally chlar (pyrolyze) the Kapton. Such charred Kapton has sufficient electricxl conductivity to create an arc which tracks down the wires and possibly propagates to adjoining wires. These studies prompted an invetigation to ascertain the likelihood of Kapton pyrolysis, arc tracking and propagation phenomena, and the magnitude of destruction conceivably inflicted on Space Station Freedom's (SSF's) Flexible Current Carrier (FCC) for the photovoltaic array. The geometric layout of the FCC, having a planar-type orientation as opposed to bundles, may reduce the probability of sustaining an arc. An experimental investigation was conducted to simulate conditions under which an arc can occur on the FCC of the SSF, and the consequences of arc initiation.
NASA Technical Reports Server (NTRS)
Noebe, Ronald; Draper, Susan; Gaydosh, Darrell; Garga, Anita; Lerch, Brad; Penney, Nicholas; Begelow, Glen; Padula, Santo, II; Brown, Jeff
2006-01-01
TiNiPt shape memory alloys are particularly promising for use as solid state actuators in environments up to 300 C, due to a reasonable balance of properties, including acceptable work output. However, one of the challenges to commercializing a viable high-temperature shape memory alloy (HTSMA) is to establish the appropriate primary and secondary processing techniques for fabrication of the material in a required product form such as rod and wire. Consequently, a Ti(50.5)Ni(29.5)Pt20 alloy was processed using several techniques including single-pass high-temperature extrusion, multiple-pass high-temperature extrusion, and cold drawing to produce bar stock, thin rod, and fine wire, respectively. The effects of heat treatment on the hardness, grain size, room temperature tensile properties, and transformation temperatures of hot- and cold-worked material were examined. Basic tensile properties as a function of temperature and the strain-temperature response of the alloy under constant load, for the determination of work output, were also investigated for various forms of the Ti(50.5)Ni(29.5)Pt20 alloy, including fine wire.
NASA Astrophysics Data System (ADS)
Zhang, An-Qi; Li, Hui-Jun; Qian, Dong-Jin; Chen, Meng
2014-04-01
We report a kinetically-controlled template-free room-temperature production of hollow silica materials with various novel morphologies, including tubes, crutches, ribbons, bundles and bells. The obtained products, which grew in a well-controlled manner, were monodispersed in shape and size. The role of ammonia, sodium citrate, polyvinylpyrrolidone, chloroauric acid and NaCl in shape control is discussed in detail. The oriented growth of these micro-/nanostructures directed by reverse micelles followed a solution-solution-solid (SSS) mechanism, similar to the classic vapor-liquid-solid mechanism. The evolution processes of silica rods, tubes, crutches, bundles and bells were recorded using transmission electron microscopy to prove the SSS mechanism.
Carbon nanotube wires with continuous current rating exceeding 20 Amperes
NASA Astrophysics Data System (ADS)
Cress, Cory D.; Ganter, Matthew J.; Schauerman, Christopher M.; Soule, Karen; Rossi, Jamie E.; Lawlor, Colleen C.; Puchades, Ivan; Ubnoske, Stephen M.; Bucossi, Andrew R.; Landi, Brian J.
2017-07-01
A process to fabricate carbon nanotube (CNT) wires with diameters greater than 1 cm and continuous current carrying capability exceeding 20 A is demonstrated. Wires larger than 5 mm are formed using a multi-step radial densification process that begins with a densified CNT wire core followed by successive wrapping of additional CNT material to increase the wire size. This process allows for a wide range of wire diameters to be fabricated, with and without potassium tetrabromoaurate (KAuBr4) chemical doping, and the resulting electrical and thermal properties to be characterized. Electrical measurements are performed with on/off current steps to obtain the maximum current before reaching a peak CNT wire temperature of 100 °C and before failure, yielding values of instantaneous currents in excess of 45 A for KAuBr4 doped CNT wires with a diameter of 6 mm achieved prior to failure. The peak temperature of the wires at failure (˜530 °C) is correlated with the primary decomposition peak observed in thermal gravimetric analysis of a wire sample confirming that oxidation is the primary failure mode of CNT wires operated in air. The in operando stability of doped CNT wires is confirmed by monitoring the resistance and temperature, which remain largely unaltered over 40 days and 1 day for wires with 1.5 mm and 11.2 mm diameters, respectively. The 100 °C continuous current rating, or ampacity, is measured for a range of doped CNT wire diameters and corresponding linear mass densities ρL. To describe the results, a new form of the fuse-law, where the critical current is defined as I ∝ρL3 /4, is developed and shows good agreement with the experimental data. Ultimately, CNT wires are shown to be stable electrical conductors, with failure current densities in excess of 50 A in the case of a convectively cooled 11.2 mm doped CNT wire, and amenable for use in applications that have long-term, high-current demands.
NASA Astrophysics Data System (ADS)
Briggs, M.; Lautz, L. K.; McKenzie, J. M.
2010-12-01
Small dams enhance hyporheic interaction by creating punctuated head differentials along streams, thereby affecting redox conditions and nutrient cycling in the streambed. As beaver populations return, they create dams that alter hyporheic flowpaths locally, an effect which may integrate at the reach scale to produce a net hydrological and ecological functional change. Streambed heterogeneity around beaver dams combines with varied morphology, head differentials and stream velocities to create patterns of hyporheic seepage flux that vary in both space and time. Heat has been used as a groundwater tracer for many years, but it’s dependence on spatially disperse point measurements has only recently been resolved by the development of Distributed Temperature Sensing (DTS) fiber-optic technology. Modified applications of DTS include wrapping the fiber around a mandrel to increase spatial resolution dramatically. Wrapped configurations can be installed vertically in the streambed to provide data for heat transport modeling of vertical hyporheic flux. The vertically continuous dataset generated with DTS may be more informative regarding subsurface heterogeneity than more commonly used spatially discrete thermocouples. We installed a total of nine wrapped DTS rods with 1.4 cm vertical spatial resolution above two beaver dams in Cherry Creek, a tributary of the Little Popo Agie River in Lander, Wyoming, USA. Data was collected over 20 min periods in dual-ended mode continuously for one month (10-Jul to 10-Aug 2010) during baseflow recession, as discharge dropped from 384 Ls-1 to 211 Ls-1. The temperature rods were installed to at least 0.75 m depth within bed sediments at varied distances upstream of the dams in diverse stream morphological units, which ranged from gravel bars to clay lined pools. Diurnal fluctuations in stream temperature were generally between 4.5 and 5.5 oC in amplitude, imparting a strong potential signal for propagation into the bed due to advective hyporheic flux. In many locations monthly temperature standard deviations at the 10 cm depth were larger than that of the overlying stream water, indicating direct heating of the streambed by solar radiation was an important process, even in that high velocity system. The high-resolution temperature records revealed local heterogeneity in the streambed at each rod and indicated the largest hyporheic flux was within gravel bars close to the dams. The smallest flux was through a gravel bar farther upstream of the dam, and through the deepest portions of pools closer to the dam. High flux regions had monthly temperature standard deviations close to that of the stream (1.5 oC) at shallow depths, while shallow sediments in pools had much more muted temperature oscillations. At 0.5 m depth, all rods had similar, smaller temperature standard deviations, ranging from 0.64-0.80 oC. The extensive and spatially continuous data set generated using DTS allowed us to determine hyporheic flux patterns for virtually any depth and time along the high-resolution temperature rods, a crucial step for understanding transient patterns in biogeochemical processing around beaver dams.
A new infusion pathway intactness monitoring system.
Ogawa, Hidekuni; Yonezawa, Yoshiharu; Maki, Hiromichi; Ninomiya, Ishio; Sata, Koji; Hamada, Shingo; Caldwell, W Morton
2006-01-01
A new infusion pathway monitoring system has been developed for hospital and home use. The system consists of linear integrated circuits and a low-power 8-bit single chip microcomputer which constantly monitors the infusion pathway intactness. An AC (alternating current) voltage is induced on the patient's body by electrostatic coupling from the normal 100 volt, 60 Hz AC power line wiring field in the patient's room. The induced AC voltage can be recorded by a main electrode wrapped around the infusion polyvinyl chloride tube. A reference electrode is wrapped on the electrode to monitor the AC voltage around the main electrode. If the injection needle or infusion tube becomes detached, then the system detects changes in the induced AC voltages and alerts the nursing station, via the nurse call system or PHS (personal handy phone system).
NASA Technical Reports Server (NTRS)
Hang, Richard
2015-01-01
The presentation will overview NASA Armstrong Flight Research Centers flight test capabilities, which can provide various means for flight testing of passive and active wireless sensor systems, also, it will address the needs of the wireless data acquisition solutions for the centers flight instrumentation issues such as additional weight caused by added instrumentation wire bundles, connectors, wire cables routing, moving components, etc., that the Passive Wireless Sensor Technology Workshop may help. The presentation shows the constraints and requirements that the wireless sensor systems will face in the flight test applications.
[Columbia Sensor Diagrams]. Revised
NASA Technical Reports Server (NTRS)
2003-01-01
A two dimensional graphical event sequence of the time history of relevant sensor information located in the left wing and wheel well areas of the Space Shuttle Columbia Orbiter is presented. Information contained in this graphical event sequence include: 1) Sensor location on orbiter and its associated wire bindle in X-Y plane; 2) Wire bundle routing; 3) Description of each anomalous sensor event; 4) Time annotation by (a) GMT, (b) time relative to LOS, (c) time history bar, and (d) ground track; and 5) Graphical display of temperature rise (based on delta temperature from point it is determined to be anomalous).
Experience using individually supplied heater rods in critical power testing of advanced BWR fuel
DOE Office of Scientific and Technical Information (OSTI.GOV)
Majed, M.; Morback, G.; Wiman, P.
1995-09-01
The ABB Atom FRIGG loop located in Vasteras Sweden has during the last six years given a large experience of critical power measurements for BWR fuel designs using indirectly heated rods with individual power supply. The loop was built in the sixties and designed for maximum 100 bar pressure. Testing up to the mid eighties was performed with directly heated rods using a 9 MW, 80 kA power supply. Providing test data to develop critical power correlations for BWR fuel assemblies requires testing with many radial power distributions over the full range of hydraulic conditions. Indirectly heated rods give largemore » advantages for the testing procedure, particularly convenient for variation of individual rod power. A test method being used at Stern Laboratories (formerly Westinghouse Canada) since the early sixties, allows one fuel assembly to simulate all required radial power distributions. This technique requires reliable indirectly heated rods with independently controlled power supplies and uses insulated electric fuel rod simulators with built-in instrumentation. The FRIGG loop was adapted to this system in 1987. A 4MW power supply with 10 individual units was then installed, and has since been used for testing 24 and 25 rod bundles simulating one subbundle of SVEA-96/100 type fuel assemblies. The experience with the system is very good, as being presented, and it is selected also for a planned upgrading of the facility to 15 MW.« less
On the look-up tables for the critical heat flux in tubes (history and problems)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kirillov, P.L.; Smogalev, I.P.
1995-09-01
The complication of critical heat flux (CHF) problem for boiling in channels is caused by the large number of variable factors and the variety of two-phase flows. The existence of several hundreds of correlations for the prediction of CHF demonstrates the unsatisfactory state of this problem. The phenomenological CHF models can provide only the qualitative predictions of CHF primarily in annular-dispersed flow. The CHF look-up tables covered the results of numerous experiments received more recognition in the last 15 years. These tables are based on the statistical averaging of CHF values for each range of pressure, mass flux and quality.more » The CHF values for regions, where no experimental data is available, are obtained by extrapolation. The correction of these tables to account for the diameter effect is a complicated problem. There are ranges of conditions where the simple correlations cannot produce the reliable results. Therefore, diameter effect on CHF needs additional study. The modification of look-up table data for CHF in tubes to predict CHF in rod bundles must include a method which to take into account the nonuniformity of quality in a rod bundle cross section.« less
VICTORIA-92 pretest analyses of PHEBUS-FPT0
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bixler, N.E.; Erickson, C.M.
FPT0 is the first of six tests that are scheduled to be conducted in an experimental reactor in Cadarache, France. The test apparatus consists of an in-pile fuel bundle, an upper plenum, a hot leg, a steam generator, a cold leg, and a small containment. Thus, the test is integral in the sense that it attempts to simulate all of the processes that would be operative in a severe nuclear accident. In FPT0, the fuel will be trace irradiated; in subsequent tests high burn-up fuel will be used. This report discusses separate pretest analyses of the FPT0 fuel bundle andmore » primary circuit have been conducted using the USNRC`s source term code, VICTORIA-92. Predictions for release of fission product, control rod, and structural elements from the test section are compared with those given by CORSOR-M. In general, the releases predicted by VICTORIA-92 occur earlier than those predicted by CORSOR-M. The other notable difference is that U release is predicted to be on a par with that of the control rod elements; CORSOR-M predicts U release to be about 2 orders of magnitude greater.« less
Effects of Purification on the Crystallization of Lysozyme
NASA Technical Reports Server (NTRS)
Ewing, Felecia L.; Forsythe, Elizabeth L.; Van Der Woerd, Mark; Pusey, Marc L.
1996-01-01
We have additionally purified a commercial lysozyme preparation by cation exchange chromatography, followed by recrystallization. This material is 99.96% pure with respect to macromolecular impurities. At basic pH, the purified lysozyme gave only tetragonal crystals at 20 C. Protein used directly from the bottle, prepared by dialysis against distilled water, or which did not bind to the cation exchange column had considerably altered crystallization behavior. Lysozyme which did not bind to the cation exchange column was subsequently purified by size exclusion chromatography. This material gave predominately bundles of rod-shaped crystals with some small tetragonal crystals at lower pHs. The origin of the bundled rod habit was postulated to be a thermally dependent tetragonal- orthorhombic change in the protein structure. This was subsequently ruled out on the basis of crystallization behavior and growth rate experiments. This suggests that heterogeneous forms of lysozyme may be responsible. These results demonstrate three classes of impurities: (1) small molecules, which may be removed by dialysis; (2) macromolecules, which are removable by chromatographic techniques; and (3) heterogeneous forms of the protein, which can be removed in this case by cation exchange chromatography. Of these, heterogeneous forms of the lysozyme apparently have the greatest affect on its crystallization behavior.
NASA Astrophysics Data System (ADS)
Andrawis, Alfred S.
1994-10-01
The problem addressed by this report is the large size and heavy weight of the cable bundle, used for controlling a Multidegree-Of-Freedom Serpentine Truss Manipulator arm, which imposes limitations on the manipulator arm maneuverability. This report covers a design of an optical fiber network to replace the existing copper wire network of the Serpentine Truss Manipulator. This report proposes a fiber network design which significantly reduces the bundle size into two phases. The first phase does not require any modifications for the manipulator architecture, while the other requires major modifications. Design philosophy, hardware details and schematic diagrams are presented.
NASA Technical Reports Server (NTRS)
Andrawis, Alfred S.
1994-01-01
The problem addressed by this report is the large size and heavy weight of the cable bundle, used for controlling a Multidegree-Of-Freedom Serpentine Truss Manipulator arm, which imposes limitations on the manipulator arm maneuverability. This report covers a design of an optical fiber network to replace the existing copper wire network of the Serpentine Truss Manipulator. This report proposes a fiber network design which significantly reduces the bundle size into two phases. The first phase does not require any modifications for the manipulator architecture, while the other requires major modifications. Design philosophy, hardware details and schematic diagrams are presented.
Manual tube-to-tubesheet welding torch
Kiefer, Joseph H.; Smith, Danny J.
1982-01-01
A welding torch made of a high temperature plastic which fits over a tube intermediate the ends thereof for welding the juncture between the tube and the back side of a tube plate and has a ballooned end in which an electrode, filler wire guide, fiber optic bundle, and blanketing gas duct are disposed.
Method and tool for contracting tubular members by electro-hydraulic forming before hydroforming
Golovashchenko, Sergey Fedorovich [Beverly Hills, MI
2011-03-15
A tubular preform is contracted in an electro-hydraulic forming operation. The tubular preform is wrapped with one or more coils of wire and placed in a chamber of an electro-hydraulic forming tool. The electro-hydraulic forming tool is discharged to form a compressed area on a portion of the tube. The tube is then placed in a hydroforming tool that expands the tubular preform to form a part.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Han, D; Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, Toronto, Ontario; Safigholi, H
2015-06-15
Purpose: To evaluate the impact of using gold wires to differentially fill various channels on plan quality compared with conventional T&R applicator, inside a novel directional modulated brachytherapy (DMBT) tandem applicator for cervical cancer brachytherapy. Materials and Methods: The novel DMBT tandem applicator has a 5.4-mm diameter MR-compatible tungsten alloy enclosed in a 0.3-mm thick plastic tubing that wraps around the tandem. To modulate the radiation intensity, 6 symmetric peripheral holes of 1.3-mm diameter are grooved along the tungsten alloy rod. These grooved holes are differentially filled with gold wires to generate various degrees of directional beams. For example, threemore » different fill patterns of 1) all void, 2) all filled except the hole containing the 192-Ir source, and 3) two adjacent holes to the 192-Ir source filled were Monte Carlo simulated. The resulting 3D dose distributions were imported into an in-house-coded inverse optimization planning system to generate HDR brachytherapy clinical plans for 19 patient cases. All plans generated were normalized to the same D90 as the clinical plans and D2cc doses of OARs were evaluated. Prescription ranged between 15 and 17.5Gy. Results: In general, the plans in case 1) resulted in the highest D2cc doses for the OARs with 11.65±2.30Gy, 7.47±3.05Gy, and 9.84±2.48Gy for bladder, rectum, and sigmoid, respectively, although the differences were small. For the case 2), D2cc doses were 11.61±2.29Gy, 7.41±3.07Gy, and 9.75±2.45Gy, respectively. And, for the case 3), D2cc doses were 11.60±2.28Gy, 7.41±3.05Gy, and 9.74±2.45Gy, respectively. Difference between 1) and 2) cases were small with the average D2cc difference of <0.64%. Difference between 1) and 3) cases were even smaller with the average D2cc difference of <0.1%. Conclusions: There is a minimal clinical benefit by differentially filling grooved holes in the novel DMBT tandem applicator for image guided cervical cancer brachytherapy.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chafetz, Henry S.
1990-04-30
Bacteria induce the precipitation of calcium carbonate in the laboratory and in nature by altering their chemical environment. Geologists are recognizing the possibility that bacterially induced precipitates may form significant mineral deposits, unfortunately, there are currently no sound criteria by which they can be recognized in recent sediments, or in the rock record. Cultures of aerobic and facultative bacteria from cyanobacterial mats on Andros Island, Bahamas, and Baffin Bay, Texas, induced the precipitation of calcium carbonate under controlled conditions. Crusts, the largest features formed, are composed of 5--200μm diameter bundles which are, in turn, composed of numerous individual crystals. Themore » smallest observed features are 0.1--0.4μm spheres and rods which comprise some individual crystals and crystal bundles. Crystal bundles resembling rhombohedra, tetragonal disphenoids, tetragonal dipyramids, and calcite dumbbells appear to be uniquely bacterial in origin, and they have all been observed in recent sediments. Swollen rods, discs, curved dumbbells, and 50--200μm optically continuous crystals resembling brushes may be uniquely bacterial in origin, however, they have not been reported by other laboratories nor observed in natural settings. Presence of any of these forms in recent sediments should be taken as strong evidence for bacterial influence. Spheres and aragonite dumbbells have also been observed in natural environments, however, they are not always bacterial in origin. Precipitation of calcium carbonate occurs preferentially on dead cyanobacteria in the presence of bacteria. Lithification of algal mats to form stromatolites may take place in the zone of decaying organic matter due to bacterial activity.« less
Bacterially induced precipitation of CaCO sub 3 : An example from studies of cyanobacterial mats
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chafetz, H.S.
1990-04-30
Bacteria induce the precipitation of calcium carbonate in the laboratory and in nature by altering their chemical environment. Geologists are recognizing the possibility that bacterially induced precipitates may form significant mineral deposits, unfortunately, there are currently no sound criteria by which they can be recognized in recent sediments, or in the rock record. Cultures of aerobic and facultative bacteria from cyanobacterial mats on Andros Island, Bahamas, and Baffin Bay, Texas, induced the precipitation of calcium carbonate under controlled conditions. Crusts, the largest features formed, are composed of 5--200{mu}m diameter bundles which are, in turn, composed of numerous individual crystals. Themore » smallest observed features are 0.1--0.4{mu}m spheres and rods which comprise some individual crystals and crystal bundles. Crystal bundles resembling rhombohedra, tetragonal disphenoids, tetragonal dipyramids, and calcite dumbbells appear to be uniquely bacterial in origin, and they have all been observed in recent sediments. Swollen rods, discs, curved dumbbells, and 50--200{mu}m optically continuous crystals resembling brushes may be uniquely bacterial in origin, however, they have not been reported by other laboratories nor observed in natural settings. Presence of any of these forms in recent sediments should be taken as strong evidence for bacterial influence. Spheres and aragonite dumbbells have also been observed in natural environments, however, they are not always bacterial in origin. Precipitation of calcium carbonate occurs preferentially on dead cyanobacteria in the presence of bacteria. Lithification of algal mats to form stromatolites may take place in the zone of decaying organic matter due to bacterial activity.« less
Ren, Bo; Zhai, Zhenbo; Guo, Kai; Liu, Yanpu; Hou, Weihuan; Zhu, Qingsheng; Zhu, Jinyu
2015-01-01
The aim of this study is to investigate the effect of porous tantalum material in repair tibial defects caused by firearm injuries in a rabbit model. A multifunctional biological impact machine was used to establish a rabbit tibial defect model of firearm injury. Porous tantalum rods were processed into a hollow cylinder. Kirschner wires were used for intramedullary fixation. We compared the differences of the bone ingrowth of the porous tantalum material by gross observations, X-rays and histological evaluations. The radiographic observations revealed that fibrous tissue covered the material surface after 4 weeks, and periosteal reactions and new bone callus extending materials appeared after 8 weeks. After 16 weeks, the calluses of the firearm injury group were completely wrapped around a porous tantalum material. The group with the highest Lane-Sandhu X-rays cores was the firearm injury and tantalum implant group, and the blank control group exhibited the lowest scores. The histological evaluations revealed that the presence of new bone around the biomaterial had grown into the porous tantalum. By the 16th week, the areas of bone tissue of the firearm injury group was significant higher than that of non-firearm injury group (P<0.05). The comminuted fractures treated with tantalum cylinders exhibited greater bone ingrowth in the firearm injury group. In conditions of firearm injuries, the porous tantalum biomaterial exhibited bone ingrowth that was beneficial to the treatment of bone defects. PMID:26131078
NASA Technical Reports Server (NTRS)
Few, Alex
2016-01-01
NEAScout, a 6U cubesat and secondary payload on NASA's EM-1, will use an 85 sq m solar sail to travel to a near-earth asteroid at about 1 Astronomical Unit (about 1.5 x 10(exp 8) km) for observation and reconnaissance1. A combination of reaction wheels, reaction control system, and a slow rotisserie roll about the solar sail's normal axis were expected to handle attitude control and adjust for imperfections in the deployed sail during the 2.5-year mission. As the design for NEAScout matured, one of the critical design parameters, the offset in the center of mass and center of pressure (CP/CM offset), proved to be sub-optimal. After significant mission and control analysis, the CP/CM offset was accommodated by the addition of a new subsystem to NEAScout. This system, called the Active Mass Translator (AMT), would reside near the geometric center of NEAScout and adjust the CM by moving one portion of the flight system relative to the other. The AMT was given limited design space - 17 mm of the vehicle's assembly height-and was required to generate +/-8 cm by +/-2 cm translation to sub-millimeter accuracy. Furthermore, the design must accommodate a large wire bundle of small gage, single strand wire and coax cables fed through the center of the mechanism. The bend radius, bend resistance, and the exposure to deep space environment complicates the AMT design and operation and necessitated a unique design to mitigate risks of wire bundle damage, binding, and cold-welding during operation. This paper will outline the design constraints for the AMT, discuss the methods and reasoning for design, and identify the lessons learned through the designing, breadboarding and testing for the low-profile translation stages with wire feedthrough capability.
NASA Technical Reports Server (NTRS)
Few, Alex
2016-01-01
NEAScout, a 6U cubesat and secondary payload on NASA's EM-1, will use an 85 sq m solar sail to travel to a near-earth asteroid at about 1 Astronomical Unit (about 1.5 x 10(exp 8) km) for observation and reconnaissance1. A combination of reaction wheels, reaction control system, and a slow rotisserie roll about the solar sail's normal axis were expected to handle attitude control and adjust for imperfections in the deployed sail during the 2.5-year mission. As the design for NEAScout matured, one of the critical design parameters, the offset in the center of mass and center of pressure (CP/CM offset), proved to be sub-optimal. After significant mission and control analysis, the CP/CM offset was accommodated by the addition of a new subsystem to NEAScout. This system, called the Active Mass Translator (AMT), would reside near the geometric center of NEAScout and adjust the CM by moving one portion of the flight system relative to the other. The AMT was given limited design space - 17 mm of the vehicle's assembly height-and was required to generate +/-8 cm by +/-2 cm translation to sub-millimeter accuracy. Furthermore, the design must accommodate a large wire bundle of small gage, single strand wire and coax cables fed through the center of the mechanism. The bend radius, bend resistance, and the exposure to deep space environment complicates the AMT design and operation and necessitated a unique design to mitigate risks of wire bundle damage, binding, and cold-welding during operation. This paper will outline the design constraints for the AMT, discuss the methods and reasoning for design, and identify the lessons learned through the designing, breadboarding and testing for the low-profile translation stages with wire feedthrough capability.
NASA Astrophysics Data System (ADS)
Sai Anuhya, Danam; Gupta, Ashutosh; Nayan, Niraj; Narayana Murty, S. V. S.; Manna, R.; Sastry, G. V. S.
2014-08-01
Al-Cu-Mg alloys are extensively used for riveting applications in aerospace industries due to their relatively high shear strength coupled with high plasticity. The significant advantage of using V65 aluminum alloy ((Al-4Cu-0.2Mg) for rivet application also stems from its significantly slower natural aging kinetics, which gives operational flexibility to carryout riveting operation even after 4 days of solution heat treatment, in contrast to its equivalent alloy AA2024.Rivets are usually made by cold heading of wire rods. In order to form a defect free rivet head, grain size control in wire rods is essential at each and every stage of processing right from casting onwards upto the final wire drawing stage. Wire drawing is carried out at room temperature to reduce diameter as well as impart good surface finish. In the present study, different microstructures in V65 alloy bars were produced by rolling at different temperatures (room temperature to 523K) and subsequently deformed by equal channel angular pressing (ECAP) at 423K upto an equivalent strain of 7. ECAP was carried out to study the effect of initial microstructure on grain refinement and degree of deformation on the evolution of ultrafine grain structure. The refinement of V65 alloy by ECAP is significantly influenced by Initial microstructure but amount of deformation strongly affects the evolution processes as revealed by optical microscopy and transmission electron microscopy.
Conceptual designs of conduction cooled MgB2 magnets for 1.5 and 3.0 T full body MRI systems
NASA Astrophysics Data System (ADS)
Baig, Tanvir; Amin, Abdullah Al; Deissler, Robert J.; Sabri, Laith; Poole, Charles; Brown, Robert W.; Tomsic, Michael; Doll, David; Rindfleisch, Matthew; Peng, Xuan; Mendris, Robert; Akkus, Ozan; Sumption, Michael; Martens, Michael
2017-04-01
Conceptual designs of 1.5 and 3.0 T full-body magnetic resonance imaging (MRI) magnets using conduction cooled MgB2 superconductor are presented. The sizes, locations, and number of turns in the eight coil bundles are determined using optimization methods that minimize the amount of superconducting wire and produce magnetic fields with an inhomogeneity of less than 10 ppm over a 45 cm diameter spherical volume. MgB2 superconducting wire is assessed in terms of the transport, thermal, and mechanical properties for these magnet designs. Careful calculations of the normal zone propagation velocity and minimum quench energies provide support for the necessity of active quench protection instead of passive protection for medium temperature superconductors such as MgB2. A new ‘active’ protection scheme for medium T c based MRI magnets is presented and simulations demonstrate that the magnet can be protected. Recent progress on persistent joints for multifilamentary MgB2 wire is presented. Finite difference calculations of the quench propagation and temperature rise during a quench conclude that active intervention is needed to reduce the temperature rise in the coil bundles and prevent damage to the superconductor. Comprehensive multiphysics and multiscale analytical and finite element analysis of the mechanical stress and strain in the MgB2 wire and epoxy for these designs are presented for the first time. From mechanical and thermal analysis of our designs we conclude there would be no damage to such a magnet during the manufacturing or operating stages, and that the magnet would survive various quench scenarios. This comprehensive set of magnet design considerations and analyses demonstrate the overall viability of 1.5 and 3.0 T MgB2 magnet designs.
Development of a High Performance, Low-Profile Translation Table with Wire Feedthrough
NASA Technical Reports Server (NTRS)
Few, Alex
2016-01-01
NEAScout, a 6U cubesat, will use an 85 sq m solar sail to travel to a near-earth asteroid for observation. Over the course of the 3-year mission, a combination of reaction wheels, cold gas reaction control system, and a slow rotisserie roll about the solar sail's normal axis were expected to handle attitude control and adjust for imperfections in the deployed sail. As the design for NEAScout matured, one of the critical design parameters, the offset in the center of mass and center of pressure (CP/CM offset), proved to be sub-optimal. After significant mission and control analysis, the CP/CM offset was addressed and a new subsystem was introduced to NEAScout. This system, called the Active Mass Translator (AMT), would reside near the geometric center of NEAScout and adjust the CM by moving one portion of the flight system relative to the other. The AMT was given limited design space-about 17 mm of the vehicle's assembly height-and was required to generate +/-10 cm by +/-5 cm translation to sub-millimeter accuracy. Furthermore, the design must accommodate a large wire bundle of small gage, single strand wire and coax cables fed through the center of the mechanism. The bend radius, bend resistance, and the exposure to deep space environment complicates the AMT design and operation and necessitated a unique design to mitigate risks of wire bundle damage, binding, and cold-welding during operation. This paper will outline the design constraints for the AMT, discuss the methods and reasoning for design, and identify the lessons learned through the design downselect process and breadboarding for designing low-profile translation stages with feedthrough capabilities.
Conceptual designs of conduction cooled MgB2 magnets for 1.5 and 3.0T full body MRI systems
Baig, Tanvir; Al Amin, Abdullah; Deissler, Robert J; Sabri, Laith; Poole, Charles; Brown, Robert W; Tomsic, Michael; Doll, David; Rindfleisch, Matthew; Peng, Xuan; Mendris, Robert; Akkus, Ozan; Sumption, Michael; Martens, Michael
2017-01-01
Conceptual designs of 1.5 and 3.0 T full-body magnetic resonance imaging (MRI) magnets using conduction cooled MgB2 superconductor are presented. The sizes, locations, and number of turns in the eight coil bundles are determined using optimization methods that minimize the amount of superconducting wire and produce magnetic fields with an inhomogeneity of less than 10 ppm over a 45 cm diameter spherical volume. MgB2 superconducting wire is assessed in terms of the transport, thermal, and mechanical properties for these magnet designs. Careful calculations of the normal zone propagation velocity and minimum quench energies provide support for the necessity of active quench protection instead of passive protection for medium temperature superconductors such as MgB2. A new ‘active’ protection scheme for medium Tc based MRI magnets is presented and simulations demonstrate that the magnet can be protected. Recent progress on persistent joints for multifilamentary MgB2 wire is presented. Finite difference calculations of the quench propagation and temperature rise during a quench conclude that active intervention is needed to reduce the temperature rise in the coil bundles and prevent damage to the superconductor. Comprehensive multiphysics and multiscale analytical and finite element analysis of the mechanical stress and strain in the MgB2 wire and epoxy for these designs are presented for the first time. From mechanical and thermal analysis of our designs we conclude there would be no damage to such a magnet during the manufacturing or operating stages, and that the magnet would survive various quench scenarios. This comprehensive set of magnet design considerations and analyses demonstrate the overall viability of 1.5 and 3.0 T MgB2 magnet designs. PMID:29170604
Conceptual designs of conduction cooled MgB2 magnets for 1.5 and 3.0T full body MRI systems.
Baig, Tanvir; Al Amin, Abdullah; Deissler, Robert J; Sabri, Laith; Poole, Charles; Brown, Robert W; Tomsic, Michael; Doll, David; Rindfleisch, Matthew; Peng, Xuan; Mendris, Robert; Akkus, Ozan; Sumption, Michael; Martens, Michael
2017-04-01
Conceptual designs of 1.5 and 3.0 T full-body magnetic resonance imaging (MRI) magnets using conduction cooled MgB 2 superconductor are presented. The sizes, locations, and number of turns in the eight coil bundles are determined using optimization methods that minimize the amount of superconducting wire and produce magnetic fields with an inhomogeneity of less than 10 ppm over a 45 cm diameter spherical volume. MgB 2 superconducting wire is assessed in terms of the transport, thermal, and mechanical properties for these magnet designs. Careful calculations of the normal zone propagation velocity and minimum quench energies provide support for the necessity of active quench protection instead of passive protection for medium temperature superconductors such as MgB 2 . A new 'active' protection scheme for medium T c based MRI magnets is presented and simulations demonstrate that the magnet can be protected. Recent progress on persistent joints for multifilamentary MgB 2 wire is presented. Finite difference calculations of the quench propagation and temperature rise during a quench conclude that active intervention is needed to reduce the temperature rise in the coil bundles and prevent damage to the superconductor. Comprehensive multiphysics and multiscale analytical and finite element analysis of the mechanical stress and strain in the MgB 2 wire and epoxy for these designs are presented for the first time. From mechanical and thermal analysis of our designs we conclude there would be no damage to such a magnet during the manufacturing or operating stages, and that the magnet would survive various quench scenarios. This comprehensive set of magnet design considerations and analyses demonstrate the overall viability of 1.5 and 3.0 T MgB 2 magnet designs.
A study on MFL based wire rope damage detection
NASA Astrophysics Data System (ADS)
Park, J.; Kim, J.-W.; Kim, J.; Park, S.
2017-04-01
Non-destructive testing on wire rope is in great demand to prevent safety accidents at sites where many heavy equipment using ropes are installed. In this paper, a research on quantification of magnetic flux leakage (MFL) signals were carried out to detect damages on wire rope. First, a simulation study was performed with a steel rod model using a finite element analysis (FEA) program. The leakage signals from the simulation study were obtained and it was compared for parameter: depth of defect. Then, an experiment on same conditions was conducted to verify the results of the simulation. Throughout the results, the MFL signal was quantified and a wire rope damage detection was then confirmed to be feasible. In further study, it is expected that the damage characterization of an entire specimen will be visualized as well.
Microfiber Structures for Sensor Applications
NASA Astrophysics Data System (ADS)
Harun, S. W.; Lim, K. S.; Ahmad, H.
Microfiber loop resonator (MLR) and microfiber knot resonator (MKR) are fabricated using melt-stretching method for applications in temperature and current sensor, respectively. The MLR is embedded into low refractive index polymer for robustness. Although the spacing of the transmission comb spectrum of the MLR is unchanged with temperature, the extinction ratio of the spectrum is observed to decrease linearly with temperature due to induced changes in the material's refractive index. The slope of the extinction ratio reduction against temperature is about 0.043dB/°C. With the assistance of a copper wire that is wrapped by the MKR, resonant wavelength can be tuned by varying the electric current delivered to the wire. The resonant wavelength change is based on the thermally induced optical phase shift in the MKR due to the heat produced by the flow of electric current over a short transit length. It is shown that the wavelength shift is linearly proportional to the square of current in the copper wire with a tuning slope of 46 pm/A2.
Byers, John A
2004-05-30
Heating of chromatographic columns, transfer lines, and other devices is often required in neuroscience research. For example, volatile compounds passing through a capillary column of a gas chromatograph (GC) can be split, with half exiting the instrument through a heated transfer line to an insect antenna or olfactory sensillum for electroantennographic detector (GC-EAD) recordings. The heated transfer line is used to prevent condensation of various chemicals in the capillary that would otherwise occur at room temperature. Construction of such a transfer line heater is described using (80/20%) nickel-chromium heating wire wrapped in a helical coil and powered by a 120/220 V ac rheostat. Algorithms were developed in a computer program to estimate the voltage at which a rheostat should be set to obtain the desired heater temperature for a specific coil. The coil attributes (radius, width, number of loops, or length of each loop) are input by the user, as well as AWG size of heating wire and desired heater temperature. The program calculates total length of wire in the helix, resistance of the wire, amperage used, and the voltage to set the rheostat. A discussion of semiochemical isolation methods using the GC-EAD and bioassays is presented.
New model for burnout prediction in channels of various cross-section
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bobkov, V.P.; Kozina, N.V.; Vinogrado, V.N.
1995-09-01
The model developed to predict a critical heat flux (CHF) in various channels is presented together with the results of data analysis. A model is the realization of relative method of CHF describing based on the data for round tube and on the system of correction factors. The results of data description presented here are for rectangular and triangular channels, annuli and rod bundles.
A Critical Review of Heat Transfer Enhancement Techniques for Use in Marine Condensers.
1982-09-01
horizontal tube, the Nusselt theory predicts that the condensate film is thinnest at the top of the tube, and thickens around the tube until at the...transfer coefficient. As pointed out above, the Nusselt analysis assumes that the condensate film drains from a horizontal tube in a continuous sheet...the condensate falling on the lower tubes does not deteriorate the thermal performance of these tubes because the helically - wrapped wires draw the
Confined Tension and Triaxial Extension Tests on Eglin High-Strength Concrete
2014-10-17
specimen were filled with Devcon 5-Minute epoxy . We encased the specimen in a liquid-tight flexible jacket to exclude the confining fluid from any...sealed to the steel endcaps with epoxy and wire clamps. Figure 3. Schematic diagram of test specimen prepared for TXE testing. TXE tests are...150 MPa – we wrapped two Kevlar jackets (0.01 in thick) around the specimen prior to installing the polyolefin jacket (0.02 in thick). The Kevlar
Intravascular migration of a broken cerclage wire into the left heart.
Leonardi, Francesco; Rivera, Fabrizio
2014-10-01
This article describes a patient in whom a broken cerclage wire migrated from the left hip into the left ventricle. A 71-year-old woman was admitted to the authors' hospital for preoperative examination before femoral hernia repair. Chest radiograph showed a metallic wire in the left ventricle. Twenty-four years earlier, she had a revision arthroplasty. During revision surgery, fragments of the osteotomy were fixed to the femur with multiple cerclage wires. During the past 5 years, radiographic follow-up showed progressive multiple ruptures of cerclage wires. The cerclage wiring was not removed because the patient had no related clinical symptoms. Radiograph of the left hip showed a well-fixed cemented acetabular ring and an uncemented femoral stem with a healed trochanteric osteotomy. All cerclage wires were broken into multiple parts, and it was very difficult to determine which part had migrated into the heart. Thoracic computed tomography scan showed wire that had migrated into the anterior left ventricular myocardial wall at the atrioventricular level. The patient had no clinical symptoms. Electrocardiogram showed a normal sinus rhythm and right bundle branch block. Because of the high risk of surgical left ventriculotomy associated with searching for wire that had migrated into the myocardial wall, patient monitoring was planned. Definitive management of this complication constitutes a dilemma. Although this complication is highly unusual, the possibility of intracardiac migration of broken wire should be considered when deciding on prophylactic surgical removal of hardware after fracture or osteotomy healing. Copyright 2014, SLACK Incorporated.
Flexible ex vivo phantoms for validation of diffusion tensor tractography on a clinical scanner.
Watanabe, Makoto; Aoki, Shigeki; Masutani, Yoshitaka; Abe, Osamu; Hayashi, Naoto; Masumoto, Tomohiko; Mori, Harushi; Kabasawa, Hiroyuki; Ohtomo, Kuni
2006-11-01
The aim of this study was to develop ex vivo diffusion tensor (DT) flexible phantoms. Materials were bundles of textile threads of cotton, monofilament nylon, rayon, and polyester bunched with spiral wrapping bands and immersed in water. DT images were acquired on a 1.5-Tesla clinical magnetic resonance scanner using echo planar imaging sequences with 15 motion probing gradient directions. DT tractography with seeding and a line-tracking method was carried out by software originally developed on a PC-based workstation. We observed relatively high fractional anisotropy on the polyester phantom and were able to reconstruct tractography. Straight tracts along the bundle were displayed when it was arranged linearly. It was easy to bend arcuately or bifurcate at one end; and tracts followed the course of the bundle, whether it was curved or branched and had good agreement with direct visual observation. Tractography with the other fibers was unsuccessful. The polyester phantom revealed a diffusion anisotropic structure according to its shape and would be utilizable repeatedly under the same conditions, differently from living central neuronal system. It would be useful to validate DT sequences and to optimize an algorithm or parameters of DT tractography software. Additionally, the flexibility of the phantom would enable us to model human axonal projections.
Rapid electron beam accelerator (REBA-tron)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kapetanakos, C.A.; Sprangle, P.A.; Dialetis, D.
1986-03-05
This invention comprises a particle accelerator with a toroidal vacuum chamber, an injector for injecting a charged-paticle beam into the chamber and an exit port to extract the accelerated particle beam. A toroidal magnetic field to confine the beam in the chamber is generated by a set of coils with their axis along the minor axis of the chamber and by two twisted wires that carry current in the same direction wrapped around the chamber. The two twisted wires also generate a torsatron magnetic field that controls the minor radius of the beam. A time-varying magnetic field is generated bymore » two concentric cylindrical plates surrounding the chamber. A convoluted transmission line generates a localized electric field in the chamber to accelerate the beam.« less
Thermodynamics of the adsorption of flexible polymers on nanowires
NASA Astrophysics Data System (ADS)
Vogel, Thomas; Gross, Jonathan; Bachmann, Michael
2015-03-01
Generalized-ensemble simulations enable the study of complex adsorption scenarios of a coarse-grained model polymer near an attractive nanostring, representing an ultrathin nanowire. We perform canonical and microcanonical statistical analyses to investigate structural transitions of the polymer and discuss their dependence on the temperature and on model parameters such as effective wire thickness and attraction strength. The result is a complete hyperphase diagram of the polymer phases, whose locations and stability are influenced by the effective material properties of the nanowire and the strength of the thermal fluctuations. Major structural polymer phases in the adsorbed state include compact droplets attached to or wrapping around the wire, and tubelike conformations with triangular pattern that resemble ideal boron nanotubes. The classification of the transitions is performed by microcanonical inflection-point analysis.
Eisen, E A; Wegman, D H; Smith, T J
1985-02-01
Pulmonary function was measured before, during, and after the end of the workshift in 83 workers in the retail food industry. All acute changes in forced expiratory volume in 1 s were standardized for lung size before the magnitude of the changes were compared between the workers exposed and unexposed to the use of hot wires for cutting plastic film. No association was found between acute drop in pulmonary function and either direct or indirect exposure in the absence of a history of asthma or allergy to inhaled materials. The borderline significance of an interaction term between exposure and asthma/allergy in a regression analysis suggests that workers with a history of asthma or atopy may have an acute response to hot-wire wrapping emissions.
Thermodynamics of the adsorption of flexible polymers on nanowires.
Vogel, Thomas; Gross, Jonathan; Bachmann, Michael
2015-03-14
Generalized-ensemble simulations enable the study of complex adsorption scenarios of a coarse-grained model polymer near an attractive nanostring, representing an ultrathin nanowire. We perform canonical and microcanonical statistical analyses to investigate structural transitions of the polymer and discuss their dependence on the temperature and on model parameters such as effective wire thickness and attraction strength. The result is a complete hyperphase diagram of the polymer phases, whose locations and stability are influenced by the effective material properties of the nanowire and the strength of the thermal fluctuations. Major structural polymer phases in the adsorbed state include compact droplets attached to or wrapping around the wire, and tubelike conformations with triangular pattern that resemble ideal boron nanotubes. The classification of the transitions is performed by microcanonical inflection-point analysis.
77 FR 65864 - North American Free-Trade Agreement (NAFTA), Article 1904 Binational Panel Reviews
Federal Register 2010, 2011, 2012, 2013, 2014
2012-10-31
..., respecting Carbon and Certain Alloy Steel Wire Rod from Canada, NAFTA Secretariat File Number USA-CDA-2008... cases. (Dongbu Steel Co. Ltd. v. United States, 635 F3d 1363 (Fed Cir. 2011); and JTEKT Corp. v. United...
Code of Federal Regulations, 2011 CFR
2011-07-01
... Standards for Hazardous Air Pollutants for Steel Pickling-HCl Process Facilities and Hydrochloric Acid... to remove residual acid. Carbon steel means steel that contains approximately 2 percent or less... equipment and tanks configured for pickling metal strip, rod, wire, tube, or pipe that is passed through an...
Code of Federal Regulations, 2010 CFR
2010-07-01
... Standards for Hazardous Air Pollutants for Steel Pickling-HCl Process Facilities and Hydrochloric Acid... to remove residual acid. Carbon steel means steel that contains approximately 2 percent or less... equipment and tanks configured for pickling metal strip, rod, wire, tube, or pipe that is passed through an...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jeong, Junseok; Choi, Ji Eun; Hong, Young Joon, E-mail: yjhong@sejong.ac.kr
Position-controlled n-ZnO microwire (MW) and nanowire-bundle (NW-B) arrays were fabricated using hydrothermal growth of ZnO on a patterned p-GaN film. Both the wire/film p–n heterojunctions showed electrical rectification features at reverse-bias (rb) voltages, analogous to backward diodes. Dichromatic electroluminescence (EL) emissions with 445- and 560-nm-wavelength peaks displayed whitish-blue and greenish-yellow light from MW- and NW-B-based heterojunctions at rb voltages, respectively. The different dichromatic EL emission colors were studied based on photoluminescence spectra and the dichromatic EL peak intensity ratios as a function of the rb voltage. The different EL colors are discussed with respect to depletion thickness and electron tunnelingmore » probability determined by wire/film junction geometry and size.« less
NASA Astrophysics Data System (ADS)
Jeong, Junseok; Choi, Ji Eun; Kim, Yong-Jin; Hwang, Sunyong; Kim, Sung Kyu; Kim, Jong Kyu; Jeong, Hu Young; Hong, Young Joon
2016-09-01
Position-controlled n-ZnO microwire (MW) and nanowire-bundle (NW-B) arrays were fabricated using hydrothermal growth of ZnO on a patterned p-GaN film. Both the wire/film p-n heterojunctions showed electrical rectification features at reverse-bias (rb) voltages, analogous to backward diodes. Dichromatic electroluminescence (EL) emissions with 445- and 560-nm-wavelength peaks displayed whitish-blue and greenish-yellow light from MW- and NW-B-based heterojunctions at rb voltages, respectively. The different dichromatic EL emission colors were studied based on photoluminescence spectra and the dichromatic EL peak intensity ratios as a function of the rb voltage. The different EL colors are discussed with respect to depletion thickness and electron tunneling probability determined by wire/film junction geometry and size.
Kirschvink, J L
1992-01-01
A common mistake in biomagnetic experimentation is the assumption that Helmholtz coils provide uniform magnetic fields; this is true only for a limited volume at their center. Substantial improvements on this design have been made during the past 140 years with systems of three, four, and five coils. Numerical comparisons of the field uniformity generated by these designs are made here, along with a table of construction details and recommendations for their use in experiments in which large volumes of uniform intensity magnetic exposures are needed. Double-wrapping, or systems of bifilar windings, can also help control for the non-magnetic effects of the electric coils used in many experiments. In this design, each coil is wrapped in parallel with two separate, adjacent strands of copper wire, rather than the single strand used normally. If currents are flowing in antiparallel directions, the magnetic fields generated by each strand will cancel and yield virtually no external magnetic field, whereas parallel currents will yield an external field. Both cases will produce similar non-magnetic effects of ohmic heating, and simple measures can reduce the small vibration and electric field differences. Control experiments can then be designed such that the only major difference between treated and untreated groups is the presence or absence of the magnetic field. Double-wrapped coils also facilitate the use of truly double-blind protocol, as the same apparatus can be used either for experimental or control groups.
Qamhieh, Khawla; Nylander, Tommy; Black, Camilla F; Attard, George S; Dias, Rita S; Ainalem, Marie-Louise
2014-07-14
This study deals with the build-up of biomaterials consisting of biopolymers, namely DNA, and soft particles, poly(amido amine) (PAMAM) dendrimers, and how to model their interactions. We adopted and applied an analytical model to provide further insight into the complexation between DNA (4331 bp) and positively charged PAMAM dendrimers of generations 1, 2, 4, 6 and 8, previously studied experimentally. The theoretical models applied describe the DNA as a semiflexible polyelectrolyte that interacts with dendrimers considered as either hard (impenetrable) spheres or as penetrable and soft spheres. We found that the number of DNA turns around one dendrimer, thus forming a complex, increases with the dendrimer size or generation. The DNA penetration required for the complex to become charge neutral depends on dendrimer generation, where lower generation dendrimers require little penetration to give charge neutral complexes. High generation dendrimers display charge inversion for all considered dendrimer sizes and degrees of penetration. Consistent with the morphologies observed experimentally for dendrimer/DNA aggregates, where highly ordered rods and toroids are found for low generation dendrimers, the DNA wraps less than one turn around the dendrimer. Disordered globular structures appear for high generation dendrimers, where the DNA wraps several turns around the dendrimer. Particularly noteworthy is that the dendrimer generation 4 complexes, where the DNA wraps about one turn around the dendrimers, are borderline cases and can form all types of morphologies. The net-charges of the aggregate have been estimated using zeta potential measurements and are discussed within the theoretical framework.
Spider wrapping silk fibre architecture arising from its modular soluble protein precursor
NASA Astrophysics Data System (ADS)
Tremblay, Marie-Laurence; Xu, Lingling; Lefèvre, Thierry; Sarker, Muzaddid; Orrell, Kathleen E.; Leclerc, Jérémie; Meng, Qing; Pézolet, Michel; Auger, Michèle; Liu, Xiang-Qin; Rainey, Jan K.
2015-06-01
Spiders store spidroins in their silk glands as high concentration aqueous solutions, spinning these dopes into fibres with outstanding mechanical properties. Aciniform (or wrapping) silk is the toughest spider silk and is devoid of the short amino acid sequence motifs characteristic of the other spidroins. Using solution-state NMR spectroscopy, we demonstrate that the 200 amino acid Argiope trifasciata AcSp1 repeat unit contrasts with previously characterized spidroins, adopting a globular 5-helix bundle flanked by intrinsically disordered N- and C-terminal tails. Split-intein-mediated segmental NMR-active isotope-enrichment allowed unambiguous demonstration of modular and malleable “beads-on-a-string” concatemeric behaviour. Concatemers form fibres upon manual drawing with silk-like morphology and mechanical properties, alongside secondary structuring and orientation consistent with native AcSp1 fibres. AcSp1 structural stability varies locally, with the fifth helix denaturing most readily. The structural transition of aciniform spidroin from a mostly α-helical dope to a mixed α-helix/β-sheet-containing fibre can be directly related to spidroin architecture and stability.
Method for fabricating multi-strand superconducting cable
Borden, A.R.
1985-04-01
Multi-strand superconducting cables adapted to be used, for example, to wind a magnet are fabricated by directing wire strands inwardly from spools disposed on the perimeter of a rotating disk and wrapping them diagonally around a tapered mandrel with a flattened cross-sectional shape with a core having a wedge-shaped channel. As the cable is pulled axially, flexibly coupled wedge-shaped pieces are continuously passed through the channel in the mandrel and inserted into the cable as an internal support therefor.
Apparatus and method for fabricating multi-strand superconducting cable
Borden, Albert R.
1986-01-01
Multi-strand superconducting cables adapted to be used, for example, to wind a magnet is fabricated by directing wire strands inwardly from spools disposed on the perimeter of a rotating disk and wrapping them diagonally around a tapered mandrel with a flattened cross-sectional shape with a core having a wedge-shaped channel. As the cable is pulled axially, flexibly coupled wedge-shaped pieces are continuously passed through the channel in the mandrel and inserted into the cable as an internal support therefor.
Reduced graphene oxide wrapped Ag nanostructures for enhanced SERS activity
NASA Astrophysics Data System (ADS)
Nair, Anju K.; Kala, M. S.; Thomas, Sabu; Kalarikkal, Nandakumar
2018-04-01
Graphene - metal nanoparticle hybrids have received great attention due to their unique electronic properties, large specific surface area, very high conductivity and more charge transfer. Thus, it is extremely advantages to develop a simple and efficient process to disperse metal nanostructures over the surface of graphene sheets. Herein, we report a hydrothermal assisted strategy for developing reduced graphene oxide /Ag nanomorphotypes (cube, wire) for surface enhanced Raman scattering (SERS) applications, considering the advantages of synergistic effect of graphene and plasmonic properties of Ag nanomorphotypes.
Electrolytic Reduction of Titania Slag in Molten Calcium Chloride Bath
NASA Astrophysics Data System (ADS)
Mohanty, Jayashree
2012-05-01
Ferro-titanium is prepared by direct electrolytic reduction of titania-rich slag obtained from plasma smelting of ilmenite in molten CaCl2. The product after electro-reduction is characterized by x-ray diffraction, scanning electron microscopy, and electron probe microanalysis. The electrolysis is carried out at a cell voltage of 3.0 V, taking graphite as the electrolysis cell as well as the anode, and a titania-rich slag piece wrapped by a nichrome wire is used as the cathode.
NASA Technical Reports Server (NTRS)
Kahan, A. M. (Principal Investigator)
1975-01-01
The author has identified the following significant results. The LANDSAT data collection system has proven itself to be a valuable tool for control of cloud seeding operations and for verification of weather forecasts. These platforms have proven to be reliable weather resistant units suitable for the collection of hydrometeorological data from remote severe weather environments. The detailed design of the wind speed and direction system and the wire-wrapping of the logic boards were completed.
Wireless power transfer magnetic couplers
Wu, Hunter; Gilchrist, Aaron; Sealy, Kylee
2016-01-19
A magnetic coupler is disclosed for wireless power transfer systems. A ferrimagnetic component is capable of guiding a magnetic field. A wire coil is wrapped around at least a portion of the ferrimagnetic component. A screen is capable of blocking leakage magnetic fields. The screen may be positioned to cover at least one side of the ferrimagnetic component and the coil. A distance across the screen may be at least six times an air gap distance between the ferrimagnetic component and a receiving magnetic coupler.
The performance of cable braids and terminations to lightning induced transients
NASA Technical Reports Server (NTRS)
Crofts, David
1991-01-01
The latest specification detailing the test waveforms for indirect lightning transients as applied to aircraft wiring systems specify very high voltages and currents. Although considerable data exists for measuring cable screen leakage using such methods as surface transfer impedance and bulk cable injection, there is little data on the likely core transient level that is likely to be induced from these threats. In particular, the new Waveform 5 at very high current levels (10 kA) is reputed to cause severe cable damage. A range of representative cables were made with various screen termination techniques and screening levels. These were tested first to determine their relative screening performance and then they were subjected to lightning transient testing to all the specified waveforms. Core voltages were measured for each test. Tests were also performed on bundles with fewer wires to determine the failure criteria with Waveform 5 and these tests also include flat conductor cables. The test showed that correctly terminated cable bundles performed well in all the tests and would provide a high level of protection to the electronic systems. The use of overbraides, provided the individual screens are well terminated, appears to be unnecessary.
NASA Astrophysics Data System (ADS)
Dang, Lingyan; Tian, Chen; Zhao, Shifeng; Lu, Qingshan
2018-06-01
Barium and manganese-doped zinc silicates was prepared under hydrothermal treatment by mesoporous template route employing mesoporous silica as an active template. The sample displays a rod-like morphology with a mean diameter of ∼40 nm and a mean length of ∼450 nm, which inherits the characteristics of mesoporous silica. The individual rods show single crystalline and assemble into bundle-like hierarchical structure along the channels of the mesoporous silica. When barium ions together with manganese ions are co-doped in zinc silicate, the green emission corresponding to manganese ions display a significant enhancement, especially for the sample with the barium doping concentration of 0.08, which indicates that an energy transfer from barium to manganese ions takes place. With further increasing barium concentration from 0.08 to 0.10, the recombination between the defects related to barium and the excitation states of the manganese dominates accompanying non-radiative transitions which can reduce the emission efficiency.
Zinc oxide nano-rods based glucose biosensor devices fabrication
NASA Astrophysics Data System (ADS)
Wahab, H. A.; Salama, A. A.; El Saeid, A. A.; Willander, M.; Nur, O.; Battisha, I. K.
2018-06-01
ZnO is distinguished multifunctional material that has wide applications in biochemical sensor devices. For extracellular measurements, Zinc oxide nano-rods will be deposited on conducting plastic substrate with annealing temperature 150 °C (ZNRP150) and silver wire with annealing temperature 250 °C (ZNRW250), for the extracellular glucose concentration determination with functionalized ZNR-coated biosensors. It was performed in phosphate buffer saline (PBS) over the range from 1 μM to 10 mM and on human blood plasma. The prepared samples crystal structure and surface morphologies were characterized by XRD and field emission scanning electron microscope FESEM respectively.
Epitaxial growth of quantum rods with high aspect ratio and compositional contrast
DOE Office of Scientific and Technical Information (OSTI.GOV)
Li, L. H.; Patriarche, G.; Fiore, A.
2008-12-01
The epitaxial growth of quantum rods (QRs) on GaAs was investigated. It was found that GaAs thickness in the GaAs/InAs superlattice used for QR formation plays a key role in improving the QR structural properties. Increasing the GaAs thickness results in both an increased In compositional contrast between the QRs and surrounding layer, and an increased QR length. QRs with an aspect ratio of up to 10 were obtained, representing quasiquantum wires in a GaAs matrix. Due to modified confinement and strain potential, such nanostructure is promising for controlling gain polarization.
Funerary artifacts, social status, and atherosclerosis in ancient peruvian mummy bundles.
Sutherland, M Linda; Cox, Samantha L; Lombardi, Guido P; Watson, Lucia; Valladolid, Clide M; Finch, Caleb E; Zink, Albert; Frohlich, Bruno; Kaplan, Hillard S; Michalik, David E; Miyamoto, Michael I; Allam, Adel H; Thompson, Randall C; Wann, L Samuel; Narula, Jagat; Thomas, Gregory S; Sutherland, James D
2014-06-01
Evidence of atherosclerotic plaques in ancient populations has led to the reconsideration of risk factors for heart disease and of the common belief that it is a disease of modern times. Fifty-one wrapped mummy bundles excavated from the sites of Huallamarca, Pedreros, and Rinconada La Molina from the Puruchuco Museum collection in Lima, Peru, were scanned using computed tomography to investigate the presence of atherosclerosis. Funerary artifacts contained within the undisturbed mummy bundles were analyzed as an attempt to infer the social status of the individuals to correlate social status with evidence of heart disease in this ancient Peruvian group. This work also provides an inventory of the museum mummy collection to guide and facilitate future research. Statistical analysis concluded that there is little association between the types of grave goods contained within the bundles when the groups are pooled together. However, some patterns of artifact type, material, atherosclerosis, and sex emerge when the 3 excavation sites are analyzed separately. From the current sample, it would seem that social class is difficult to discern, but those from Huallamarca have the most markers of elite status. We had hypothesized that higher-status individuals may have had lifestyles that would place them at a higher risk for atherogenesis. There seems to be some indication of this within the site of Huallamarca, but it is inconclusive in the other 2 archeological sites. It is possible that a larger sample size in the future could reveal more statistically significant results. Copyright © 2014. Published by Elsevier B.V.
NASA Astrophysics Data System (ADS)
Kuang, K. S. C.; Cantwell, W. J.
2003-08-01
This paper reports the use of a plastic fibre sensor for detecting impact damage in carbon fibre epoxy cantilever beams by monitoring their damping response under free vibration loading conditions. The composite beams were impacted at impact energies up to 8 J. The residual strengths and stiffnesses of the damaged laminates were measured in order to relate reductions in their mechanical properties to changes in their damping characteristics. Here, optical fibre sensors were surface bonded to carbon fibre composite beams which were subjected to free vibration tests to monitor their dynamic response. In the second part of this study, Ni-Ti shape memory alloy (SMA) wires were employed to control and modify the damping response of a composite beam. The SMA wires were initially trained to obtain the desired shape when activated. Here, the trained SMA wires were heated locally using a nickel/chromium wire that was wrapped around the trained region of the SMA. By using this method to activate the SMA wire (as opposed to direct electrical heating), it is possible to obtain localized actuation without heating the entire length of the wire. This procedure minimizes any damage to the host material that may result from local heat transfer between the SMA wire and the composite structure. In addition, the reduction in power requirements to achieve SMA activation permits the use of small-size power packs which can in turn lead to a potential weight reduction in weight-critical applications. The findings of this study demonstrate that a trained SMA offers a superior damping capability to that exhibited by an 'as-supplied' flat-annealed wire.
Transvenous pacemaker electrodes placed unintentionally in the left ventricle: three cases.
Winner, S. J.; Boon, N. A.
1989-01-01
Three patients are described in whom pacemaker electrodes were unintentionally placed within the left ventricle, followed by considerable delay before the error was recognized. In two cases temporary pacemaker wires were inserted into the subclavian artery and passed along a retrograde course. One patient required urgent surgery for acute arterial obstruction on removal of the wire. In the third case, a permanent wire was inserted correctly into a vein but traversed the atrial septum, probably via a patent foramen ovale, to enter the left ventricle. Twelve lead electrocardiograms in all three patients showed paced complexes with right bundle branch block configuration. This appearance should raise suspicion that the pacemaker electrode might be in the left ventricle, in which case its position should be defined by chest radiographs (including a lateral view) and echocardiography. Images Figure 1 Figure 3 Figure 4 PMID:2780472
Lightning effects on the NASA F-8 digital-fly-by-wire airplane
NASA Technical Reports Server (NTRS)
Plumer, J. A.; Fisher, F. A.; Walko, L. C.
1975-01-01
The effects of lightning on a Digital Fly-By-Wire (DFBW)aircraft control system were investigated. The aircraft was a NASA operated F-8 fitted with a modified Apollo guidance computer. Current pulses similar in waveshape to natural lightning, but lower in amplitude, were injected into the aircraft. Measurements were made of the voltages induced on the DFBW circuits, the total current induced on the bundles of wires, the magnetic field intensity inside the aircraft, and the current density on the skin of the aircraft. Voltage measurements were made in both the line-to-ground and line-to-line modes. Voltages measured at the non-destructive test level were then scaled upward to determine how much would be produced by actual lightning. A 200,000 ampere severe lightning flash would produce between 40 and 2000 volts in DFBW circuits. Some system components are expected to be vulnerable to these voltages.
Thermodynamics of the adsorption of flexible polymers on nanowires
Vogel, Thomas; Gross, Jonathan; Bachmann, Michael
2015-03-09
Generalized-ensemble simulations enable the study of complex adsorption scenarios of a coarse-grained model polymer near an attractive nanostring, representing an ultrathin nanowire. We perform canonical and microcanonical statistical analyses to investigate structural transitions of the polymer and discuss their dependence on the temperature and on model parameters such as effective wire thickness and attraction strength. The result is a complete hyperphase diagram of the polymer phases, whose locations and stability are influenced by the effective material properties of the nanowire and the strength of the thermal fluctuations. Major structural polymer phases in the adsorbed state include compact droplets attached tomore » or wrapping around the wire, and tubelike conformations with triangular pattern that resemble ideal boron nanotubes. In conclusion, the classification of the transitions is performed by microcanonical inflection-point analysis.« less
Recent developments in BWR fuel design
DOE Office of Scientific and Technical Information (OSTI.GOV)
Congdon, S.P.; Noble, L.D.; Wood, J.E.
1991-11-01
Substantial increases in the cost effectiveness and performance capability of boiling water reactor (BWR) fuel designs have been implemented in the past 5 to 7 yr. This increase has been driven by (a) utility desires to lower fuel and operating costs and (b) design innovations that have lowered enrichment requirements, improved thermal-hydraulic performance, and increased discharge exposure. Higher discharge exposures reduce disposal costs for European and Asian utilities and enable US utilities to lengthen operating cycles. A typical BWR reload fuel bundle fabricated today has 25% higher {sup 235}U enrichment and a factor of 2 higher gadolinium loading than onemore » made several years ago. Today's BWR fuel bundles also contain more unheated water reduces the axial water density variation, lowers the void coefficient, and enhances the neutron efficiency of the bundle, reducing both the gadolinium poison and the enrichment requirements. In addition to these general trends, the following unique design innovations have further enhanced the fuel cost efficiency and performance characteristics of BWR fuel: ferrule spacer, part length rods, interactive channel, and bundle enhanced spectral shift. GE's fuel designs offer the flexibility for modern BWR fuel requirements and contain unique design features that enhance flexibility for modern BWR fuel requirements and contain unique design features that enhance flexibility and fuel cycle economics.« less
Analysis and Evaluation of the Dynamic Performance of SMA Actuators for Prosthetic Hand Design
NASA Astrophysics Data System (ADS)
O'Toole, Kevin T.; McGrath, Mark M.; Coyle, Eugene
2009-08-01
It is widely acknowledged within the biomedical engineering community that shape memory alloys (SMAs) exhibit great potential for application in the actuation of upper limb prosthesis designs. These lightweight actuators are particularly suitable for prosthetic hand solutions. A four-fingered, 12 degree-of-freedom prosthetic hand has been developed featuring SMA bundle actuators embedded within the palmar structure. Joule heating of the SMA bundle actuators generates sufficient torque at the fingers to allow a wide range of everyday tasks to be carried out. Transient characterization of SMA bundles has shown that performance/response during heating and cooling differs substantially. Natural convection is insufficient to provide for adequate cooling during elongation of the actuators. An experimental test-bed has been developed to facilitate analysis of the heat transfer characteristics of the appropriately sized SMA bundle actuators for use within the prosthetic hand design. Various modes of heat sinking are evaluated so that the most effective wire-cooling solution can be ascertained. SMA bundles of varying size will be used so that a generalized model of the SMA displacement performance under natural and forced cooling conditions can be obtained. The optimum cooling solution will be implemented onto the mechanical hand framework in future work. These results, coupled with phenomenological models of SMA behavior, will be used in the development of an effective control strategy for this application in future work.
Apparatus and method for pulsed laser deposition of materials on wires and pipes
Fernandez, Felix E.
2003-01-01
Methods and apparatuses are disclosed which allow uniform coatings to be applied by pulsed laser deposition (PLD) on inner and outer surfaces of cylindrical objects, such as rods, pipes, tubes, and wires. The use of PLD makes this technique particularly suitable for complex multicomponent materials, such as superconducting ceramics. Rigid objects of any length, i.e., pipes up to a few meters, and with diameters from less than 1 centimeter to over 10 centimeters can be coated using this technique. Further, deposition is effected simultaneously onto an annular region of the pipe wall. This particular arrangement simplifies the apparatus, reduces film uniformity control difficulties, and can result in faster operation cycles. In addition, flexible wires of any length can be continuously coated using the disclosed invention.
Gluteal muscle attachment during proximal femoral reconstruction in a canine model.
Pluhar, G Elizabeth; Manley, Paul A; Heiner, John P; Vanderby, Ray; Markel, Mark D
2007-02-01
In this 18 month in vivo canine study we compared three methods of attaching the gluteal muscles to the proximal femur during hip reconstruction with an allograft-prosthesis composite (APC). All three methods are commonly practiced in human hip revision surgery and data on their effectiveness in dogs is directly relevant to human treatment. The methods compared were host gluteal tendon sutured to allograft tendon, host greater trochanter apposed to allograft using a cable grip system, and host cortical bone shells around the allograft secured with cerclage wires. For each method, we assessed changes in allograft-host bone fusion, weight bearing, gluteal muscle mass, and structural properties through qualitative radiography, gait analysis, histology, and biomechanical testing. Hip reconstruction using the WRAP method resulted in the greatest limb use with complete resolution of gluteal muscle atrophy 18 months after surgery. This method yielded a stronger, more stable hip joint that allowed for more normal limb function. These hips had the more rapid rate of bony union at the host bone-allograft junction and little resorption of the graft. The increased limb use and resultant larger gluteal muscle mass conferred to the WRAP hip composites the greatest tensile strength and stiffness when tested 18 months after reconstruction. There was a large amount of new bone formation on the periosteal surface where the WRAP reconstructions had an overlay of live bone that resulted in a more rapid union and increased cortical width at the level of the osteotomy. New bone also penetrated into the allograft a greater distance from the osteotomy in the WRAP group.
Rigatelli, G L; Carraro, U; Barbiero, M; Zanchetta, M; Rigatelli, G
2002-02-01
There are no data regarding real cardiac assistance in demand dynamic cardiomyoplasty (DDCMP). A test of the use of Doppler flow wire is presented to demonstrate cardiac assistance in DDCMP. Comparative study in hospitalized care. A peripheral Flex Doppler flow wire of 0.018 inch was advanced through a 4F introducer femoral arterial in seven DDCMP patients (age=57.1+/-6.2 years; NYHA= 1.4+/-0.5). A short period of 10 sec with stimulator off and a following period of 15 sec with clinical stimulation were recorded. We measured the maximum peak aortic flow velocity (MPAV) in all beats. Latissimus dorsi (LD) mechanogram was simultaneously recorded. Statistical analysis showed an increase not only in MPAV in assisted period versus rest, but also in assisted beats versus unassisted (8.42+/-6.98% and 7.55+/-3.07%). Intravascular Doppler proved real systolic assistance in DDCMP; in DDCMP systolic assistance is correlated to the LD wrap speed of contraction, suggesting that demand stimulation could be the most effective protocol in dynamic cardiomyoplasty.
Lord, D.E.; Carter, G.W.; Petrini, R.R.
1983-08-02
A video flowmeter is described that is capable of specifying flow nature and pattern and, at the same time, the quantitative value of the rate of volumetric flow. An image of a determinable volumetric region within a fluid containing entrained particles is formed and positioned by a rod optic lens assembly on the raster area of a low-light level television camera. The particles are illuminated by light transmitted through a bundle of glass fibers surrounding the rod optic lens assembly. Only particle images having speeds on the raster area below the raster line scanning speed may be used to form a video picture which is displayed on a video screen. The flowmeter is calibrated so that the locus of positions of origin of the video picture gives a determination of the volumetric flow rate of the fluid. 4 figs.
Design and fabrication of a three-finger prosthetic hand using SMA muscle wires
NASA Astrophysics Data System (ADS)
Simone, Filomena; York, Alexander; Seelecke, Stefan
2015-03-01
Bio-inspired hand-like gripper systems based on shape memory alloy (SMA) wire actuation have the potential to enable a number of useful applications in, e.g., the biomedical field or industrial assembly systems. The inherent high energy density makes SMA solutions a natural choice for systems with lightweight, low noise and high force requirements, such as hand prostheses or robotic systems in a human/machine environment. The focus of this research is the development, design and realization of a SMA-actuated prosthetic hand prototype with three fingers. The use of thin wires (100 μm diameter) allows for high cooling rates and therefore fast movement of each finger. Grouping several small wires mechanically in parallel allows for high force actuation. To save space and to allow for a direct transmission of the motion to each finger, the SMA wires are attached directly within each finger, across each phalanx. In this way, the contraction of the wires will allow the movement of the fingers without the use of any additional gears. Within each finger, two different bundles of wires are mounted: protagonist ones that create bending movement and the antagonist ones that enable stretching of each phalanx. The resistance change in the SMA wires is measured during actuation, which allows for monitoring of the wire stroke and potentially the gripping force without the use of additional sensors. The hand is built with modern 3D-printing technologies and its performance while grasping objects of different size and shape is experimentally investigated illustrating the usefulness of the actuator concept.
NASA Technical Reports Server (NTRS)
1985-01-01
Extensive computer based engineering design effort resulted in optimization of a superconducting magnet design with an average bulk current density of approximately 12KA/cm(2). Twisted, stranded 0.0045 inch diameter NbTi superconductor in a copper matrix was selected. Winding the coil from this bundle facilitated uniform winding of the small diameter wire. Test coils were wound using a first lot of the wire. The actual packing density was measured from these. Interwinding voltage break down tests on the test coils indicated the need for adjustment of the wire insulation on the lot of wire subsequently ordered for construction of the delivered superconducting magnet. Using the actual packing densities from the test coils, a final magnet design, with the required enhancement and field profile, was generated. All mechanical and thermal design parameters were then also fixed. The superconducting magnet was then fabricated and tested. The first test was made with the magnet immersed in liquid helium at 4.2K. The second test was conducted at 2K in vacuum. In the latter test, the magnet was conduction cooled from the mounting flange end.
Optimum Construction of Heating Coil for Domestic Induction Cooker
NASA Astrophysics Data System (ADS)
Sinha, Dola; Bandyopadhyay, Atanu; Sadhu, Pradip Kumar; Pal, Nitai
2010-10-01
The design and optimization of the parameters of heating coil is very important for the analytical analysis of high frequency inverter fed induction cooker. Moreover, accurate prediction of high frequency winding loss (i.e., losses due to skin and proximity effects) is necessary as the induction cooker used in power electronics applications. At high frequency current penetration in the induction coil circuit is very difficult for conducting wire due to skin-effect. To eradicate the skin effect heating coil is made up of bundle conductor i.e., litz wire. In this paper inductances and AC resistances of a litz-wire are calculated and optimized by considering the input parameters like wire type, shape, number of strand, number of spiral turn, number of twist per feet of heating coil and operating frequency. A high frequency half bridge series resonant mirror inverter circuit is used in this paper and taking the optimum values of inductance and ac resistance the circuit is simulated through PSPICE simulations. It has been noticed that the results are feasible enough for real implementation.
78 FR 33063 - Initiation of Five-Year (“Sunset”) Review
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...-Year Review which covers the same orders. DATES: Effective Date: June 1, 2013. FOR FURTHER INFORMATION... Case No. Country Product Department contact A-351-832 731-TA-953....... Brazil Carbon and Certain Jennifer Moats Alloy Steel Wire Rod (202) 482-5047 (2nd Review). C-351-833 701-TA-417....... Brazil Carbon...
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2012-07-01
... achievable (BAT). 420.93 Section 420.93 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... application of the best available technology economically achievable (BAT). Except as provided in 40 CFR 125... rinse waters)—(1) Rod, wire and coil. Subpart I Pollutant or pollutant property BAT effluent limitations...
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2014-07-01
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2011-07-01
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2010-07-01
... achievable (BAT). 420.93 Section 420.93 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... application of the best available technology economically achievable (BAT). Except as provided in 40 CFR 125... rinse waters)—(1) Rod, wire and coil. Subpart I Pollutant or pollutant property BAT effluent limitations...
Q-Switched and Mode Locked Short Pulses from a Diode Pumped, YB-Doped Fiber Laser
2009-03-26
a rod-type photonic crystal fiber [14]. Commercial pulsed fiber laser systems currently offered by Polar Onyx range from 1-10 W, with pulse... Onyx , Fiber laser products http://www.polaronyx.com/Uranus_introduction.htm . 20. Business Wire Press Release, “SPI Lasers 30W pulsed fiber laser
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Threaded average temperature thermocouple
NASA Technical Reports Server (NTRS)
Ward, Stanley W. (Inventor)
1990-01-01
A threaded average temperature thermocouple 11 is provided to measure the average temperature of a test situs of a test material 30. A ceramic insulator rod 15 with two parallel holes 17 and 18 through the length thereof is securely fitted in a cylinder 16, which is bored along the longitudinal axis of symmetry of threaded bolt 12. Threaded bolt 12 is composed of material having thermal properties similar to those of test material 30. Leads of a thermocouple wire 20 leading from a remotely situated temperature sensing device 35 are each fed through one of the holes 17 or 18, secured at head end 13 of ceramic insulator rod 15, and exit at tip end 14. Each lead of thermocouple wire 20 is bent into and secured in an opposite radial groove 25 in tip end 14 of threaded bolt 12. Resulting threaded average temperature thermocouple 11 is ready to be inserted into cylindrical receptacle 32. The tip end 14 of the threaded average temperature thermocouple 11 is in intimate contact with receptacle 32. A jam nut 36 secures the threaded average temperature thermocouple 11 to test material 30.
Charge transport through molecular rods with reduced pi-conjugation.
Lörtscher, Emanuel; Elbing, Mark; Tschudy, Meinrad; von Hänisch, Carsten; Weber, Heiko B; Mayor, Marcel; Riel, Heike
2008-10-24
A series of oligophenylene rods of increasing lengths is synthesized to investigate the charge-transport mechanisms. Methyl groups are attached to the phenyl rings to weaken the electronic overlap of the pi-subsystems along the molecular backbones. Out-of-plane rotation of the phenyl rings is confirmed in the solid state by means of X-ray analysis and in solution by using UV/Vis spectroscopy. The influence of the reduced pi-conjugation on the resonant charge transport is studied at the single-molecule level by using the mechanically controllable break-junction technique. Experiments are performed under ultra-high-vacuum conditions at low temperature (50 K). A linear increase of the conductance gap with increasing number of phenyl rings (from 260 meV for one ring to 580 meV for four rings) is revealed. In addition, the absolute conductance of the first resonant peaks does not depend on the length of the molecular wire. Resonant transport through the first molecular orbital is found to be dominated by charge-carrier injection into the molecule, rather than by the intrinsic resistance of the molecular wire length.
The use of sublaminar cables to replace Luque wires.
Songer, M N; Spencer, D L; Meyer, P R; Jayaraman, G
1991-08-01
Sublaminar wires have been used in conjunction with posterior instrumentation to stabilize the spine. Sublaminar wiring has fallen into disfavor because of an increase in neurologic complications with the Luque technique as well as wire breakage, dural tears, and difficulty of removal. A cable system consisting of two 49-stranded stainless steel cables connected to one malleable leader was designed to overcome these shortcomings. Biomechanical testing revealed that the maximum yield strength of a single stainless steel cable loop was 2.85-2.94 times greater than a double 0.05-in. stainless steel wire loop. The fatigue tests demonstrated that the stainless steel cables required 6-22 times more cycles to failure than the stainless steel wire. Many of the titanium cables failed immediately under higher loads (0-100 lb) because of slipping of the crimp. The preliminary clinical results after a mean of 19 months of follow-up of 245 cables are encouraging. There has been no breakage or loosening of the cables and no complications associated with the use of the cables. The stainless steel cables are very strong, but more important, the cable flexibility prevents repeated contusions to the spinal cord during insertion of the rods and tightening of wires. The cable conforms to the undersurface of the lamina. This may lead to a decrease in neurologic complications.
NASA Astrophysics Data System (ADS)
Yuguchi, Y.; Urakawa, H.; Kajiwara, K.; Draget, K. I.; Stokke, B. T.
2000-10-01
Gelation was observed by time-resolved small-angle X-ray scattering and rheology on 10 mg/ml Ca-alginate gels prepared by in situ release of Ca 2+ from CaEGTA or CaCO 3 with total Ca 2+ concentration in the range 10-20 mM. This was carried out for alginates having a fraction of α- L-GulA (G) of FG=0.39 and 0.68, respectively, obtained by the selection of alginates isolated from two different brown algae, Ascophyllum nodosum and Laminaria hyperborea stipe. Correlation between the rheological data and SAXS data shows that a large fraction of the lateral association precedes the formation of a continuous network through the sample cell. Following the initial association of chain segments in junction zones, the analysis using two-component broken rod model indicates the formation of larger bundles, and that the relative weight of these bundles increases with increasing time. The molecular model for the bundles is proposed by associating 2-16 units (G-blocks) composed of 14 (1→4) linked residues of α- L-GulA in parallel according to the available crystallographic data. The storage modulus increases as the bundles composed of associated alginate chains grow during the gel formation. The gel elasticity is mainly sustained by single chains in the alginate sample with a low fraction of α- L-GulA. The alginates with a high fraction of α- L-GulA associate into thicker bundles which join to form a network. Here the gel elasticity seems to be due to the flexible joints between bundles, since the fraction of single chains is extremely low.
Checkerboard seed-blanket thorium fuel core concepts for heavy water moderated reactors
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bromley, B.P.; Hyland, B.
2013-07-01
New reactor concepts to implement thorium-based fuel cycles have been explored to achieve maximum resource utilization. Pressure tube heavy water reactors (PT-HWR) are highly advantageous for implementing the use of thorium-based fuels because of their high neutron economy and on-line re-fuelling capability. The use of heterogeneous seed-blanket core concepts in a PT-HWR where higher-fissile-content seed fuel bundles are physically separate from lower-fissile-content blanket bundles allows more flexibility and control in fuel management to maximize the fissile utilization and conversion of fertile fuel. The lattice concept chosen was a 35-element bundle made with a homogeneous mixture of reactor grade Pu (aboutmore » 67 wt% fissile) and Th, and with a central zirconia rod to help reduce coolant void reactivity. Several checkerboard heterogeneous seed-blanket core concepts with plutonium-thorium-based fuels in a 700-MWe-class PT-HWR were analyzed, using a once-through thorium (OTT) cycle. Different combinations of seed and blanket fuel were tested to determine the impact on core-average burnup, fissile utilization, power distributions, and other performance parameters. It was found that various checkerboard core concepts can achieve a fissile utilization that is up to 26% higher than that achieved in a PT-HWR using more conventional natural uranium fuel bundles. Up to 60% of the Pu is consumed; up to 43% of the energy is produced from thorium, and up to 303 kg/year of Pa-233/U-233/U-235 are produced. Checkerboard cores with about 50% of low-power blanket bundles may require power de-rating (65% to 74%) to avoid exceeding maximum limits for channel and bundle powers and linear element ratings. (authors)« less
Annular seed-blanket thorium fuel core concepts for heavy water moderated reactors
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bromley, B.P.; Hyland, B.
2013-07-01
New reactor concepts to implement thorium-based fuel cycles have been explored to achieve maximum resource utilization. Pressure tube heavy water reactors (PT-HWR) are highly advantageous for implementing the use of thorium-based fuels because of their high neutron economy and on-line re-fuelling capability. The use of heterogeneous seed-blanket core concepts in a PT-HWR where higher-fissile-content seed fuel bundles are physically separate from lower-fissile-content blanket bundles allows more flexibility and control in fuel management to maximize the fissile utilization and conversion of fertile fuel. The lattice concept chosen is a 35-element bundle made with a homogeneous mixture of reactor grade Pu andmore » Th, and with a central zirconia rod to help reduce coolant void reactivity. Several annular heterogeneous seed-blanket core concepts with plutonium-thorium-based fuels in a 700-MWe-class PT-HWR were analyzed, using a once-through thorium (OTT) cycle. Different combinations of seed and blanket fuel were tested to determine the impact on core-average burnup, fissile utilization, power distributions, and other performance parameters. It was found that the various core concepts can achieve a fissile utilization that is up to 30% higher than is currently achieved in a PT-HWR using conventional natural uranium fuel bundles. Up to 67% of the Pu is consumed; up to 43% of the energy is produced from thorium, and up to 363 kg/year of U-233 is produced. Seed-blanket cores with ∼50% content of low-power blanket bundles may require power de-rating (∼58% to 65%) to avoid exceeding maximum limits for peak channel power, bundle power and linear element ratings. (authors)« less
NASA Astrophysics Data System (ADS)
Schmidt, F.
1980-11-01
The components of a superconducting 110 kV ac cable for power ratings or = 2000 MVA were developed. The cable design is of the semiflexible type, with a rigid cryogenic envelope containing a flexible hollow coaxial cable core. The cable core consists of spirally wound Nb-A1 composite wires electrically insulated by high pressure polyethylene tape wrappings. A 35 m long single phase test cable with full load terminals rated at 110 kV and 10 kA was constructed and successfully tested. The results obtained prove the technical feasibility and capability of this cable design.
The first resection of an aortic aneurysm.
Ellis, Harold
2008-02-01
The report of the first successful resection of an abdominal aortic aneurysm, carried out in Paris in 1951, greatly influenced surgeons throughout the world who, until then, had regarded such an operation as probably being outside the bounds of surgical removal and vascular reconstruction. I well remember as a young surgeon reading of attempts to control such aneurysms by wrapping them in cellophane, or introducing coils of wire into them to induce thrombosis and I was familiar with having to stand by hopelessly as patients exsanguinated when their aneurysms ruptured.
1988-04-01
commercially for conventional surface resistivity measure- ments. Lead or copper wire wrapped around an insulating cable is used for the downhole...3 x 106 -- Igneous rocks, basic Augite porphyry Kola Peninsula 9.5-12.6 105-107 Dry Basalt Berestovetskoe 15.6 5 x 10 5 Dry Basalt Kutai 10.3 5 x...acidic Granite Azerbaidjan 3.0 x 107 -- Granite Ubinskoe 0.36 x 109 3.2 x 1018 Granite Kola Peninsula 0.16 x 105 0.3 x 1016 Granite porphyry 4.5 x 10 5
Electrical termination techniques
NASA Technical Reports Server (NTRS)
Oakey, W. E.; Schleicher, R. R.
1976-01-01
A technical review of high reliability electrical terminations for electronic equipment was made. Seven techniques were selected from this review for further investigation, experimental work, and preliminary testing. From the preliminary test results, four techniques were selected for final testing and evaluation. These four were: (1) induction soldering, (2) wire wrap, (3) percussive arc welding, and (4) resistance welding. Of these four, induction soldering was selected as the best technique in terms of minimizing operator errors, controlling temperature and time, minimizing joint contamination, and ultimately producing a reliable, uniform, and reusable electrical termination.
Whiteman, Ineka T; Gervasio, Othon L; Cullen, Karen M; Guillemin, Gilles J; Jeong, Erica V; Witting, Paul K; Antao, Shane T; Minamide, Laurie S; Bamburg, James R; Goldsbury, Claire
2009-10-14
In Alzheimer's disease (AD), rod-like cofilin aggregates (cofilin-actin rods) and thread-like inclusions containing phosphorylated microtubule-associated protein (pMAP) tau form in the brain (neuropil threads), and the extent of their presence correlates with cognitive decline and disease progression. The assembly mechanism of these respective pathological lesions and the relationship between them is poorly understood, yet vital to understanding the causes of sporadic AD. We demonstrate that, during mitochondrial inhibition, activated actin-depolymerizing factor (ADF)/cofilin assemble into rods along processes of cultured primary neurons that recruit pMAP/tau and mimic neuropil threads. Fluorescence resonance energy transfer analysis revealed colocalization of cofilin-GFP (green fluorescent protein) and pMAP in rods, suggesting their close proximity within a cytoskeletal inclusion complex. The relationship between pMAP and cofilin-actin rods was further investigated using actin-modifying drugs and small interfering RNA knockdown of ADF/cofilin in primary neurons. The results suggest that activation of ADF/cofilin and generation of cofilin-actin rods is required for the subsequent recruitment of pMAP into the inclusions. Additionally, we were able to induce the formation of pMAP-positive ADF/cofilin rods by exposing cells to exogenous amyloid-beta (Abeta) peptides. These results reveal a common pathway for pMAP and cofilin accumulation in neuronal processes. The requirement of activated ADF/cofilin for the sequestration of pMAP suggests that neuropil thread structures in the AD brain may be initiated by elevated cofilin activation and F-actin bundling that can be caused by oxidative stress, mitochondrial dysfunction, or Abeta peptides, all suspected initiators of synaptic loss and neurodegeneration in AD.
2007-12-30
KENNEDY SPACE CENTER, FLA. -- At Launch Pad 39A, a team of external tank specialists from Lockheed Martin and the United Space Alliance undertakes the task of removing the hydrogen feed-through connector in support of space shuttle Atlantis' STS-122 mission. Here, technicians wrap the connector for transport to NASA's Marshall Space Flight Center in Huntsville, Ala., for further cryogenic testing. Some of the tank's engine cutoff sensors, or ECO sensors, failed during propellant tanking for launch attempts on Dec. 6 and Dec. 9. Results of a tanking test on Dec. 18 pointed to an open circuit in the feed-through connector wiring, which is located at the base of the tank. The feed-through connector passes the wires from the inside of the tank to the outside. After the data from additional testing on the connector is analyzed, shuttle program managers will decide on a forward plan. Launch of STS-122 is targeted for January 2008. Photo credit: NASA/George Shelton
2007-12-30
KENNEDY SPACE CENTER, FLA. -- At Launch Pad 39A, a team of external tank specialists from Lockheed Martin and the United Space Alliance undertakes the task of removing the hydrogen feed-through connector in support of space shuttle Atlantis' STS-122 mission. Here, technicians wrap the connector for transport to NASA's Marshall Space Flight Center in Huntsville, Ala., for further cryogenic testing. Some of the tank's engine cutoff sensors, or ECO sensors, failed during propellant tanking for launch attempts on Dec. 6 and Dec. 9. Results of a tanking test on Dec. 18 pointed to an open circuit in the feed-through connector wiring, which is located at the base of the tank. The feed-through connector passes the wires from the inside of the tank to the outside. After the data from additional testing on the connector is analyzed, shuttle program managers will decide on a forward plan. Launch of STS-122 is targeted for January 2008. Photo credit: NASA/George Shelton
A study of tape adhesive strength on endotracheal tubes.
Fenje, N; Steward, D J
1988-03-01
A method of assessing the adhesive bond of tapes used to secure endotracheal (ET) tubes is described. Five kinds of tape and six different ET tubes including two silicone rubber, wire-reinforced tubes were tested. There are significant differences in the adhesive strength of different tapes, and in the adhesive bond formed by different ET tube materials. On the Portex clear ET tube, silk tape adhered best (p less than 0.001), followed by waterproof, cloth, dermiclear, and micropore tapes. Adhesive bonding by silk tape was significantly greater (p less than 0.001) for the three clear ET tubes (Portex clear, NCC clear, and Portex ivory) than for the Portex blue and the silicone rubber, wire-reinforced ET tubes. All tapes showed very poor or negligible adhesion to the Sheridan and Portex reinforced ET tubes. Adhesion to these tubes was greatly improved by wrapping them tightly with an "op site" dressing prior to applying tape.
"Hot-wire" microfluidic flowmeter based on a microfiber coupler.
Yan, Shao-Cheng; Liu, Zeng-Yong; Li, Cheng; Ge, Shi-Jun; Xu, Fei; Lu, Yan-Qing
2016-12-15
Using an optical microfiber coupler (MC), we present a microfluidic platform for strong direct or indirect light-liquid interaction by wrapping a MC around a functionalized capillary. The light propagating in the MC and the liquid flowing in the capillary can be combined and divorced smoothly, keeping a long-distance interaction without the conflict of input and output coupling. Using this approach, we experimentally demonstrate a "hot-wire" microfluidic flowmeter based on a gold-integrated helical MC device. The microfluid inside the glass channel takes away the heat, then cools the MC and shifts the resonant wavelength. Due to the long-distance interaction and high temperature sensitivity, the proposed microfluidic flowmeter shows an ultrahigh flow rate sensitivity of 2.183 nm/(μl/s) at a flow rate of 1 μl/s. The minimum detectable change of the flow rate is around 9 nl/s at 1 μl/s.
First Results from the DUNE 35-ton Prototype using Cosmics
NASA Astrophysics Data System (ADS)
Insler, Jonathan; DUNE Collaboration
2016-03-01
The 35-ton prototype for the Deep Underground Neutrino Experiment (DUNE) Far Detector is a single-phase liquid argon time projection chamber (LAr-TPC) integrated detector that will take cosmics data for a two month run beginning in February 2016. The 35-ton prototype will characterize DUNE's Far Detector technology performance and provide a sample of real data for DUNE reconstruction algorithms. The 35-ton prototype has two drift volumes of lengths 2.23 m and 0.23 m on either side of its anode plane assembly (APA) and makes use of wire planes with wrapped wires and a photon detection system (PDS) utilizing photon detection panels read out by silicon photomultipliers (SiPMs). Data from the 35-ton LAr detector are expected to provide rich information on scintillation light and charged particle tracks. We present a preliminary analysis of cosmics data taken with the 35-ton detector with a focus on stopping muons.
Vibrations of beams and rods carrying a moving mass
NASA Astrophysics Data System (ADS)
Zhao, X. W.; van der Heijden, G. H. M.; Hu, Z. D.
2016-05-01
We study the vibration of slender one-dimensional elastic structures (beams, cables, wires, rods) under the effect of a moving mass or load. We first consider the classical small- deflection (Euler-Bernoulli) beam case, where we look at tip vibrations of a cantilever as a model for a barreled launch system. Then we develop a theory for large deformations based on Cosserat rod theory. We illustrate the effect of moving loads on large-deformation structures with a few cable and arch problems. Large deformations are found to have a resonance detuning effect on the cable. For the arch we find different failure modes depending on its depth: a shallow arch fails by in-plane collapse, while a deep arch fails by sideways flopping. In both cases the speed of the traversing load is found to have a stabilising effect on the structure, with failure suppressed entirely at sufficiently high speed.
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For the first time, we report density-assisted self-assembly and efficient synthesis of gold (Au) and platinum (Pt) nanospheres, nanowires and nanorods using vitamin B2 (riboflavin) without employing any special capping or dispersing agent at room temperature; this env...
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Probing Active Nematic Films with Magnetically Manipulated Colloids
NASA Astrophysics Data System (ADS)
Rivas, David; Chen, Kui; Henry, Robert; Reich, Daniel; Leheny, Robert
We study microtubule-based extensile active nematic films using rod-like and disk-shaped magnetic colloids to probe the mechanical and hydrodynamic properties of this quasi-two dimensional out-of-equilibrium system. The active nematics are driven by molecular motors that hydrolyze ATP and cause sliding motion between microtubular bundles. This motion produces a dynamic nematic director field, which continuously creates pairs of +1/2 and -1/2 defects. In the absence of externally applied forces or torques, we observe that the magnetic rods in contact with the films align with the local director, indicating the existence of mechanical coupling between the film and probe. By applying known magnetic torques to the rods and observing their rotation with respect to the director, we gain insight into this coupling. We also find that by rotating magnetic microdisks using magnetic fields, hydrodynamic flows are produced that compete with the films' intrinsic flow, leading to significant effects on the director field and the defect landscape. At certain rotation rates, the disks produce a vortex-like structure in the director field and cause the creation and shedding of defects from the disk boundary.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Swulius, Matthew T.; Chen, Songye; Jane Ding, H.
2011-04-22
Highlights: {yields} No long helical filaments are seen near or along rod-shaped bacterial inner membranes by electron cryo-tomography. {yields} Electron cryo-tomography has the resolution to detect single filaments in vivo. -- Abstract: How rod-shaped bacteria form and maintain their shape is an important question in bacterial cell biology. Results from fluorescent light microscopy have led many to believe that the actin homolog MreB and a number of other proteins form long helical filaments along the inner membrane of the cell. Here we show using electron cryotomography of six different rod-shaped bacterial species, at macromolecular resolution, that no long (>80 nm)more » helical filaments exist near or along either surface of the inner membrane. We also use correlated cryo-fluorescent light microscopy (cryo-fLM) and electron cryo-tomography (ECT) to identify cytoplasmic bundles of MreB, showing that MreB filaments are detectable by ECT. In light of these results, the structure and function of MreB must be reconsidered: instead of acting as a large, rigid scaffold that localizes cell-wall synthetic machinery, moving MreB complexes may apply tension to growing peptidoglycan strands to ensure their orderly, linear insertion.« less
NASA Astrophysics Data System (ADS)
Teng, Zhaojie; Zhang, Wenyan; Chen, Yiran; Pan, Hongmiao; Xiao, Tian; Wu, Long-Fei
2017-08-01
Magnetotactic bacteria are a group of Gram-negative bacteria that synthesize magnetic crystals, enabling them to navigate in relation to magnetic field lines. Morphologies of magnetotactic bacteria include spirillum, coccoid, rod, vibrio, and multicellular morphotypes. The coccid shape is generally the most abundant morphotype among magnetotactic bacteria. Here we describe a species of giant rod-shaped magnetotactic bacteria (designated QR-1) collected from sediment in the low tide zone of Huiquan Bay (Yellow Sea, China). This morphotype accounted for 90% of the magnetotactic bacteria collected, and the only taxonomic group which was detected in the sampling site. Microscopy analysis revealed that QR-1 cells averaged (6.71±1.03)×(1.54±0.20) μm in size, and contained in each cell 42-146 magnetosomes that are arranged in a bundle formed one to four chains along the long axis of the cell. The QR-1 cells displayed axial magnetotaxis with an average velocity of 70±28 μm/s. Transmission electron microscopy based analysis showed that QR-1 cells had two tufts of flagella at each end. Phylogenetic analysis of the 16S rRNA genes revealed that QR-1 together with three other rod-shaped uncultivated magnetotactic bacteria are clustered into a deep branch of Alphaproteobacteria.
Bogie, Rob; Voss, Laura; Arts, Jacobus J; Lataster, Arno; Willems, Paul C; Brans, Boudewijn; van Rhijn, Lodewijk W; Welting, Tim J M
2016-12-01
An animal study. To explore ultra-high molecular weight polyethylene (UHMWPE) sublaminar wires in spinal surgery and to assess stability and biocompatibility of the UHMWPE instrumentation in an ovine model. Sublaminar wiring is a well-established technique in segmental scoliosis surgery. However, during introduction and/or removal of the metal sublaminar wires, neurological problems can occur. Abrasion after cutting metal wires for removal can lead to damage to the dural sac. Sublaminar wires have to withhold large forces and breakage of the wires can occur. Different types of sublaminar wires have been developed to address these problems. UHMWPE sublaminar wires can potentially substitute currently used metal sublaminar metal wires. In vivo testing and biocompatibility analysis of UHMWPE wires are recommended before clinical use in spinal surgery. In 6 immature sheep, pedicle screws were instrumented at lumbar level L4 and attached with titanium rods to 4 thoracolumbar vertebrae using 3- and 5-mm-wide UHMWPE sublaminar wiring constructions in 5 animals. Titanium sublaminar wires were applied in 1 animal to function as a control subject. After a follow-up period of 16 weeks, the animals were sacrificed and the spines were isolated. Radiographs and computed tomography (CT) scans were made to assess stability of the instrumentation. The vertebrae were dissected for macroscopic and histologic evaluation. None of the wires had loosened and the instrumentation remained stable. CT scans and radiographs showed no signs of failure of the instrumentation and no neurological complications occurred. Although several bony bridges were seen on CT, growth was observed at the operated levels. Biocompatibility was assessed by macroscopical and histologic analysis, showing no signs of dural or epidural inflammation. This pilot animal study shows that UHMWPE sublaminar wiring is a safe technique. The UHMWPE wires are biocompatible and provide sufficient stability in spinal instrumentation. Heterotopic ossification because of periost reactions in the ovine spine led to some restrictions in this study.
Simulation studies of self-organization of microtubules and molecular motors.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jian, Z.; Karpeev, D.; Aranson, I. S.
We perform Monte Carlo type simulation studies of self-organization of microtubules interacting with molecular motors. We model microtubules as stiff polar rods of equal length exhibiting anisotropic diffusion in the plane. The molecular motors are implicitly introduced by specifying certain probabilistic collision rules resulting in realignment of the rods. This approximation of the complicated microtubule-motor interaction by a simple instant collision allows us to bypass the 'computational bottlenecks' associated with the details of the diffusion and the dynamics of motors and the reorientation of microtubules. Consequently, we are able to perform simulations of large ensembles of microtubules and motors onmore » a very large time scale. This simple model reproduces all important phenomenology observed in in vitro experiments: Formation of vortices for low motor density and raylike asters and bundles for higher motor density.« less
The Formation of Fibrils by Intertwining of Filaments: Model and Application to Amyloid Aβ Protein
van Gestel, Jeroen; de Leeuw, Simon W.
2007-01-01
We outline a model that describes the interaction of rods that form intertwined bundles. In this simple model, we compare the elastic energy penalty that arises due to the deformation of the rods to the gain in binding energy upon intertwining. We find that, for proper values of the bending Young's modulus and the binding energy, a helical pitch may be found for which the energy of intertwining is most favorable. We apply our description to the problem of Alzheimer's Aβ protein fibrillization. If we forbid configurations that exhibit steric overlap between the protofilaments that make up a protein fibril, our model predicts that fibrils consisting of three protofilaments shall form. This agrees well with experimental results. Our model can also provide an estimate for the helical pitch of suitable fibrils. PMID:17114229
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bakosi, Jozsef; Christon, Mark A.; Francois, Marianne M.
This report describes the work carried out for completion of the Thermal Hydraulics Methods (THM) Level 3 Milestone THM.CFD.P5.05 for the Consortium for Advanced Simulation of Light Water Reactors (CASL). A series body-fitted computational meshes have been generated by Numeca's Hexpress/Hybrid, a.k.a. 'Spider', meshing technology for the V5H 3x3 and 5x5 rod bundle geometry used to compute the fluid dynamics of grid-to-rod fretting (GTRF). Spider is easy to use, fast, and automatically generates high-quality meshes for extremely complex geometries, required for the GTRF problem. Hydra-TH has been used to carry out large-eddy simulations on both 3x3 and 5x5 geometries, usingmore » different mesh resolutions. The results analyzed show good agreement with Star-CCM+ simulations and experimental data.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bakosi, Jozsef; Christon, Mark A.; Francois, Marianne M.
This report describes the work carried out for completion of the Thermal Hydraulics Methods (THM) Level 3 Milestone THM.CFD.P5.05 for the Consortium for Advanced Simulation of Light Water Reactors (CASL). A series of body-fitted computational meshes have been generated by Numeca's Hexpress/Hybrid, a.k.a. 'Spider', meshing technology for the V5H 3 x 3 and 5 x 5 rod bundle geometries and subsequently used to compute the fluid dynamics of grid-to-rod fretting (GTRF). Spider is easy to use, fast, and automatically generates high-quality meshes for extremely complex geometries, required for the GTRF problem. Hydra-TH has been used to carry out large-eddy simulationsmore » on both 3 x 3 and 5 x 5 geometries, using different mesh resolutions. The results analyzed show good agreement with Star-CCM+ simulations and experimental data.« less
Lord, David E.; Carter, Gary W.; Petrini, Richard R.
1983-01-01
A video flowmeter is described that is capable of specifying flow nature and pattern and, at the same time, the quantitative value of the rate of volumetric flow. An image of a determinable volumetric region within a fluid (10) containing entrained particles (12) is formed and positioned by a rod optic lens assembly (31) on the raster area of a low-light level television camera (20). The particles (12) are illuminated by light transmitted through a bundle of glass fibers (32) surrounding the rod optic lens assembly (31). Only particle images having speeds on the raster area below the raster line scanning speed may be used to form a video picture which is displayed on a video screen (40). The flowmeter is calibrated so that the locus of positions of origin of the video picture gives a determination of the volumetric flow rate of the fluid (10).
NASA Astrophysics Data System (ADS)
Fukayama, Osamu; Taniguchi, Noriyuki; Suzuki, Takafumi; Mabuchi, Kunihiko
We are developing a brain-machine interface (BMI) called “RatCar," a small vehicle controlled by the neural signals of a rat's brain. An unconfined adult rat with a set of bundled neural electrodes in the brain rides on the vehicle. Each bundle consists of four tungsten wires isolated with parylene polymer. These bundles were implanted in the primary motor and premotor cortices in both hemispheres of the brain. In this paper, methods and results for estimating locomotion speed and directional changes are described. Neural signals were recorded as the rat moved in a straight line and as it changed direction in a curve. Spike-like waveforms were then detected and classified into several clusters to calculate a firing rate for each neuron. The actual locomotion velocity and directional changes of the rat were recorded concurrently. Finally, the locomotion states were correlated with the neural firing rates using a simple linear model. As a result, the abstract estimation of the locomotion velocity and directional changes were achieved.
NASA Astrophysics Data System (ADS)
Javed, Mohsin; Abbas, Syed Mustansar; Siddiq, Mohammad; Han, Dongxue; Niu, Li
2018-02-01
A high charge-carrier transport is an important aim in the synthesis of nanostructures for an effective supercapacitor. This article describes a methodology to prepare mesoporous silica nanoparticles (MSNs) wrapped with graphene oxide (GO) together with conducting polyaniline (PANI) wires. The morphology and chemical structure of the prepared samples have been tested by transmission electron microscopy (TEM), high-resolution TEM (HRTEM), and X-ray diffraction (XRD), whereas the stability and electrostatic interaction of the structures have been verified by thermogravimetric analysis (TGA) and Fourier-transform infrared (FT-IR) spectroscopy, respectively. The supercapacitive behaviour of these nanocomposites has been analysed by cyclic voltammetry (CV), charge-discharge tests, and electrochemical impedance spectroscopy (EIS). Compared with pristine MSNs and PANI, the 20%-GO@MSNs/PANI nanocomposite had the highest specific capacitance, reaching 412 F g-1. The nanocomposite structure maximizes the synergy between mesoporous metal oxide, conducting PANI, and GO, yielding a significantly enhanced specific capacitance, rapid charge-discharge rates, and good cycling stability of the resulting device. The wrapping with GO prevents the structural breakdown and acts as a highly conductive pathway by bridging the individual particles, whereas the MSNs nanoparticles greatly enlarge the specific surface area to facilitate ion transport and charge transfer throughout the cycling performance of supercapacitor. The approach adopted in this article can be applied for preparing similar novel functional materials in future for electrochemical applications.
Bone response to a titanium aluminium nitride coating on metallic implants.
Freeman, C O; Brook, I M
2006-05-01
The design, surface characteristics and strength of metallic implants are dependant on their intended use and clinical application. Surface modifications of materials may enable reduction of the time taken for osseointegration and improve the biological response of bio-mechanically favourable metals and alloys. The influence of a titanium aluminium nitride (TAN) coating on the response of bone to commercially pure titanium and austenitic 18/8 stainless steel wire is reported. TAN coated and plain rods of stainless steel and commercially pure titanium were implanted into the mid-shaft of the femur of Wistar rats. The femurs were harvested at four weeks and processed for scanning electron and light microscopy. All implants exhibited a favourable response in bone with no evidence of fibrous encapsulation. There was no significant difference in the amount of new bone formed around the different rods (osseoconduction), however, there was a greater degree of shrinkage separation of bone from the coated rods than from the plain rods (p = 0.017 stainless steel and p = 0.0085 titanium). TAN coating may result in reduced osseointegration between bone and implant.
A NEW PRINCIPLE FOR ELECTROMAGNETIC CATHETER FLOW METERS*
Kolin, Alexander
1969-01-01
An electromagnetic catheter flow meter is described in which the magnetic field is generated by two parallel bundles of wire carrying equal currents in opposite directions. The electrodes are fixed centrally to the insulated wire bundles that generate the magnetic field. The flow sensor is flexible, resembling a split catheter. The flow transducer is designed to constrict as it is introduced through a branch artery and to expand in the main artery over the span of its diameter. The principle is suitable for branch flow measurement as well as for measurement of flow in a major artery or vein by the same transducer. A special method of guiding the electrode wires results in a zero base line at zero flow for the entire range of diameters accommodating the field generating coil. The electrodes could be used in this configuration with a magnetic field generated by coils external to the patient for blood flow measurements with a catheter of reduced gauge. The transducer can be made smaller in circumference than those employed in other electromagnetic flow measuring catheter devices. This feature is of special value for envisaged clinical uses (percutaneous introduction) to minimize surgical intervention. The velocity sensitivity of the flow transducer is a logarithmic function of the tube diameter. The flow throughout the entire tube cross section contributes to the flow signal. It is sufficient to calibrate the transducer by one measurement in a dielectric conduit of less than maximum diameter. The sensitivity at other diameters follows from a logarithmic plot. The diameter of the blood vessel is outlined by the transducer in radiograms, thus obviating the need for radiopaque materials. The principle was demonstrated by measurements in vitro. Experiments in vivo, derivation of equations, and construction details will be published elsewhere. Images PMID:5257127
Pulling helices inside bacteria: imperfect helices and rings
NASA Astrophysics Data System (ADS)
Rutenberg, Andrew; Allard, Jun
2009-03-01
We study steady-state configurations of intrinsically-straight elastic filaments constrained within rod-shaped bacteria that have applied forces distributed along their length. Perfect steady-state helices result from axial or azimuthal forces applied at filament ends, however azimuthal forces are required for the small pitches observed for MreB filaments within bacteria. Helix-like configurations can result from distributed forces, including co-existence between rings and imperfect helices. Levels of expression and/or bundling of the polymeric protein could mediate this co-existence.
Pulling Helices inside Bacteria: Imperfect Helices and Rings
NASA Astrophysics Data System (ADS)
Allard, Jun F.; Rutenberg, Andrew D.
2009-04-01
We study steady-state configurations of intrinsically-straight elastic filaments constrained within rod-shaped bacteria that have applied forces distributed along their length. Perfect steady-state helices result from axial or azimuthal forces applied at filament ends, however azimuthal forces are required for the small pitches observed for MreB filaments within bacteria. Helix-like configurations can result from distributed forces, including coexistence between rings and imperfect helices. Levels of expression and/or bundling of the polymeric protein could mediate this coexistence.
Page, A M; Lagnado, J R
2000-10-01
Phytomonas sp. derived from Euphorbia pinea are digenetic plant trypanosomes that are transmitted by the squashbug Stenocephalus agilis and exist exclusively as promastigotes. The stable sub-pellicular microtubular array, the flagellar axoneme and the paraflagellar rod represent the major cytoskeletal components common to all trypanosomes. The work described in this paper examines in detail the ultrastructural morphology of the organism and highlights a number of novel structural features, and in particular, the presence of some detergent-resistant proteins which take the form of bundles of trans-cytoplasmic filaments of ca. 10 nm in diameter, seen in cells from both log- and stationary-phase cultures. The ultrastructural morphology and immunological cross-reactivity of these filaments are described, and their relationship to filamentous bundles previously reported in stationary-phase cultures of Crithidia fasciculata and to intermediate filaments of animal cells is discussed.
Analytical methods in the high conversion reactor core design
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zeggel, W.; Oldekop, W.; Axmann, J.K.
High conversion reactor (HCR) design methods have been used at the Technical University of Braunschweig (TUBS) with the technological support of Kraftwerk Union (KWU). The present state and objectives of this cooperation between KWU and TUBS in the field of HCRs have been described using existing design models and current activities aimed at further development and validation of the codes. The hard physical and thermal-hydraulic boundary conditions of pressurized water reactor (PWR) cores with a high degree of fuel utilization result from the tight packing of the HCR fuel rods and the high fissionable plutonium content of the fuel. Inmore » terms of design, the problem will be solved with rod bundles whose fuel rods are adjusted by helical spacers to the proposed small rod pitches. These HCR properties require novel computational models for neutron physics, thermal hydraulics, and fuel rod design. By means of a survey of the codes, the analytical procedure for present-day HCR core design is presented. The design programs are currently under intensive development, as design tools with a solid, scientific foundation and with essential parameters that are widely valid and are required for a promising optimization of the HCR core. Design results and a survey of future HCR development are given. In this connection, the reoptimization of the PWR core in the direction of an HCR is considered a fascinating scientific task, with respect to both economic and safety aspects.« less
Microbiological sampling of returned Surveyor 3 electrical cabling
NASA Technical Reports Server (NTRS)
Knittel, M. D.; Favero, M. S.; Green, R. H.
1972-01-01
A piece of electrical wiring bundle running from the television camera to another part of the spacecraft was selected for microbiological examination. Sampling methods are discussed. The results presented show that no viable microorganisms were recovered from the part of the Surveyor 3 cable which was tested. Factors that could have contributed to the sterility of the cable are thermal vacuum testing, natural dieoff, change in pressure during launch, and lunar vacuum and temperature.
Ye, Enyi; Zhang, Shuang-Yuan; Liu, Shuhua; Han, Ming-Yong
2011-03-07
The coating makes the wire bundle: High-quality free-standing copper nanowires have been successfully produced by disproportionation of Cu(+) in oleylamine. This provides an effective way to prepare high-quality copper nanowires, but also enriches synthetic routes to other nanostructures. These copper nanowires can self-assemble by surface ligand exchange of oleylamine with trioctylphosphine. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Methodology for the study of the boiling crisis in a nuclear fuel bundle
DOE Office of Scientific and Technical Information (OSTI.GOV)
Crecy, F. de; Juhel, D.
1995-09-01
The boiling crisis is one of the phenoumena limiting the available power from a nuclear power plant. It has been widely studied for decades, and numerous data, models, correlations or tables are now available in the literature. If we now try to obtain a general view of previous work in this field, we may note that there are several ways of tackling the subject. The mechanistic models try to model the two-phase flow topology and the interaction between different sublayers, and must be validated by comparison with basic experiments, such as DEBORA, where we try to obtain some detailed informationsmore » on the two-phase flow pattern in a pure and simple geometry. This allows us to obtain better knowledge of the so-called {open_quotes}intrinsic effect{close_quotes}. These models are not yet acceptable for nuclear use. As the geometry of the rod bundles and grids has a tremendous importance for the Critical Heat Flux (CHF), it is mandatory to have more precise results for a given fuel rod bundle in a restricted range of parameters: this leads to the empirical approach, using empirical CHF predictors (tables, correlations, splines, etc...). One of the key points of such a method is the obtaining local thermohydraulic values, that is to say the evaluation of the so-called {open_quotes}mixing effect{close_quotes}. This is done by a subchannel analysis code or equivalent, which can be qualified on two kinds of experiments: overall flow measurements in a subchannel, such as HYDROMEL in single-phase flow or GRAZIELLA in two-phase flow, or detailed measurements inside a subchannel, such as AGATE. Nevertheless, the final qualification of a specific nuclear fuel, i.e. the synthesis of these mechanistic and empirical approaches, intrinsic and mixing effects, etc..., must be achieved on a global test such as OMEGA. This is the strategy used in France by CEA and its partners FRAMATOME and EdF.« less
NASA Astrophysics Data System (ADS)
Abir, Ahmed Musafi
Spacer grids are used in Pressurized Water Reactors (PWRs) fuel assemblies which enhances heat transfer from fuel rods. However, there remain regions of low turbulence in between the spacer grids. To enhance turbulence in these regions surface roughness is applied on the fuel rod walls. Meyer [1] used empirical correlations to predict heat transfer and friction factor for artificially roughened fuel rod bundles at High Performance Light Water Reactors (LWRs). Their applicability was tested by Carrilho at University of South Carolina's (USC) Single Heated Element Loop Tester (SHELT). He attained a heat transfer and friction factor enhancement of 50% and 45% respectively, using Inconel nuclear fuel rods with square transverse ribbed surface. Following him Najeeb conducted a similar study due to three dimensional diamond shaped blocks in turbulent flow. He recorded a maximum heat transfer enhancement of 83%. At present, several types of materials are being used for fuel rod cladding including Zircaloy, Uranium oxide, etc. But researchers are actively searching for new material that can be a more practical alternative. Silicon Carbide (SiC) has been identified as a material of interest for application as fuel rod cladding [2]. The current study deals with the experimental investigation to find out the friction factor increase of a SiC fuel rod with 3D surface roughness. The SiC rod was tested at USC's SHELT loop. The experiment was conducted in turbulent flowing Deionized (DI) water at steady state conditions. Measurements of Flow rate and pressure drop were made. The experimental results were also validated by Computational Fluid Dynamics (CFD) analysis in ANSYS Fluent. To simplify the CFD analysis and to save computational resources the 3D roughness was approximated as a 2D one. The friction factor results of the CFD investigation was found to lie within +/-8% of the experimental results. A CFD model was also run with the energy equation turned on, and a heat generation of 8 kW applied to the rod. A maximum heat transfer enhancement of 18.4% was achieved at the highest flow rate investigated (i.e. Re=109204).
Kim, Hee Jin; Lee, Tae Won; Ihm, Chun Gyoo; Kim, Myung Jae
2002-01-01
Peritoneal catheter is the lifeline for the continuous ambulatory peritoneal dialysis (CAPD) patients. Over the years, obstruction or displacement of the CAPD catheter has been one of the common complications of CAPD. Fluoroscopy-guided wire manipulation or laparoscopic surgery has been developed to manage outflow obstruction. We analyzed the catheter outcome of fluoroscopy-guided wire manipulation or laparoscopic surgery to determine the ultimate benefit of these procedures. From June 1996 to August 2000, catheter complications were manipulated in 24 patients. Eleven (46%) of these patients were initially managed by guide wire under fluoroscopic control. The remaining 13 (54%) patients were manipulated by laparoscopic surgery. A successful outcome was defined as maintained normal peritoneal catheter function at 30 days after the manipulations. Among the catheters manipulated, 18 (75%) were inserted by nephrologist and 6 (25%) by surgeons at the initiation of CAPD. Tenckhoff double-cuff peritoneal catheters were inserted to all patients. The time elapsed between catheter insertion and manipulation varied from 1 to 60 days with a mean of 11 days. The primary causes of catheter malfunction were kinking in 1 case, omental wrapping with adhesions in 9 cases, and catheter displacements in the remaining 14 cases. Thirty-day catheter function was achieved in 50% (12/24) of initial catheter manipulations, with guide wire under fluoroscopic control (46%, 5/11) and laparoscopic surgery (54%, 7/13). Overall success rate of repeated manipulation was 71% (17 of 24). The successful outcome in repairing of the malfunctioning CAPD catheters could be increased by the combination of fluoroscopy-guided wire manipulation and laparoscopic surgery. Copyright 2002 S. Karger AG, Basel
Choi, Eunsoo; Kim, Dongkyun; Park, Kyoungsoo
2014-12-01
For external jackets of reinforced concrete columns, shape memory alloy (SMA) wires are easy to install, and they provide active and passive confining pressure; steel plates, on the other hand, only provide passive confining pressure, and their installation on concrete is not convenient because of the requirement of a special device. To investigate how SMA wires distinctly impact bond behavior compared with steel plates, this study conducted push-out bond tests of steel reinforcing bars embedded in concrete confined by SMA wires or steel plates. For this purpose, concrete cylinders were prepared with dimensions of 100 mm x 200 mm, and D-22 reinforcing bars were embedded at the center of the concrete cylinders. External jackets of 1.0 mm and 1.5 mm thickness steel plates were used to wrap the concrete cylinders. Additionally, NiTiNb SMA wire with a diameter of 1.0 mm was wound around the concrete cylinders. Slip of the reinforcing bars due to pushing force was measured by using a displacement transducer, while the circumferential deformation of specimens was obtained by using an extensometer. The circumferential deformation was used to calculate the circumferential strains of the specimens. This study assessed the radial confining pressure due to the external jackets on the reinforcing bars at bond strength from bond stress-slip curves and bond stress-circumferential strain curves. Then, the effects of the radial confining pressure on the bond behavior of concrete are investigated, and an equation is suggested to estimate bond strength using the radial confining pressure. Finally, this study focused on how active confining pressure due to recovery stress of the SMA wires influences bond behavior.
Federal Register 2010, 2011, 2012, 2013, 2014
2013-09-13
... choose the duty rate during customs entry procedures that applies to fuel rod assemblies (duty rate--3.3... plates; channels; spacers; end caps; springs; top and bottom nozzles; cages; guide tubes; and tubes, bar stocks, wires and plates of zirconium (duty rate ranges from 3.3 to 3.7%). Public comment is invited from...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Daniels, W.J.; Donohue, M.T.; Singal, M.
Environmental and brathing zone samples were analyzed for di(2-ethylhexyl)adipate, hydrogen-chloride, cyclohexanol, dicyclohexyl-phthalate, phthalic-anhydride, and total particulates at Ashland Super Valu, Ashland, Wisconsin in June, 1984. The evaluation was requested by a company representative due to complaints of respiratory problems by one of the meat department employees. Four meat department employees were interviewed. The authors conclude that it is not possible to determine whether or not the symptoms reported by the meat packer are due to emissions from heated meat wrap or label adhesive. Recommendations included not operating the cool rod cutter at a temperature above 280 degrees-F and installing localmore » exhaust ventilation.« less
GaAs laser diode pumped Nd:YAG laser
NASA Technical Reports Server (NTRS)
Conant, L. C.; Reno, C. W.
1974-01-01
A 1.5-mm by 3-cm neodymium-ion doped YAG laser rod has been side pumped using a GaAs laser diode array tuned to the 8680-A absorption line, achieving a multimode average output power of 120 mW for a total input power of 20 W to the final-stage laser diode drivers. The pumped arrangement was designed to take advantage of the high brightness of a conventional GaAs array as a linear source by introducing the pump light through a slit into a close-wrapped gold coated pump cavity. This cavity forms an integrating chamber for the pump light.
Powder-metallurgical preparation of A15 superconductors
NASA Astrophysics Data System (ADS)
Wilhelm, Manfred; Wohlleben, Karl; Springer, Engelbert; Mrowiec, Klaus; Schaper, Wilfried; Wecker, Joachim
1985-08-01
The powder-metallurgical preparation of Cu-Nb3Sn microcomposite superconductors was investigated in order to economize in the manufacture of the conductors and to improve their mechanical and electrical properties. Conditions during high temperature extrusion are optimized by adding Al or Ti as reducing agents, also with a view to the following cold forming. Current densities well above 10,000 A/sq cm at 15T are obtained by applying coarse-grained Nb powder and incorporating small quantities of Ta or Ti. The current carrying behavior of the conductors was determined as a function of the degree of mechanical deformation, the cold forming technique, and the heat treatment conditions. Wires containing an internal tin source as well as bundled assemblies for high current applications were manufactured. Long wires can be produced.
Square-lashing technique in segmental spinal instrumentation: a biomechanical study.
Arlet, Vincent; Draxinger, Kevin; Beckman, Lorne; Steffen, Thomas
2006-07-01
Sublaminar wires have been used for many years for segmental spinal instrumentation in scoliosis surgery. More recently, stainless steel wires have been replaced by titanium cables. However, in rigid scoliotic curves, sublaminar wires or simple cables can either brake or pull out. The square-lashing technique was devised to avoid complications such as cable breakage or lamina cutout. The purpose of the study was therefore to test biomechanically the pull out and failure mode of simple sublaminar constructs versus the square-lashing technique. Individual vertebrae were subjected to pullout testing having one of two different constructs (single loop and square lashing) using either monofilament wire or multifilament cables. Four different methods of fixation were therefore tested: single wire construct, square-lashing wiring construct, single cable construct, and square-lashing cable construct. Ultimate failure load and failure mechanism were recorded. For the single wire the construct failed 12/16 times by wire breakage with an average ultimate failure load of 793 N. For the square-lashing wire the construct failed with pedicle fracture in 14/16, one bilateral lamina fracture, and one wire breakage. Ultimate failure load average was 1,239 N For the single cable the construct failed 12/16 times due to cable breakage (average force 1,162 N). 10/12 of these breakages were where the cable looped over the rod. For the square-lashing cable all of these constructs (16/16) failed by fracture of the pedicle with an average ultimate failure load of 1,388 N. The square-lashing construct had a higher pullout strength than the single loop and almost no cutting out from the lamina. The square-lashing technique with cables may therefore represent a new advance in segmental spinal instrumentation.
Electric Motor Thermal Management Research: Annual Progress Report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bennion, Kevin S.
Past work in the area of active convective cooling provided data on the average convective heat transfer coefficients of circular orifice automatic transmission fluid (ATF) jets impinging on stationary targets intended to represent the wire bundle surface of the motor end-winding. Work during FY16 focused on the impact of alternative jet geometries that could lead to improved cooling over a larger surface of the motor winding. Results show that the planar jet heat transfer coefficients over a small (12.7-mm-diameter) target surface are not too much lower than for the circular orifice jet in which all of the ATF from themore » jet impinges on the target surface. The planar jet has the potential to achieve higher heat transfer over a larger area of the motor end winding. A new test apparatus was constructed to measure the spatial dependence of the heat transfer relative to the jet nozzle over a larger area representative of a motor end-winding. The tested planar flow geometry has the potential to provide more uniform cooling over the full end-winding surface versus the conventional jet configuration. The data will be used by motor designers to develop thermal management strategies to improve motor power density. Work on passive thermal design in collaboration with Oak Ridge National Laboratory to measure the thermal conductivity of wire bundle samples representative of end-winding and slot-winding materials was completed. Multiple measurement techniques were compared to determine which was most suitable for measuring composite wire bundle samples. NREL used a steady-state thermal resistance technique to measure the direction-dependent thermal conductivity. The work supported new interactions with industry to test new materials and reduce passive-stack thermal resistance in motors, leading to motors with increased power density. NREL collaborated with Ames Laboratory in the area of material characterization. The work focused on measuring the transverse rupture strength of new magnet materials developed at Ames. The impact of the improved transverse rupture strength is a mechanically stronger magnet that is easier for manufacturers to implement into motor designs. The thermal conductivity of the new magnet materials was also measured in comparison to two commercially available AlNiCo magnet materials. The impact of the thermal conductivity of the magnet material will need to be analyzed in the context of a motor application.« less
Anomalous water expulsion from carbon-based rods at high humidity
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nune, Satish K.; Lao, David B.; Heldebrant, David J.
Managing water is critical for industrial applications including CO2 capture, catalysis, bio-oil separations and energy storage. Various classes of materials have been designed for these applications, achieving specific water adsorption capacities at a given relative humidity (RH). Three water adsorption-desorption mechanisms are common to inorganic materials: (1) chemisorption, which may lead to the modification of the first coordination sphere; (2) simple adsorption, which is reversible in nature; or (3) capillary condensation, which is irreversible in nature. Regardless of sorption mechanism, all materials known today increase water adsorption capacity with increasing RH; none exhibit repeated adsorption of water at low humiditymore » and release at high humidity. We present here a material that breaks from this convention: a new class of nitrogen containing carbon rods along with nonstoichiometric FeXSY that adsorb water at low humidity, and spontaneously expel half of the adsorbed water when the RH exceeds a 50–80% threshold. Monolayers of water form on the surfaces of the carbon rods, with the amount of water adsorbed directly linked to the aspect ratio of the rods and the available surface area. This unprecedented water expulsion is a reversible physical process. Once a complete monolayer is formed, adjacent rods in the bundles begin to adhere together via formation of a bridging monolayer, reducing the surface area available for water to adhere to. We believe the unique surface chemistry of these carbon rods can be used on other functionalized materials. Such behaviour offers a paradigm shift in water purification and separation: water could be repeatedly adsorbed from a low humidity vapour stream and then expelled into a pure water vapour stream, or humidity-responsive membranes could change their water permeance or selectivity as a function of RH.« less
Stability test and analysis of the Space Shuttle Primary Reaction Control Subsystem thruster
NASA Technical Reports Server (NTRS)
Applewhite, John; Hurlbert, Eric; Krohn, Douglas; Arndt, Scott; Clark, Robert
1992-01-01
The results are reported of a test program conducted on the Space Shuttle Primary Reaction Control Subsystem thruster in order to investigate the effects of trapped helium bubbles and saturated propellants on stability, determine if thruster-to-thruster stability variations are significant, and determine stability under STS-representative conditions. It is concluded that the thruster design is highly reliable in flight and that burn-through has not occurred. Significantly unstable thrusters are screened out, and wire wrap is found to protect against chamber burn-throughs and to provide a fail-safe thruster for this situation.
NASA Astrophysics Data System (ADS)
Yoon, Min-Seok; Han, Young-Geun
2014-05-01
A highly sensitive current sensor based on an optical microfiber loop resonator (MLR) incorporating low index polymer is proposed and experimentally demonstrated. The microfiber with a waist diameter of 1 μm is wrapped around the nicrhrome wire with low index polymer coating and the optical MLR is realized. The use of the microfiber and low index polymer with high thermal property can effectively improve the current sensitivity of the proposed MLR-based sensing probe to be 437.9 pm/A2, which is ~10 times higher than the previous result.
Fabrication of liquid-rocket thrust chambers by electroforming
NASA Technical Reports Server (NTRS)
Duscha, R. A.; Kazaroff, J. M.
1974-01-01
Electroforming has proven to be an excellent fabrication method for building liquid rocket regeneratively cooled thrust chambers. NASA sponsored technology programs have investigated both common and advanced methods. Using common procedures, several cooled spool pieces and thrust chambers have been made and successfully tested. The designs were made possible through the versatility of the electroforming procedure, which is not limited to simple geometric shapes. An advanced method of electroforming was used to produce a wire-wrapped, composite, pressure-loaded electroformed structure, which greatly increased the strength of the structure while still retaining the advantages of electroforming.
NASA Technical Reports Server (NTRS)
Bohning, O. D.; Becker, F. J.
1980-01-01
Design, fabrication and test of partially populated prototype recorder using 100 kilobit serial chips is described. Electrical interface, operating modes, and mechanical design of several module configurations are discussed. Fabrication and test of the module demonstrated the practicality of multiplexing resulting in lower power, weight, and volume. This effort resulted in the completion of a module consisting of a fully engineered printed circuit storage board populated with 5 of 8 possible cells and a wire wrapped electronics board. Interface of the module is 16 bits parallel at a maximum of 1.33 megabits per second data rate on either of two interface buses.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ionescu-Bujor, Mihaela; Jin Xuezhou; Cacuci, Dan G.
2005-09-15
The adjoint sensitivity analysis procedure for augmented systems for application to the RELAP5/MOD3.2 code system is illustrated. Specifically, the adjoint sensitivity model corresponding to the heat structure models in RELAP5/MOD3.2 is derived and subsequently augmented to the two-fluid adjoint sensitivity model (ASM-REL/TF). The end product, called ASM-REL/TFH, comprises the complete adjoint sensitivity model for the coupled fluid dynamics/heat structure packages of the large-scale simulation code RELAP5/MOD3.2. The ASM-REL/TFH model is validated by computing sensitivities to the initial conditions for various time-dependent temperatures in the test bundle of the Quench-04 reactor safety experiment. This experiment simulates the reflooding with water ofmore » uncovered, degraded fuel rods, clad with material (Zircaloy-4) that has the same composition and size as that used in typical pressurized water reactors. The most important response for the Quench-04 experiment is the time evolution of the cladding temperature of heated fuel rods. The ASM-REL/TFH model is subsequently used to perform an illustrative sensitivity analysis of this and other time-dependent temperatures within the bundle. The results computed by using the augmented adjoint sensitivity system, ASM-REL/TFH, highlight the reliability, efficiency, and usefulness of the adjoint sensitivity analysis procedure for computing time-dependent sensitivities.« less
Barbero, David R; Stranks, Samuel D
2016-11-01
Carbon nanotubes have a variety of remarkable electronic and mechanical properties that, in principle, lend them to promising optoelectronic applications. However, the field has been plagued by heterogeneity in the distributions of synthesized tubes and uncontrolled bundling, both of which have prevented nanotubes from reaching their full potential. Here, a variety of recently demonstrated solution-processing avenues is presented, which may combat these challenges through manipulation of nanoscale structures. Recent advances in polymer-wrapping of single-walled carbon nanotubes (SWNTs) are shown, along with how the resulting nanostructures can selectively disperse tubes while also exploiting the favorable properties of the polymer, such as light-harvesting ability. New methods to controllably form nanoengineered SWNT networks with controlled nanotube placement are discussed. These nanoengineered networks decrease bundling, lower the percolation threshold, and enable a strong enhancement in charge conductivity compared to random networks, making them potentially attractive for optoelectronic applications. Finally, SWNT applications, to date, in organic and perovskite photovoltaics are reviewed, and insights as to how the aforementioned recent advancements can lead to improved device performance provided. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
NASA Astrophysics Data System (ADS)
Dandapat, Manika; Mandal, Debabrata
2017-01-01
Organogels prepared from AOT/4-chlorophenol/m-xylene are immobile in the macroscopic sense, with a well-characterized internal structure. However, the molecular level dynamics inside the gels is not too clear, although a very slow structural relaxation has been reported previously. Using a set of rod-like fluorophores, we find that the rotational mobility of a small guest molecule inside the gel can be extremely fast, indicating presence of sufficiently low-microviscosity domains. These domains consist of m-xylene solvent molecules trapped in the interstices of fiber bundles comprising columnar stacks of 4-chlorophenol surrounded by AOT molecules. However, interstitial trapping of m-xylene does retard its own dynamics, which explains the slow solvent relaxation inside the gels. Hence, the state of m-xylene in the organogel may be characterized as "bound", in contrast to the "free" state in neat m-xylene.
New types of time domain reflectometry sensing waveguides for bridge scour monitoring
NASA Astrophysics Data System (ADS)
Lin, Chih-Ping; Wang, Kai; Chung, Chih-Chung; Weng, Yu-Wen
2017-07-01
Scour is a major threat to bridge safety, especially in harsh fluvial environments. Real-time monitoring of bridge scour is still very limited due to the lack of robust and economic scour monitoring device. Time domain reflectometry (TDR) is an emerging waveguide-based technique holding great promise to develop more durable scour monitoring devices. This study presents new types of TDR sensing waveguides in forms of either sensing rod or sensing wire, taking into account of the measurement range, durability, and ease of field installation. The sensing rod is composed of a hollow grooved steel rod paired up with a metal strip on the insulating groove, while the sensing wire consists of two steel strands with one of them coated with an insulating jacket. The measurement sensitivity is inevitably sacrificed when other properties such as the measurement range, field durability, and installation easiness are enhanced. Factors affecting the measurement sensitivity were identified and experimentally evaluated for better arranging the waveguide conductors. A data reduction method for scour-depth estimation without the need for identifying the sediment/water reflection and a two-step calibration procedure for rating propagation velocities were proposed to work with the new types of TDR sensing waveguides. Both the calibration procedure and the data reduction method were experimentally validated. The test results indicated that the new TDR sensing waveguide provides accurate scour depth measurements regardless of the sacrificed sensitivity. The insulating coating of the new TDR sensing waveguide was also demonstrated to be effective in extending the measurement range up to at least 15 m.
Use of laparoscopy in the management of malfunctioning peritoneal dialysis catheters.
Brandt, C P; Ricanati, E S
1996-01-01
The proper function of peritoneal dialysis (PD) catheters can be compromised by catheter malposition, fibrin clot, or omental wrapping. The purpose of this study was to determine the efficacy of laparoscopy in the treatment of malfunctioning PD catheters. All patients undergoing laparoscopy for catheter dysfunction at MetroHealth Medical Center in Cleveland, Ohio, from 1991 to 1995, were reviewed. Twenty-six laparoscopies were performed in 22 patients, for malfunction occurring an average of 3.9 months following insertion (range 0.5-18 months). Omental and/or small below wrapping as present in all but three cases. Lysis of adhesions was required in 19 of 26 cases, with repositioning only in seven. Eight patients had failed attempts at stiff wire manipulation prior to laparoscopy. Perioperative complications occurred in seven cases, consisting of temporary dialysate leakage (2), enterotomy (1), and early reocclusion (4). Repeat laparoscopy was successful in three of these four reocclusions. The overall success rate (catheter function > 30 days after laparoscopy) was 21/22 (96%). Laparoscopy is highly accurate and effective in the management of peritoneal dialysis catheter dysfunction and results in prolongation of catheter life.
Technology That's Ready and Able to Inspect Those Cables
NASA Technical Reports Server (NTRS)
2005-01-01
Attempting to locate a malfunctioning wire in a complex bundle of wires or in a cable that is concealed behind a wall is as difficult as trying to find a needle in a haystack. The result of such an effort can also be costly, time-consuming, and frustrating, whether it is the tedious process of examining cable connections for the Space Shuttle or troubleshooting a cable television hookup. Furthermore, other maintenance restrictions can compound the effort required to locate and repair a particular wiring problem. For example, on the Space Shuttle, once a repair is completed, all systems that have a wire passing through any of the connectors that were disconnected during troubleshooting are affected and, therefore, must undergo retesting, an arduous task that is completely unrelated to the original problem. In an effort to streamline wire inspection and maintenance, two contractors supporting NASA's Kennedy Space Center invented the Standing Wave Reflectometer (SWR) in 1999. In doing so, they leveraged technology that was first developed to detect problems that could lead to aircraft accidents, such as the one that resulted in the catastrophic failure of TWA flight 800 in 1996. The SWR performs a non-intrusive inspection that verifies the condition of electrical power and signal-distribution systems inside the Space Shuttle orbiters. Such testing reduces processing delays and ensures safe operation of these systems.
Development of a HTSMA-Actuated Surge Control Rod for High-Temperature Turbomachinery Applications
NASA Technical Reports Server (NTRS)
Padula, Santo, II; Noebe, Ronald; Bigelow, Glen; Culley, Dennis; Stevens, Mark; Penney, Nicholas; Gaydosh, Darrell; Quackenbush, Todd; Carpenter, Bernie
2007-01-01
In recent years, a demand for compact, lightweight, solid-state actuation systems has emerged, driven in part by the needs of the aeronautics industry. However, most actuation systems used in turbomachinery require not only elevated temperature but high-force capability. As a result, shape memory alloy (SMA) based systems have worked their way to the forefront of a short list of viable options to meet such a technological challenge. Most of the effort centered on shape memory systems to date has involved binary NiTi alloys but the working temperatures required in many aeronautics applications dictate significantly higher transformation temperatures than the binary systems can provide. Hence, a high temperature shape memory alloy (HTSMA) based on NiTiPdPt, having a transformation temperature near 300 C, was developed. Various thermo-mechanical processing schemes were utilized to further improve the dimensional stability of the alloy and it was later extruded/drawn into wire form to be more compatible with envisioned applications. Mechanical testing on the finished wire form showed reasonable work output capability with excellent dimensional stability. Subsequently, the wire form of the alloy was incorporated into a benchtop system, which was shown to provide the necessary stroke requirements of approx.0.125 inches for the targeted surge-control application. Cycle times for the actuator were limited to 4 seconds due to control and cooling constraints but this cycle time was determined to be adequate for the surge control application targeted as the primary requirement was initial actuation of a surge control rod, which could be completed in approximately one second.
Nb 3Sn RRP® strand and Rutherford cable development for a 15 T dipole demonstrator
Barzi, E.; Andreev, N.; Li, P.; ...
2016-03-16
Keystoned Rutherford cables made of 28 strands and with a stainless steel core were developed and manufactured using 1 mm Nb3Sn composite wires produced by Oxford Superconducting Technology with 127 and 169 restacks using the Restacked-Rod-Process ®. Furthermore, the performance and properties of these cables were studied to evaluate possible candidates for 15 T accelerator magnets.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Repetto, G.; Dominguez, C.; Durville, B.
The safety principle in case of a LOCA is to preserve the short and long term coolability of the core. The associated safety requirements are to ensure the resistance of the fuel rods upon quench and post-quench loads and to maintain a coolable geometry in the core. An R&D program has been launched by IRSN with the support of EDF, to perform both experimental and modeling activities in the frame of the LOCA transient, on technical issues such as: - flow blockage within a fuel rods bundle and its potential impact on coolability, - fuel fragment relocation in the balloonedmore » areas: its potential impact on cladding PCT (Peak Cladding Temperature) and on the maximum oxidation rate, - potential loss of cladding integrity upon quench and post-quench loads. The PERFROI project (2014-2019) focusing on the first above issue, is structured in two axes: 1. axis 1: thermal mechanical behavior of deformation and rupture of cladding taking into account the contact between fuel rods; specific research at LaMCoS laboratory focus on the hydrogen behavior in cladding alloys and its impact on the mechanical behavior of the rod; and, 2. axis 2: thermal hydraulics study of a partially blocked region of the core (ballooned area taking into account the fuel relocation with local over power), during cooling phase by water injection; More detailed activities foreseen in collaboration with LEMTA laboratory will focus on the characterization of two phase flows with heat transfer in deformed structures.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Triplett, C.E.
1996-12-01
This thesis presents the results of an experimental investigation of natural convection heat transfer in a staggered array of heated cylinders, oriented horizontally within a rectangular enclosure. The main purpose of this research was to extend the knowledge of heat transfer within enclosed bundles of spent nuclear fuel rods sealed within a shipping or storage container. This research extends Canaan`s investigation of an aligned array of heated cylinders that thermally simulated a boiling water reactor (BWR) spent fuel assembly sealed within a shipping or storage cask. The results are presented in terms of piecewise Nusselt-Rayleigh number correlations of the formmore » Nu = C(Ra){sup n}, where C and n are constants. Correlations are presented both for individual rods within the array and for the array as a whole. The correlations are based only on the convective component of the heat transfer. The radiative component was calculated with a finite-element code that used measured surface temperatures, rod array geometry, and measured surface emissivities as inputs. The correlation results are compared to Canaan`s aligned array results and to other studies of natural convection in horizontal tube arrays.« less
Spontaneous formation of non-uniform double helices for elastic rods under torsion
NASA Astrophysics Data System (ADS)
Li, Hongyuan; Zhao, Shumin; Xia, Minggang; He, Siyu; Yang, Qifan; Yan, Yuming; Zhao, Hanqiao
2017-02-01
The spontaneous formation of double helices for filaments under torsion is common and significant. For example, the research on the supercoiling of DNA is helpful for understanding the replication and transcription of DNA. Similar double helices can appear in carbon nanotube yarns, cables, telephone wires and so forth. We noticed that non-uniform double helices can be produced due to the surface friction induced by the self-contact. Therefore an ideal model was presented to investigate the formation of double helices for elastic rods under torque. A general equilibrium condition which is valid for both the smooth surface and the rough surface situations is derived by using the variational method. By adding further constraints, the smooth and rough surface situations are investigated in detail respectively. Additionally, the model showed that the specific process of how to twist and slack the rod can determine the surface friction and hence influence the configuration of the double helix formed by rods with rough surfaces. Based on this principle, a method of manufacturing double helices with designed configurations was proposed and demonstrated. Finally, experiments were performed to verify the model and the results agreed well with the theory.
The Role of Phase Changes in TiO2/Pt/TiO2 Filaments
NASA Astrophysics Data System (ADS)
Bíró, Ferenc; Hajnal, Zoltán; Dücső, Csaba; Bársony, István
2018-04-01
This work analyses the role of phase changes in TiO2/Pt/TiO2 layer stacks for micro-heater application regarding their stability and reliable operation. The polycrystalline Pt layer wrapped in a TiO2 adhesion layer underwent a continuous recrystallisation in a self-heating operation causing a drift in the resistance ( R) versus temperature ( T) performance. Simultaneously, the TiO2 adhesion layer also deteriorates at high temperature by phase changes from amorphous to anatase and rutile crystallite formation, which not only influences the Pt diffusion in different migration phenomena, but also reduces the cross section of the Pt heater wire. Thorough scanning electron microscopy, energy dispersive spectroscopy, cross-sectional transmission electron microscopy (XTEM) and electron beam diffraction analysis of the structures operated at increasing temperature revealed the elemental structural processes leading to the instabilities and the accelerated degradation, resulting in rapid breakdown of the heater wire. Owing to stability and reliability criteria, the conditions for safe operation of these layer structures could be determined.
New mouse model of skeletal muscle atrophy using spiral wire immobilization.
Onda, Akiko; Kono, Hajime; Jiao, Qibin; Akimoto, Takayuki; Miyamoto, Toshikazu; Sawada, Yasuhiro; Suzuki, Katsuhiko; Kusakari, Yoichiro; Minamisawa, Susumu; Fukubayashi, Toru
2016-10-01
Disuse-induced skeletal muscle atrophy is a serious concern; however, there is not an effective mouse model to elucidate the molecular mechanisms. We developed a noninvasive atrophy model in mice. After the ankle joints of mice were bandaged into a bilateral plantar flexed position, either bilateral or unilateral hindlimbs were immobilized by wrapping in bonsai steel wire. After 3, 5, or 10 days of immobilization of the hip, knee, and ankle, the weight of the soleus and plantaris muscles decreased significantly in both bilateral and unilateral immobilization. MAFbx/atrogin-1 and MuRF1 mRNA was found to have significantly increased in both muscles, consistent with disuse-induced atrophy. Notably, the procedure did not result in either edema or necrosis in the fixed hindlimbs. This method allows repeated, direct access to the immobilized muscle, making it a useful procedure for concurrent application and assessment of various therapeutic interventions. Muscle Nerve 54: 788-791, 2016. © 2016 Wiley Periodicals, Inc.