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Sample records for plate peale sattusid

  1. Pathology in skeletons of Peale's dolphin Lagenorhynchus australis from southern South America.

    PubMed

    San Martín, Analía A; Macnie, Silvina V; Goodall, R Natalie P; Boy, Claudia C

    2016-06-15

    Peale's dolphin Lagenorhynchus australis is frequently seen off the coast of southern South America, where it feeds among coastal kelp beds and occasionally strands. We searched for macroscopic evidence of skeletal lesions in 78 specimens of Peale's dolphin from 2 museum collections, which contain almost all of the species' skeletons known in collections worldwide. Thirty-two specimens (41%) had some type of osteological abnormalities. In 21 cases (66%), congenital deformations were the most predominant abnormality found. Acquired lesions included (1) induced trauma: abnormal curvature (n=5 specimens) and fractures (n=2); (2) infectious diseases: spondylo-osteomyelitis (n=3); and (3) degenerative diseases: exostoses (n=8) and spondylosis deformans (n=4). It is noteworthy that all of these animals died incidentally in gillnet entanglement and were presumably healthy at the time of death. The effect that different osseous lesions may have on an animal's quality of life may depend on the area of the spine affected and the number of vertebrae involved. PMID:27304866

  2. Enhanced delivery of PEAL nanoparticles with ultrasound targeted microbubble destruction mediated siRNA transfection in human MCF-7/S and MCF-7/ADR cells in vitro

    PubMed Central

    Teng, Yanwei; Bai, Min; Sun, Ying; Wang, Qi; Li, Fan; Xing, Jinfang; Du, Lianfang; Gong, Tao; Duan, Yourong

    2015-01-01

    The gene knockdown activity of small interfering RNA (siRNA) has led to their use as potential therapeutics for a variety of diseases. However, successful gene therapy requires safe and efficient delivery systems. In this study, we choose mPEG-PLGA-PLL nanoparticles (PEAL NPs) with ultrasound targeted microbubble destruction (UTMD) to efficiently deliver siRNA into cells. An emulsification-solvent evaporation method was used to prepare siRNA-loaded PEAL NPs. The NPs possessed an average size of 132.6±10.3 nm (n=5), with a uniform spherical shape, and had an encapsulation efficiency (EE) of more than 98%. As demonstrated by MTT assay, neither PEAL NPs nor siRNA-loaded PEAL NPs showed cytotoxicity even at high concentrations. The results of cellular uptake showed, with the assistance of UTMD, the siRNA-loaded PEAL NPs can be effectively internalized and can subsequently release siRNA in cells. Taken together, PEAL NPs with UTMD may be highly promising for siRNA delivery, making it possible to fully exploit the potential of siRNA-based therapeutics. PMID:26346350

  3. Enhanced delivery of PEAL nanoparticles with ultrasound targeted microbubble destruction mediated siRNA transfection in human MCF-7/S and MCF-7/ADR cells in vitro.

    PubMed

    Teng, Yanwei; Bai, Min; Sun, Ying; Wang, Qi; Li, Fan; Xing, Jinfang; Du, Lianfang; Gong, Tao; Duan, Yourong

    2015-01-01

    The gene knockdown activity of small interfering RNA (siRNA) has led to their use as potential therapeutics for a variety of diseases. However, successful gene therapy requires safe and efficient delivery systems. In this study, we choose mPEG-PLGA-PLL nanoparticles (PEAL NPs) with ultrasound targeted microbubble destruction (UTMD) to efficiently deliver siRNA into cells. An emulsification-solvent evaporation method was used to prepare siRNA-loaded PEAL NPs. The NPs possessed an average size of 132.6±10.3 nm (n=5), with a uniform spherical shape, and had an encapsulation efficiency (EE) of more than 98%. As demonstrated by MTT assay, neither PEAL NPs nor siRNA-loaded PEAL NPs showed cytotoxicity even at high concentrations. The results of cellular uptake showed, with the assistance of UTMD, the siRNA-loaded PEAL NPs can be effectively internalized and can subsequently release siRNA in cells. Taken together, PEAL NPs with UTMD may be highly promising for siRNA delivery, making it possible to fully exploit the potential of siRNA-based therapeutics. PMID:26346350

  4. Echolocation in sympatric Peale's dolphins (Lagenorhynchus australis) and Commerson's dolphins (Cephalorhynchus commersonii) producing narrow-band high-frequency clicks.

    PubMed

    Kyhn, L A; Jensen, F H; Beedholm, K; Tougaard, J; Hansen, M; Madsen, P T

    2010-06-01

    An increasing number of smaller odontocetes have recently been shown to produce stereotyped narrow-band high-frequency (NBHF) echolocation clicks. Click source parameters of NBHF clicks are very similar, and it is unclear whether the sonars of individual NBHF species are adapted to specific habitats or the presence of other NBHF species. Here, we test whether sympatric NBHF species sharing the same habitat show similar adaptations in their echolocation clicks and whether their clicks display signs of character displacement. Wide-band sound recordings were obtained with a six-element hydrophone array from wild Peale's (Lagenorhynchus australis) and Commerson's (Cephalorhynchus commersonii) dolphins off the Falkland Islands. The centroid frequency was different between Commerson's (133+/-2 kHz) and Peale's (129+/-3 kHz) dolphins. The r.m.s. bandwidth was 12+/-3 kHz for both species. The source level was higher for Peale's dolphin (185+/-6 dB re 1 muPa p.-p.) than for Commerson's (177+/-5 dB re 1 muPa p.-p.). The mean directivity indexes were 25 dB for both species. The relatively low source levels in combination with the high directivity index may be an adaptation to reduce clutter when foraging in a coastal environment. We conclude that the small species-specific shifts in distribution of centroid frequencies around 130 kHz may reflect character displacement in otherwise-stereotyped NBHF clicks. PMID:20472781

  5. The Stephen H. Long Expedition (1819?1820), Titian R. Peale?s field illustrations, and the lost holotypes of the North American shrews Sorex brevicaudus Say and Sorex parvus Say (Mammalia: Soricidae) from the Philadelphia Museum

    USGS Publications Warehouse

    Woodman, N.

    2009-01-01

    While encamped for the winter of 1819?1820 at Engineer Cantonment along the Missouri River in present-day eastern Nebraska, members of Major Stephen Harriman Long?s Expedition to the Rocky Mountains collected a number of animals that were previously unknown. Among the mammals were two soricids that were subsequently described by Thomas Say as Sorex brevicaudus (Northern Short-tailed Shrew, Blarina brevicauda) and Sorex parvus (Least Shrew, Cryptotis parvus). The holotypes of these species were deposited and placed on public exhibit in the Philadelphia Museum, the predominant North American systematic collection of the early nineteenth century. Like most private museums of that era, the Philadelphia Museum eventually went out of business, and its collections were dispersed and, for the most part, lost. Fortunately, Titian R. Peale made a detailed field sketch of the two specimens soon after their capture and subsequently executed a watercolor based on that sketch. In addition, an engraving of the holotypes was published in the decade following the discovery of the two species. Illustrations of holotypes are taxonomically useful when they depict diagnostic characters of species. They take on added taxonomic significance in the absence of the holotypes. In the cases of Sorex brevicaudus and Sorex parvus, pictures provide strong confirmation of the taxonomic identities of these two species, as well as recording the early history of the specimens.

  6. Plate motion

    SciTech Connect

    Gordon, R.G. )

    1991-01-01

    The motion of tectonic plates on the earth is characterized in a critical review of U.S. research from the period 1987-1990. Topics addressed include the NUVEL-1 global model of current plate motions, diffuse plate boundaries and the oceanic lithosphere, the relation between plate motions and distributed deformations, accelerations and the steadiness of plate motions, the distribution of current Pacific-North America motion across western North America and its margin, plate reconstructions and their uncertainties, hotspots, and plate dynamics. A comprehensive bibliography is provided. 126 refs.

  7. Peen plating

    NASA Technical Reports Server (NTRS)

    Babecki, A. J. (Inventor); Haehner, C. L.

    1973-01-01

    A process for metal plating which comprises spraying a mixture of metallic powder and small peening particles at high velocity against a surface is described. The velocity must be sufficient to impact and bond metallic powder onto the surface. In the case of metal surfaces, the process has as one of its advantages providing mechanical working (hardening) of the surface simultaneously with the metal plating.

  8. Sputtering and ion plating

    NASA Technical Reports Server (NTRS)

    1972-01-01

    The proceedings of a conference on sputtering and ion plating are presented. Subjects discussed are: (1) concepts and applications of ion plating, (2) sputtering for deposition of solid film lubricants, (3) commercial ion plating equipment, (4) industrial potential for ion plating and sputtering, and (5) fundamentals of RF and DC sputtering.

  9. Earth's Decelerating Tectonic Plates

    SciTech Connect

    Forte, A M; Moucha, R; Rowley, D B; Quere, S; Mitrovica, J X; Simmons, N A; Grand, S P

    2008-08-22

    Space geodetic and oceanic magnetic anomaly constraints on tectonic plate motions are employed to determine a new global map of present-day rates of change of plate velocities. This map shows that Earth's largest plate, the Pacific, is presently decelerating along with several other plates in the Pacific and Indo-Atlantic hemispheres. These plate decelerations contribute to an overall, globally averaged slowdown in tectonic plate speeds. The map of plate decelerations provides new and unique constraints on the dynamics of time-dependent convection in Earth's mantle. We employ a recently developed convection model constrained by seismic, geodynamic and mineral physics data to show that time-dependent changes in mantle buoyancy forces can explain the deceleration of the major plates in the Pacific and Indo-Atlantic hemispheres.

  10. ASSEMBLY OF PARALLEL PLATES

    DOEpatents

    Groh, E.F.; Lennox, D.H.

    1963-04-23

    This invention is concerned with a rigid assembly of parallel plates in which keyways are stamped out along the edges of the plates and a self-retaining key is inserted into aligned keyways. Spacers having similar keyways are included between adjacent plates. The entire assembly is locked into a rigid structure by fastening only the outermost plates to the ends of the keys. (AEC)

  11. Accelerated plate tectonics.

    PubMed

    Anderson, D L

    1975-03-21

    The concept of a stressed elastic lithospheric plate riding on a viscous asthenosphere is used to calculate the recurrence interval of great earthquakes at convergent plate boundaries, the separation of decoupling and lithospheric earthquakes, and the migration pattern of large earthquakes along an arc. It is proposed that plate motions accelerate after great decoupling earthquakes and that most of the observed plate motions occur during short periods of time, separated by periods of relative quiescence. PMID:17799689

  12. Plating Tank Control Software

    Energy Science and Technology Software Center (ESTSC)

    1998-03-01

    The Plating Tank Control Software is a graphical user interface that controls and records plating process conditions for plating in high aspect ratio channels that require use of low current and long times. The software is written for a Pentium II PC with an 8 channel data acquisition card, and the necessary shunt resistors for measuring currents in the millampere range.

  13. Rotatable shear plate interferometer

    DOEpatents

    Duffus, Richard C.

    1988-01-01

    A rotatable shear plate interferometer comprises a transparent shear plate mounted obliquely in a tubular supporting member at 45.degree. with respect to its horizontal center axis. This tubular supporting member is supported rotatably around its center axis and a collimated laser beam is made incident on the shear plate along this center axis such that defocus in different directions can be easily measured.

  14. An improved plating process

    NASA Technical Reports Server (NTRS)

    Askew, John C.

    1994-01-01

    An alternative to the immersion process for the electrodeposition of chromium from aqueous solutions on the inside diameter (ID) of long tubes is described. The Vessel Plating Process eliminates the need for deep processing tanks, large volumes of solutions, and associated safety and environmental concerns. Vessel Plating allows the process to be monitored and controlled by computer thus increasing reliability, flexibility and quality. Elimination of the trivalent chromium accumulation normally associated with ID plating is intrinsic to the Vessel Plating Process. The construction and operation of a prototype Vessel Plating Facility with emphasis on materials of construction, engineered and operational safety and a unique system for rinse water recovery are described.

  15. Paper microzone plates.

    PubMed

    Carrilho, Emanuel; Phillips, Scott T; Vella, Sarah J; Martinez, Andres W; Whitesides, George M

    2009-08-01

    This paper describes 96- and 384-microzone plates fabricated in paper as alternatives to conventional multiwell plates fabricated in molded polymers. Paper-based plates are functionally related to plastic well plates, but they offer new capabilities. For example, paper-microzone plates are thin (approximately 180 microm), require small volumes of sample (5 microL per zone), and can be manufactured from inexpensive materials ($0.05 per plate). The paper-based plates are fabricated by patterning sheets of paper, using photolithography, into hydrophilic zones surrounded by hydrophobic polymeric barriers. This photolithography used an inexpensive formulation photoresist that allows rapid (approximately 15 min) prototyping of paper-based plates. These plates are compatible with conventional microplate readers for quantitative absorbance and fluorescence measurements. The limit of detection per zone loaded for fluorescence was 125 fmol for fluorescein isothiocyanate-labeled bovine serum albumin, and this level corresponds to 0.02 the quantity of analyte per well used to achieve comparable signal-to-noise in a 96-well plastic plate (using a solution of 25 nM labeled protein). The limits of detection for absorbance on paper was approximately 50 pmol per zone for both Coomassie Brilliant Blue and Amaranth dyes; these values were 0.4 that required for the plastic plate. Demonstration of quantitative colorimetric correlations using a scanner or camera to image the zones and to measure the intensity of color, makes it possible to conduct assays without a microplate reader. PMID:19572563

  16. Multicolor printing plate joining

    NASA Technical Reports Server (NTRS)

    Waters, W. J. (Inventor)

    1984-01-01

    An upper plate having ink flow channels and a lower plate having a multicolored pattern are joined. The joining is accomplished without clogging any ink flow paths. A pattern having different colored parts and apertures is formed in a lower plate. Ink flow channels each having respective ink input ports are formed in an upper plate. The ink flow channels are coated with solder mask and the bottom of the upper plate is then coated with solder. The upper and lower plates are pressed together at from 2 to 5 psi and heated to a temperature of from 295 F to 750 F or enough to melt the solder. After the plates have cooled and the pressure is released, the solder mask is removed from the interior passageways by means of a liquid solvent.

  17. Hypervelocity plate acceleration

    SciTech Connect

    Marsh, S.P.; Tan, T.H.

    1991-01-01

    Shock tubes have been used to accelerate 1.5-mm-thick stainless steel plates to high velocity while retaining their integrity. The fast shock tubes are 5.1-cm-diameter, 15.2-cm-long cylinders of PBX-9501 explosive containing a 1.1-cm-diameter cylindrical core of low-density polystyrene foam. The plates have been placed directly in contact with one face of the explosive system. Plane-wave detonation was initiated on the opposite face. A Mach disk was formed in the imploding styrofoam core, which provided the impulse required to accelerate the metal plate to high velocity. Parametric studies were made on this system to find the effect of varying plate metal, plate thickness, foam properties, and addition of a barrel. A maximum plate velocity of 9.0 km/s has been observed. 6 refs., 17 figs.

  18. WFPDB: European Plate Archives

    NASA Astrophysics Data System (ADS)

    Tsvetkov, Milcho

    2007-08-01

    The Wide-Field Plate Database (WFPDB) gives an inventory of all wide-field (>~ 1 sq. deg) photographic observations archived in astronomical institutions over the world. So it facilitates and stimulates their use and preservation as a valuable source of information for future investigations in astronomy. At present WFPDB manages plate-index information for 25% of all existing plates providing on-line access from Sofia (http://www.skyarchive.org/search) and in CDS, Strasbourg. Here we present the new development of WFPDB as an instrument for searching of long term brightness variations of different sky objects stressing on the European photographic plate collections (from existing 2 million wide-field plates more than 55% are in Europe: Germany, Russia, Ukraine, Italy, Czech Republic, etc.). We comment examples of digitization (with flatbed scanners) of the European plate archives in Sonneberg, Pulkovo, Asiago, Byurakan, Bamberg, etc. and virtual links of WFPDB with European AVO, ADS, IBVS.

  19. GOLD PLATING PROCESS

    DOEpatents

    Seegmiller, R.

    1957-08-01

    An improved bath is reported for plating gold on other metals. The composition of the plating bath is as follows: Gold cyanide from about 15 to about 50 grams, potassium cyanide from about 70 to about 125 grams, and sulfonated castor oil from about 0.1 to about 10 cc. The gold plate produced from this bath is smooth, semi-hard, and nonporous.

  20. Plating methods, a survey

    NASA Technical Reports Server (NTRS)

    Berkowitz, J. B.; Emerson, N. H.

    1972-01-01

    Results are presented of a comprehensive search of the literature available, much of which has been generated by the research centers of NASA and its contractors, on plating and coating methods and techniques. Methods covered included: (1) electroplating from aqueous solutions; (2) electroplating from nonaqueous solutions; (3) electroplating from fused-salt baths; (4) electroforming; (5) electroless plating, immersion plating, and mirroring; (6) electroplating from gaseous plasmas; and (7) anodized films and conversion coatings.

  1. CALUTRON FACE PLATE

    DOEpatents

    Brobeck, W.M.

    1959-08-25

    The construction of a removable cover plate for a calutron tank is described. The plate is fabricated of a rectangular frame member to which is welded a bowed or dished plate of thin steel, reinforced with transverse stiffening ribs. When the tank is placed between the poles of a magnet, the plate may be pivoted away from the tank and magnet and is adapted to support the ion separation mechanism secured to its inner side as well as the vacuum load within the tank.

  2. PLATES WITH OXIDE INSERTS

    DOEpatents

    West, J.M.; Schumar, J.F.

    1958-06-10

    Planar-type fuel assemblies for nuclear reactors are described, particularly those comprising fuel in the oxide form such as thoria and urania. The fuel assembly consists of a plurality of parallel spaced fuel plate mennbers having their longitudinal side edges attached to two parallel supporting side plates, thereby providing coolant flow channels between the opposite faces of adjacent fuel plates. The fuel plates are comprised of a plurality of longitudinally extending tubular sections connected by web portions, the tubular sections being filled with a plurality of pellets of the fuel material and the pellets being thermally bonded to the inside of the tubular section by lead.

  3. Blue Willow Story Plates

    ERIC Educational Resources Information Center

    Fontes, Kris

    2009-01-01

    In the December 1997 issue of "SchoolArts" is a lesson titled "Blue Willow Story Plates" by Susan Striker. In this article, the author shares how she used this lesson with her middle-school students many times over the years. Here, she describes a Blue Willow plate painting project that her students made.

  4. Earthquakes and plate tectonics

    USGS Publications Warehouse

    Spall, H.

    1977-01-01

    An explanation is to be found in plate tectonics, a concept which has revolutionized thinking in the Earth sciences in the last 10 years. The theory of plate tectonics combines many of the ideas about continental drift (originally proposed in 1912 by Alfred Wegener in Germany) and sea-floor spreading (suggested originally by Harry Hess of Princeton University). 

  5. Turbine vane plate assembly

    DOEpatents

    Schiavo Jr., Anthony L.

    2006-01-10

    A turbine vane assembly includes a turbine vane having first and second shrouds with an elongated airfoil extending between. Each end of the airfoil transitions into a shroud at a respective junction. Each of the shrouds has a plurality of cooling passages, and the airfoil has a plurality of cooling passages extending between the first and second shrouds. A substantially flat inner plate and an outer plate are coupled to each of the first and second shrouds so as to form inner and outer plenums. Each inner plenum is defined between at least the junction and the substantially flat inner plate; each outer plenum is defined between at least the substantially flat inner plate and the outer plate. Each inner plenum is in fluid communication with a respective outer plenum through at least one of the cooling passages in the respective shroud.

  6. Earthquakes and plate tectonics.

    USGS Publications Warehouse

    Spall, H.

    1982-01-01

    Earthquakes occur at the following three kinds of plate boundary: ocean ridges where the plates are pulled apart, margins where the plates scrape past one another, and margins where one plate is thrust under the other. Thus, we can predict the general regions on the earth's surface where we can expect large earthquakes in the future. We know that each year about 140 earthquakes of magnitude 6 or greater will occur within this area which is 10% of the earth's surface. But on a worldwide basis we cannot say with much accuracy when these events will occur. The reason is that the processes in plate tectonics have been going on for millions of years. Averaged over this interval, plate motions amount to several mm per year. But at any instant in geologic time, for example the year 1982, we do not know, exactly where we are in the worldwide cycle of strain build-up and strain release. Only by monitoring the stress and strain in small areas, for instance, the San Andreas fault, in great detail can we hope to predict when renewed activity in that part of the plate tectonics arena is likely to take place. -from Author

  7. Lohse's historic plate archive

    NASA Astrophysics Data System (ADS)

    Tsvetkov, M.; Tsvetkova, K.; Richter, G.; Scholz, G.; Böhm, P.

    The description and the analysis of Oswald Lohse's astrophotographic plates, collected at the Astrophysical Observatory Potsdam in the period 1879 - 1889, are presented. 67 plates of the archive, taken with the greatest instrument of the observatory at that time - the refractor (D = 0.30 m, F = 5.40 m, scale = 38''/mm) and with the second heliographic objective (D = 0.13 m, F = 1.36 m, scale = 152''/mm) - - survived two world wars in relative good condition. The plate emulsions are from different manufacturers in the beginning of astrophotography (Gädicke, Schleussner, Beernaert, etc.). The sizes of the plates are usually 9x12 cm2, which corresponds to fields of 1.2deg and 5deg respectively for each instrument mentioned above. The average limiting magnitude is 13.0(pg). Besides of the plates received for technical experiments (work on photographic processes, testing of new instruments and methods of observations), the scientific observations follow programs for studies of planet surfaces, bright stars, some double stars, stellar clusters and nebulous objects. Lohse's archive is included into the Wide Field Plate Database (http://www.skyarchive.org) as the oldest systematic one, covering the fields of Orion (M42/43), Pleiades, h & chi Persei, M37, M3, M11, M13, M92, M31, etc. With the PDS 2020 GM+ microdensitometer of Münster University 10 archive plates were digitized.

  8. Tectonic Plate Movement.

    ERIC Educational Resources Information Center

    Landalf, Helen

    1998-01-01

    Presents an activity that employs movement to enable students to understand concepts related to plate tectonics. Argues that movement brings topics to life in a concrete way and helps children retain knowledge. (DDR)

  9. Flat plate solar oven

    SciTech Connect

    Parikh, M.

    1981-01-01

    The construction of an Indian Rs. 186 (US $20.33) flat-plate solar oven is described. Detailed drawings are provided and relevant information on cooking times and temperature for different foods is given.

  10. Plate tectonics: Metamorphic myth

    NASA Astrophysics Data System (ADS)

    Korenaga, Jun

    2016-01-01

    Clear evidence for subduction-induced metamorphism, and thus the operation of plate tectonics on the ancient Earth has been lacking. Theoretical calculations indicate that we may have been looking for something that cannot exist.

  11. Violin plate modes.

    PubMed

    Gough, Colin

    2015-01-01

    As the first step toward developing a generic model for the acoustically radiating vibrational modes of the violin and related instruments, the modes of both freely supported and edge-constrained top and back plates have been investigated as functions of shape, arching height, elastic anisotropy, the f-holes and associated island area, thickness graduations, and the additional boundary constraints of the ribs, soundpost, and bass-bar present in the assembled instrument. Comsol shell structure finite element software has been used as a quasi-experimental tool, with physical and geometric properties varied smoothly, often over several orders of magnitude, allowing the development of the plate modes to be followed continuously from those of an initially square plate to those of doubly-arched, guitar-shaped, orthotropic plates and their dependence on all the above factors. PMID:25618046

  12. Positive battery plate

    NASA Technical Reports Server (NTRS)

    Rowlette, John R. (Inventor)

    1985-01-01

    The power characteristics of a lead acid battery are improved by incorporating a dispersion of 1 to 10% by weight of a thermodynamically stable conductivity additive, such as conductive tin oxide coated glass fibers (34) of filamentary glass wool (42) in the positive active layer (32) carried on the grid (30) of the positive plate (16). Positive plate potential must be kept high enough to prevent reduction of the tin oxide to tin by utilizing an oversized, precharged positive paste.

  13. Fractal multifiber microchannel plates

    NASA Technical Reports Server (NTRS)

    Cook, Lee M.; Feller, W. B.; Kenter, Almus T.; Chappell, Jon H.

    1992-01-01

    The construction and performance of microchannel plates (MCPs) made using fractal tiling mehtods are reviewed. MCPs with 40 mm active areas having near-perfect channel ordering were produced. These plates demonstrated electrical performance characteristics equivalent to conventionally constructed MCPs. These apparently are the first MCPs which have a sufficiently high degree of order to permit single channel addressability. Potential applications for these devices and the prospects for further development are discussed.

  14. Phononic plate waves.

    PubMed

    Wu, Tsung-Tsong; Hsu, Jin-Chen; Sun, Jia-Hong

    2011-10-01

    In the past two decades, phononic crystals (PCs) which consist of periodically arranged media have attracted considerable interest because of the existence of complete frequency band gaps and maneuverable band structures. Recently, Lamb waves in thin plates with PC structures have started to receive increasing attention for their potential applications in filters, resonators, and waveguides. This paper presents a review of recent works related to phononic plate waves which have recently been published by the authors and coworkers. Theoretical and experimental studies of Lamb waves in 2-D PC plate structures are covered. On the theoretical side, analyses of Lamb waves in 2-D PC plates using the plane wave expansion (PWE) method, finite-difference time-domain (FDTD) method, and finite-element (FE) method are addressed. These methods were applied to study the complete band gaps of Lamb waves, characteristics of the propagating and localized wave modes, and behavior of anomalous refraction, called negative refraction, in the PC plates. The theoretical analyses demonstrated the effects of PC-based negative refraction, lens, waveguides, and resonant cavities. We also discuss the influences of geometrical parameters on the guiding and resonance efficiency and on the frequencies of waveguide and cavity modes. On the experimental side, the design and fabrication of a silicon-based Lamb wave resonator which utilizes PC plates as reflective gratings to form the resonant cavity are discussed. The measured results showed significant improvement of the insertion losses and quality factors of the resonators when the PCs were applied. PMID:21989878

  15. Caribbean plate interactions

    SciTech Connect

    Ball, M. )

    1993-02-01

    Vector analysis of plate motions, derived from studies of Atlantic magnetic lineations and fracture zone trends, indicates the following relative movements between the Caribbean, North American, and South American Plates. (1) During Early Jurassic to Early Cretaceous, the North American Plate moved 1900 km westward and 900 km northward relative to the South American Plate. A broad zone including the Caribbean region, i.e., the zone between the North and South America Plates, was a site of left-lateral shear and north-south extension. (2) During Early Cretaceous to Late Cretaceous, the North American Mate moved an additional 1200 km westward relative to South America across this zone. (3) During Late Cretaceous to the end of the Eocene, the North American Plate moved 200 km westward and 400 km northward relative to the South American Plate. (4) From the end of the Eocene to near the end of the Miocene, North America converged on South America some 200 km and moved 100 km eastward relative to it. Through the Mesozoic and earliest Tertiary history of the Caribbean, the region was a shear zone within which left-lateral displacement exceeded 3000 km and north-south extension exceeded 1300 km. In regard to time, 80% of the history of the Caribbean region is one of north-south extension and left-lateral shear. In terms of space, 97% of the shear is left-lateral and the ratio of divergence versus convergence is 7 to 1. Thus, characterizing the Caribbean region, and the Atlantic to its east, as a zone of north-south extension and left-lateral shear, is a fair generalization.

  16. Using Plate Mapping to Examine Portion Size and Plate Composition for Large and Small Divided Plates

    PubMed Central

    Sharp, David E.; Sobal, Jeffery; Wansink, Brian

    2015-01-01

    Does the size of a plate influence the serving of all items equally, or does it influence the serving of some foods – such as meat versus starch versus vegetables – very differently? To examine this, we utilize a promising new plate mapping method where people drew a meal on a paper plate to examine sensitivity to small versus large three-compartment divided plates in portion size and meal composition in a sample of 109 university students. The total drawn meal area was 37% bigger on large plates than small plates, that is, the portion of plate coverage did not differ by plate size. Men and women drew bigger vegetable portions and men drew bigger meat portions on large plates when compared to small plates. These results suggest that men and women are differentially sensitive to plate size for overall meal size and for meal composition. Implications for decreasing portion size and improving meal balance are discussed. PMID:25280373

  17. Cadmium plating replacements

    SciTech Connect

    Nelson, M.J.; Groshart, E.C.

    1995-03-01

    The Boeing Company has been searching for replacements to cadmium plate. Two alloy plating systems seem close to meeting the needs of a cadmium replacement. The two alloys, zinc-nickel and tin-zinc are from alloy plating baths; both baths are neutral pH. The alloys meet the requirements for salt fog corrosion resistance, and both alloys excel as a paint base. Currently, tests are being performed on standard fasteners to compare zinc-nickel and tin-zinc on threaded hardware where cadmium is heavily used. The Hydrogen embrittlement propensity of the zinc-nickel bath has been tested, and just beginning for the tin-zinc bath. Another area of interest is the electrical properties on aluminum for tin-zinc and will be discussed. The zinc-nickel alloy plating bath is in production in Boeing Commercial Airplane Group for non-critical low strength steels. The outlook is promising that these two coatings will help The Boeing Company significantly reduce its dependence on cadmium plating.

  18. Cadmium plating replacements

    NASA Technical Reports Server (NTRS)

    Nelson, Mary J.; Groshart, Earl C.

    1995-01-01

    The Boeing Company has been searching for replacements to cadmium plate. Two alloy plating systems seem close to meeting the needs of a cadmium replacement. The two alloys, zinc-nickel and tin-zinc are from alloy plating baths; both baths are neutral pH. The alloys meet the requirements for salt fog corrosion resistance, and both alloys excel as a paint base. Currently, tests are being performed on standard fasteners to compare zinc-nickel and tin-zinc on threaded hardware where cadmium is heavily used. The Hydrogen embrittlement propensity of the zinc-nickel bath has been tested, and just beginning for the tin-zinc bath. Another area of interest is the electrical properties on aluminum for tin-zinc and will be discussed. The zinc-nickel alloy plating bath is in production in Boeing Commercial Airplane Group for non-critical low strength steels. The outlook is promising that these two coatings will help The Boeing Company significantly reduce its dependence on cadmium plating.

  19. Bipolar battery plate

    NASA Technical Reports Server (NTRS)

    Rowlette, John J. (Inventor)

    1987-01-01

    A liquid-impermeable plate (10) having through-plate conductivity with essentially zero resistance comprises an insulator sheet (12) having a series of spaced perforations (14) each of which contains a metal element (16) sealingly received into the perforation (14). A low-cost plate can readily be manufactured by punching a thermoplastic sheet (40) such as polypropylene with a punching tool (52), filling the apertures with led spheres (63) having a diameter smaller than the holes (50) but larger than the thickness of the sheet, sweeping excess spheres (62) off the sheet with a doctor blade (60) and then pressing a heated platen (74) onto the sheet to swage the spheres into a cylindrical shape and melt the surrounding resin to form a liquid-impermeable collar (4) sealing the metal into the sheet.

  20. Nitrided Metallic Bipolar Plates

    SciTech Connect

    Brady, Michael P; Tortorelli, Peter F; Pihl, Josh A; Toops, Todd J; More, Karren Leslie; Meyer III, Harry M; Vitek, John Michael; Wang, Heli; Turner, John; Wilson, Mahlon; Garzon, Fernando; Rockward, Tommy; Connors, Dan; Rakowski, Jim; Gervasio, Don

    2008-01-01

    The objectives are: (1) Develop and optimize stainless steel alloys amenable to formation of a protective Cr-nitride surface by gas nitridation, at a sufficiently low cost to meet DOE targets and with sufficient ductility to permit manufacture by stamping. (2) Demonstrate capability of nitridation to yield high-quality stainless steel bipolar plates from thin stamped alloy foils (no significant stamped foil warping or embrittlement). (3) Demonstrate single-cell fuel cell performance of stamped and nitrided alloy foils equivalent to that of machined graphite plates of the same flow-field design ({approx}750-1,000 h, cyclic conditions, to include quantification of metal ion contamination of the membrane electrode assembly [MEA] and contact resistance increase attributable to the bipolar plates). (4) Demonstrate potential for adoption in automotive fuel cell stacks. Thin stamped metallic bipolar plates offer the potential for (1) significantly lower cost than currently-used machined graphite bipolar plates, (2) reduced weight/volume, and (3) better performance and amenability to high volume manufacture than developmental polymer/carbon fiber and graphite composite bipolar plates. However, most metals exhibit inadequate corrosion resistance in proton exchange membrane fuel cell (PEMFC) environments. This behavior leads to high electrical resistance due to the formation of surface oxides and/or contamination of the MEA by metallic ions, both of which can significantly degrade fuel cell performance. Metal nitrides offer electrical conductivities up to an order of magnitude greater than that of graphite and are highly corrosion resistant. Unfortunately, most conventional coating methods (for metal nitrides) are too expensive for PEMFC stack commercialization or tend to leave pinhole defects, which result in accelerated local corrosion and unacceptable performance.

  1. Plate-mantle coupling from post-Pangea plate kinematics

    NASA Astrophysics Data System (ADS)

    Zahirovic, Sabin; Dietmar Müller, R.; Seton, Maria; Flament, Nicolas

    2015-04-01

    Convection in the Earth's mantle that involves plates at the surfaces gives rise to plate velocities that vary through time and depend on the balance of plate boundary forces, with the present-day providing a snapshot of this ongoing process. However, present-day plate velocities do not capture plate behaviour over geologically representative timeframes and thus cannot be used to evaluate factors limiting plate velocities. Previous studies investigated the effects of continental keels on plate speeds by either using the present-day snapshot or a limited number of reconstructed plate configurations, often leading to conflicting results. For example, an early assumption was that continental keels (especially cratons) were unlikely to impede fast plate motions because India's velocity approached ~20 cm/yr in the Eocene prior to the collision with Eurasia. We employ a modern plate reconstruction approach with evolving global topological plate boundaries for the post-Pangea timeframe (since 200 Ma) to evaluate factors controlling plate velocities. Plate boundary configurations and plate velocities are extracted from the open-source and cross-platform plate reconstruction package GPlates (www.gplates.org) at 1 Myr intervals. For each plate, at each timestep, the area of continental and cratonic lithosphere is calculated to evaluate the effect on plate velocities. Our results support that oceanic plates tend to be 2-3 times faster than plates with large portion of continental plate area, consistent with predictions of numerical models of mantle convection. The fastest plates (~8.5 cm/yr RMS) are dominated by oceanic plate area and high subducting portion of plate perimeter, while the slowest plates (~2.6-2.8 cm/yr RMS) are dominated by continental plate area and bounded by transforms and mid-oceanic ridge segments. Importantly, increasing cratonic fractions (both Proterozoic and Archean lithosphere) significantly impede plate velocities, suggesting that deep continental

  2. Reduced Plating Ignitron

    NASA Technical Reports Server (NTRS)

    Polzin, Kurt A (Inventor); Pearson, J Boise (Inventor)

    2014-01-01

    An ignitron apparatus has an airtight tubular housing having a first sealed end and a second sealed end. An anode is connected at the first sealed end, projecting into the housing, and a recess at the second sealed and forms a well which contains a quantity of liquid gallium or gallium alloy making up the cathode. An ignitor projects through the liquid metal and into the housing. The inner surface of the housing includes at least one plating-reduction structure to prevent electrical shorting of the apparatus caused by plating of the liquid metal.

  3. NICKEL PLATING PROCESS

    DOEpatents

    Hoover, T.B.; Zava, T.E.

    1959-05-12

    A simplified process is presented for plating nickel by the vapor decomposition of nickel carbonyl. In a preferred form of the invention a solid surface is nickel plated by subjecting the surface to contact with a mixture containing by volume approximately 20% nickel carbonyl vapor, 2% hydrogen sulfide and .l% water vapor or 1% oxygen and the remainder carbon dioxide at room temperature until the desired thickness of nickel is obtained. The advantage of this composition over others is that the normally explosive nickel carbonyl is greatly stabilized.

  4. Nuclear reactor alignment plate configuration

    DOEpatents

    Altman, David A; Forsyth, David R; Smith, Richard E; Singleton, Norman R

    2014-01-28

    An alignment plate that is attached to a core barrel of a pressurized water reactor and fits within slots within a top plate of a lower core shroud and upper core plate to maintain lateral alignment of the reactor internals. The alignment plate is connected to the core barrel through two vertically-spaced dowel pins that extend from the outside surface of the core barrel through a reinforcement pad and into corresponding holes in the alignment plate. Additionally, threaded fasteners are inserted around the perimeter of the reinforcement pad and into the alignment plate to further secure the alignment plate to the core barrel. A fillet weld also is deposited around the perimeter of the reinforcement pad. To accomodate thermal growth between the alignment plate and the core barrel, a gap is left above, below and at both sides of one of the dowel pins in the alignment plate holes through with the dowel pins pass.

  5. Growth Plate Injuries

    MedlinePlus

    ... or crushed, the growth plate may close prematurely, forming a bony bridge or “bar.” The risk of ... this publication: James S. Panagis, M.D., M.P.H., NIAMS/NIH; R. Tracy Ballock, M.D., Case ...

  6. The Plate Tectonics Project

    ERIC Educational Resources Information Center

    Hein, Annamae J.

    2011-01-01

    The Plate Tectonics Project is a multiday, inquiry-based unit that facilitates students as self-motivated learners. Reliable Web sites are offered to assist with lessons, and a summative rubric is used to facilitate the holistic nature of the project. After each topic (parts of the Earth, continental drift, etc.) is covered, the students will…

  7. INL HIP Plate Fabrication

    SciTech Connect

    B. H. Park; C. R. Clark; J. F. Jue

    2010-02-01

    This document outlines the process used to bond monolithic fuel plates by Hot Isostatic Pressing (HIP). This method was developed at Idaho National Laboratory (INL) for the Reduced Enrichment for Research and Test Reactors (RERTR) program. These foils have been used in a number of irradiation experiments in support of the United States Global Threat Reduction Initiative (GTRI) program.

  8. Unitary plate electrode

    NASA Technical Reports Server (NTRS)

    Rowlette, John J. (Inventor); Clough, Thomas J. (Inventor); Josefowicz, Jack Y. (Inventor); Sibert, John W. (Inventor)

    1985-01-01

    The unitary electrode (10) comprises a porous sheet (12) of fiberglass the strands (14) of which contain a coating (16) of conductive tin oxide. The lower portion of the sheet contains a layer (18) of resin and the upper layer (20) contains lead dioxide forming a positive active electrode on an electrolyte-impervious layer. The strands (14) form a continuous conduction path through both layers (16, 18). Tin oxide is prevented from reduction by coating the surface of the plate facing the negative electrode with a conductive, impervious layer resistant to reduction such as a thin film (130) of lead or graphite filled resin adhered to the plate with a layer (31) of conductive adhesive. The plate (10) can be formed by casting a molten resin from kettle (60) onto a sheet of glass wool (56) overlying a sheet of lead foil and then applying positive active paste from hopper (64) into the upper layer (68). The plate can also be formed by passing an assembly of a sheet ( 80) of resin, a sheet (86) of sintered glass and a sheet (90) of lead between the nip (92) of heated rollers (93, 95) and then filling lead oxide into the pores (116) of the upper layer (118).

  9. Renewable liquid reflecting zone plate

    DOEpatents

    Toor, Arthur; Ryutov, Dmitri D.

    2003-12-09

    A renewable liquid reflecting zone plate. Electrodes are operatively connected to a dielectric liquid in a circular or other arrangement to produce a reflecting zone plate. A system for renewing the liquid uses a penetrable substrate.

  10. MyPlate Food Guide

    MedlinePlus

    ... follow throughout your life. 2. Fruits Like veggies, fruits contain vitamins, minerals, and fiber. The red section of MyPlate is slightly smaller than the green, but together fruits and veggies should fill half your plate. Whole ...

  11. What Are Growth Plate Injuries?

    MedlinePlus

    ... activities. Other reasons for growth plate injuries are:  Child abuse  Injury from extreme cold (for example, frostbite)  Radiation ( ... problems) treats most growth plate injuries. At other times, the child will see a pediatric orthopaedic surgeon (a doctor ...

  12. What Are Growth Plate Injuries?

    MedlinePlus

    ... activities. Other reasons for growth plate injuries are: Child abuse Injury from extreme cold (for example, frostbite) Radiation ( ... problems) treats most growth plate injuries. At other times, the child will see a pediatric orthopaedic surgeon (a doctor ...

  13. Microchannel plate streak camera

    DOEpatents

    Wang, Ching L.

    1989-01-01

    An improved streak camera in which a microchannel plate electron multiplier is used in place of or in combination with the photocathode used in prior streak cameras. The improved streak camera is far more sensitive to photons (UV to gamma-rays) than the conventional x-ray streak camera which uses a photocathode. The improved streak camera offers gamma-ray detection with high temporal resolution. It also offers low-energy x-ray detection without attenuation inside the cathode. Using the microchannel plate in the improved camera has resulted in a time resolution of about 150 ps, and has provided a sensitivity sufficient for 1000 KeV x-rays.

  14. North American plate dynamics

    NASA Technical Reports Server (NTRS)

    Richardson, Randall M.; Reding, Lynn M.

    1991-01-01

    Deformation within the North American plate in response to various tectonic processes is modeled using an elastic finite element analysis. The tectonic processes considered in the modeling include ridge forces associated with the normal thermal evolution of oceanic lithosphere, shear and normal stresses transmitted across transforms, normal stresses transmitted across convergent boundaries, stresses due to horizontal density contrasts within the continent, and shear tractions applied along the base of the plate. Model stresses are calculated with respect to a lithostatic reference stress state. Shear stresses transmitted across transform boundaries along the San Andreas and Caribbean are small, of the order of 5-10 MPa. Also, compressive stresses of the order of 5-10 MPa transmitted across the major transforms improve the fit to the data. Compressive stresses across convergent margins along the Aleutians and the Middle America trench are important.

  15. Microchannel plate streak camera

    DOEpatents

    Wang, C.L.

    1989-03-21

    An improved streak camera in which a microchannel plate electron multiplier is used in place of or in combination with the photocathode used in prior streak cameras is disclosed. The improved streak camera is far more sensitive to photons (UV to gamma-rays) than the conventional x-ray streak camera which uses a photocathode. The improved streak camera offers gamma-ray detection with high temporal resolution. It also offers low-energy x-ray detection without attenuation inside the cathode. Using the microchannel plate in the improved camera has resulted in a time resolution of about 150 ps, and has provided a sensitivity sufficient for 1,000 KeV x-rays. 3 figs.

  16. Microchannel plate streak camera

    DOEpatents

    Wang, C.L.

    1984-09-28

    An improved streak camera in which a microchannel plate electron multiplier is used in place of or in combination with the photocathode used in prior streak cameras. The improved streak camera is far more sensitive to photons (uv to gamma-rays) than the conventional x-ray streak camera which uses a photocathode. The improved streak camera offers gamma-ray detection with high temporal resolution. It also offers low-energy x-ray detection without attenuation inside the cathode. Using the microchannel plate in the improved camera has resulted in a time resolution of about 150 ps, and has provided a sensitivity sufficient for 1000 keV x-rays.

  17. Bipolar battery plate

    NASA Technical Reports Server (NTRS)

    Rowlette, John J. (Inventor)

    1985-01-01

    A liquid-impermeable plate (10) having throughplate conductivity with essentially zero resistance comprises an insulator sheet (12) having a series of spaced perforations (14) each of which contains a metal element (16) sealingly received into the perforation (14). A low-cost plate can readily be manufactured by punching a thermoplastic sheet (40) such as polypropylene with a punching tool (52), filling the apertures with lead spheres (63) having a diameter smaller than the holes (50) but larger than the thickness of the sheet, sweeping excess spheres (62) off the sheet with a doctor blade (60) and then pressing a heated platen (74) onto the sheet to swage the spheres into a cylindrical shape and melt the surrounding resin to form a liquid-impermeable collar (4) sealing the metal into the sheet.

  18. Plate motion and deformation

    SciTech Connect

    Minster, B.; Prescott, W.; Royden, L.

    1991-02-01

    Our goal is to understand the motions of the plates, the deformation along their boundaries and within their interiors, and the processes that control these tectonic phenomena. In the broadest terms, we must strive to understand the relationships of regional and local deformation to flow in the upper mantle and the rheological, thermal and density structure of the lithosphere. The essential data sets which we require to reach our goal consist of maps of current strain rates at the earth's surface and the distribution of integrated deformation through time as recorded in the geologic record. Our success will depend on the effective synthesis of crustal kinematics with a variety of other geological and geophysical data, within a quantitative theoretical framework describing processes in the earth's interior. Only in this way can we relate the snapshot of current motions and earth structure provided by geodetic and geophysical data with long-term processes operating on the time scales relevant to most geological processes. The wide-spread use of space-based techniques, coupled with traditional geological and geophysical data, promises a revolution in our understanding of the kinematics and dynamics of plate motions over a broad range of spatial and temporal scales and in a variety of geologic settings. The space-based techniques that best address problems in plate motion and deformation are precise space-geodetic positioning -- on land and on the seafloor -- and satellite acquisition of detailed altimetric and remote sensing data in oceanic and continental areas. The overall science objectives for the NASA Solid Earth Science plan for the 1990's, are to Understand the motion and deformation of the lithosphere within and across plate boundaries'', and to understand the dynamics of the mantle, the structure and evolution of the lithosphere, and the landforms that result from local and regional deformation. 57 refs., 7 figs., 2 tabs.

  19. Smov FOS Plate Scale

    NASA Astrophysics Data System (ADS)

    Kinney, Anne

    1994-01-01

    The goal is to measure the precise plate scale and orientation. This will be acheived by performing a raster step and dwell sequence in the 4.3 arcsec aperture. The edges of the aperture should be avoided to prevent vignetting effects. An aperture map is required at each step of the dwell sequence. This test has to be conducted for both the RED and BLUE detectors. We will also determine the offset between the two detectors.

  20. Plated wire memory subsystem

    NASA Technical Reports Server (NTRS)

    Reynolds, L.; Tweed, H.

    1972-01-01

    The work performed entailed the design, development, construction and testing of a 4000 word by 18 bit random access, NDRO plated wire memory for use in conjunction with a spacecraft imput/output unit and central processing unit. The primary design parameters, in order of importance, were high reliability, low power, volume and weight. A single memory unit, referred to as a qualification model, was delivered.

  1. Martian plate tectonics

    NASA Astrophysics Data System (ADS)

    Sleep, N. H.

    1994-03-01

    The northern lowlands of Mars have been produced by plate tectonics. Preexisting old thick highland crust was subducted, while seafloor spreading produced thin lowland crust during late Noachian and Early Hesperian time. In the preferred reconstruction, a breakup margin extended north of Cimmeria Terra between Daedalia Planum and Isidis Planitia where the highland-lowland transition is relatively simple. South dipping subduction occured beneath Arabia Terra and east dipping subduction beneath Tharsis Montes and Tempe Terra. Lineations associated with Gordii Dorsum are attributed to ridge-parallel structures, while Phelegra Montes and Scandia Colles are interpreted as transfer-parallel structures or ridge-fault-fault triple junction tracks. Other than for these few features, there is little topographic roughness in the lowlands. Seafloor spreading, if it occurred, must have been relatively rapid. Quantitative estimates of spreading rate are obtained by considering the physics of seafloor spreading in the lower (approx. 0.4 g) gravity of Mars, the absence of vertical scarps from age differences across fracture zones, and the smooth axial topography. Crustal thickness at a given potential temperature in the mantle source region scales inversely with gravity. Thus, the velocity of the rough-smooth transition for axial topography also scales inversely with gravity. Plate reorganizations where young crust becomes difficult to subduct are another constraint on spreading age. Plate tectonics, if it occurred, dominated the thermal and stress history of the planet. A geochemical implication is that the lower gravity of Mars allows deeper hydrothermal circulation through cracks and hence more hydration of oceanic crust so that more water is easily subducted than on the Earth. Age and structural relationships from photogeology as well as median wavelength gravity anomalies across the now dead breakup and subduction margins are the data most likely to test and modify hypotheses

  2. Elastic plate spallation

    NASA Technical Reports Server (NTRS)

    Oline, L.; Medaglia, J.

    1972-01-01

    The dynamic finite element method was used to investigate elastic stress waves in a plate. Strain displacement and stress strain relations are discussed along with the stiffness and mass matrix. The results of studying point load, and distributed load over small, intermediate, and large radii are reported. The derivation of finite element matrices, and the derivation of lumped and consistent matrices for one dimensional problems with Laplace transfer solutions are included. The computer program JMMSPALL is also included.

  3. Plates with Incompatible Prestrain

    NASA Astrophysics Data System (ADS)

    Bhattacharya, Kaushik; Lewicka, Marta; Schäffner, Mathias

    2016-07-01

    We study effective elastic behavior of the incompatibly prestrained thin plates, where the prestrain is independent of thickness and uniform through the plate's thickness h. We model such plates as three-dimensional elastic bodies with a prescribed pointwise stress-free state characterized by a Riemannian metric G, and seek the limiting behavior as {h to 0}. We first establish that when the energy per volume scales as the second power of h, the resulting {Γ} -limit is a Kirchhoff-type bending theory. We then show the somewhat surprising result that there exist non-immersible metrics G for whom the infimum energy (per volume) scales smaller than h 2. This implies that the minimizing sequence of deformations carries nontrivial residual three-dimensional energy but it has zero bending energy as seen from the limit Kirchhoff theory perspective. Another implication is that other asymptotic scenarios are valid in appropriate smaller scaling regimes of energy. We characterize the metrics G with the above property, showing that the zero bending energy in the Kirchhoff limit occurs if and only if the Riemann curvatures R 1213, R 1223 and R 1212 of G vanish identically. We illustrate our findings with examples; of particular interest is an example where {G_{2 × 2}}, the two-dimensional restriction of G, is flat but the plate still exhibits the energy scaling of the Föppl-von Kármán type. Finally, we apply these results to a model of nematic glass, including a characterization of the condition when the metric is immersible, for {G = Id3 + γ n ⊗ n} given in terms of the inhomogeneous unit director field distribution { n in R^3}.

  4. Origin of Small Tectonic Plates

    NASA Astrophysics Data System (ADS)

    Mallard, C.; Coltice, N.; Seton, M.; Müller, D.; Tackley, P.

    2015-12-01

    The plate tectonic theory allowed to split the Earth surface into 6 (Le Pichon 1968) to 52 tectonic plates (Bird 2003). These plates are separated into two groups: the first of 7 large plates and the second of numerous smaller plates (Morra et al 2013). Previous studies using the reconstruction of the past 200 My, suggest that the size of large plates is driven by mantle flow. But the tools employed are descriptive (Morra et al 2013, Sornette and Pisarenko 2003), hence ignoring forces and physical principles within the lithosphere and the mantle. The processes at the origin of small plates remain unknown. We developed a new approach to explain the plate sizes. We demonstrate that the physics of convection drives it. We applied plate tectonics theory on 3D spherical convection models generating plate-like motions, which give access to a complete survey of data: velocities, viscosity and heat flow. Our data show that (1) the large plates depend on the dominating scale of the convective flow due to the initiation or the shutdown of subductions; (2) the smaller plates are generated thanks to large variability of regional stresses along subduction zone by slab pull and suction influenced by the geometry of trenches. Our results are consistent with the quick reorganizations of back-arc basins occuring synchronously with the modification of subduction zones geometry around the Pacific plate (Sdrolias et al 2004). Hence, we conclude that (1) the decreasing number of small plates in the plate reconstructions back in time is an artifact induced by their short lifetime, that is why they are artificially ignored; (2) the geometry of past trenches is simplified leading to an underestimation of the length of subduction zones.

  5. Plate tectonics conserves angular momentum

    NASA Astrophysics Data System (ADS)

    Bowin, C.

    2009-03-01

    A new combined understanding of plate tectonics, Earth internal structure, and the role of impulse in deformation of the Earth's crust is presented. Plate accelerations and decelerations have been revealed by iterative filtering of the quaternion history for the Euler poles that define absolute plate motion history for the past 68 million years, and provide an unprecedented precision for plate angular rotation variations with time at 2-million year intervals. Stage poles represent the angular rotation of a plate's motion between adjacent Euler poles, and from which the maximum velocity vector for a plate can be determined. The consistent maximum velocity variations, in turn, yield consistent estimates of plate accelerations and decelerations. The fact that the Pacific plate was shown to accelerate and decelerate, implied that conservation of plate tectonic angular momentum must be globally conserved, and that is confirmed by the results shown here (total angular momentum ~1.4 E+27 kgm2s-1). Accordingly, if a plate decelerates, other plates must increase their angular momentums to compensate. In addition, the azimuth of the maximum velocity vectors yields clues as to why the "bend" in the Emperor-Hawaiian seamount trend occurred near 46 Myr. This report summarizes processing results for 12 of the 14 major tectonic plates of the Earth (except for the Juan de Fuca and Philippine plates). Plate accelerations support the contention that plate tectonics is a product of torques that most likely are sustained by the sinking of positive density anomalies due to phase changes in subducted gabbroic lithosphere at depth in the upper lower mantle (above 1200 km depth). The tectonic plates are pulled along by the sinking of these positive mass anomalies, rather than moving at near constant velocity on the crests of convection cells driven by rising heat. These results imply that spreading centers are primarily passive reactive features, and fracture zones (and wedge-shaped sites

  6. Symmetries in laminated composite plates

    NASA Technical Reports Server (NTRS)

    Noor, A. K.

    1976-01-01

    The different types of symmetry exhibited by laminated anisotropic fibrous composite plates are identified and contrasted with the symmetries of isotropic and homogeneous orthotropic plates. The effects of variations in the fiber orientation and the stacking sequence of the layers on the symmetries exhibited by composite plates are discussed. Both the linear and geometrically nonlinear responses of the plates are considered. A simple procedure is presented for exploiting the symmetries in the finite element analysis. Examples are given of square, skew and polygonal plates where use of symmetry concepts can significantly reduce the scope and cost of analysis.

  7. Fuel cell end plate structure

    DOEpatents

    Guthrie, Robin J.; Katz, Murray; Schroll, Craig R.

    1991-04-23

    The end plates (16) of a fuel cell stack (12) are formed of a thin membrane. Pressure plates (20) exert compressive load through insulation layers (22, 26) to the membrane. Electrical contact between the end plates (16) and electrodes (50, 58) is maintained without deleterious making and breaking of electrical contacts during thermal transients. The thin end plate (16) under compressive load will not distort with a temperature difference across its thickness. Pressure plate (20) experiences a low thermal transient because it is insulated from the cell. The impact on the end plate of any slight deflection created in the pressure plate by temperature difference is minimized by the resilient pressure pad, in the form of insulation, therebetween.

  8. Wobble plate engine

    SciTech Connect

    Derderian, H.; Pronovost, J.

    1980-07-01

    A description is given of a conventional Stirling cycle engine of the type characterized by an elongated cylinder having a closed end and an open end, means for applying heat to the exterior of the cylinder to heat gas in the interior of the cylinder at the closed end thereof, a displacer piston mounted for a reciprocation within the closed end of the cylinder and a power piston axially aligned with the displacer piston and mounted for coaxial reciprocation between the displacer piston and the open end of the cylinder, the reciprocation of the displacer piston leading the corresponding stroke of the power piston by a predetermined phase angle, the improved means for properly phasing the reciprocation of the two pistons and for converting the reciprocation of the power piston into rotation of an output shaft which is parallel to the axis of reciprocation comprising: a supporting frame; an output shaft mounted on said frame for rotation about a first axis which is parallel to the axis of reciprocation of the two pistons, said shaft having an inclined cylindrical bearing surface the axis of which intersects said first axis at an acute angle; gimbal means pivotally mounted on said supporting frame for oscillation about a second axis perpendicular to and intersecting first axis; a wobble plate pivotally mounted on a third axis within said gimbal means for oscillation with said gimbal means and for further oscillation about said third axis which is mutually perpendicular to and intersecting said first and second axes, said wobble plate being rotatably mounted on said inclined cylindrical bearing surface in a plane which is perpendicular to said axis of said bearing surface whereby said output shaft can rotate about said first axis as said wobble plate oscillates about said second and third axes.

  9. Shuttle plate braiding machine

    NASA Technical Reports Server (NTRS)

    Huey, Jr., Cecil O. (Inventor)

    1994-01-01

    A method and apparatus for moving yarn in a selected pattern to form a braided article. The apparatus includes a segmented grid of stationary support elements and a plurality of shuttles configured to carry yarn. The shuttles are supported for movement on the grid assembly and each shuttle includes a retractable plunger for engaging a reciprocating shuttle plate that moves below the grid assembly. Such engagement at selected times causes the shuttles to move about the grid assembly in a selected pattern to form a braided article of a particular geometry.

  10. Reduced hydrogen cadmium plating

    SciTech Connect

    Hoeller, T.; Ross, L. ); Varma, R. ); Agarwala, V.S. )

    1991-01-01

    This paper demonstrates the advantages of using a periodic reverse pulse plating method, incorporating a fast cathodic pulse which is separated from the subsequent anodic/cathodic pulses by a long rest period in producing silvery cadmium coatings on steel from aqueous fluoroborate electrolyte. Also, the deposition obtained by combination of pulse currents and turbulent electrolyte flow system (forced convection of electrolyte, Re {approximately} 20-25,000) result in a near hydrogen-free electrodeposition of fine- grained cadmium. This is confirmed by the determination of diffusible hydrogen by the electrochemical (Barnach Electrode) method.

  11. Plated wire memory subsystem

    NASA Technical Reports Server (NTRS)

    Carpenter, K. H.

    1974-01-01

    The design, construction, and test history of a 4096 word by 18 bit random access NDRO Plated Wire Memory for use in conjunction with a spacecraft input/output and central processing unit is reported. A technical and functional description is given along with diagrams illustrating layout and systems operation. Test data is shown on the procedures and results of system level and memory stack testing, and hybrid circuit screening. A comparison of the most significant physical and performance characteristics of the memory unit versus the specified requirements is also included.

  12. Ultrafast microchannel plate photomultipliers.

    PubMed

    Kume, H; Koyama, K; Nakatsugawa, K; Suzuki, S; Fatlowitz, D

    1988-03-15

    Performance characteristics of several new types of photomultiplier tubes (PMT) with microchannel plates (MCP) are presented in this paper. They are the MCP-PMT with 6-microm diam channels, MCP-PMT with an S-l photocathode, and MCP-PMT with multi (discrete) anode and gatable MCP-PMT. Important requirements of an optical detector for picosecond lasers, fluorescence measurements, and material analysis are low light detectability, ultrafast time response, and versatile operation including modulation. The basic configuration, characteristics, and practical results of these detectors are described. PMID:20531532

  13. Tectonics of the Easter plate

    NASA Technical Reports Server (NTRS)

    Engeln, J. F.; Stein, S.

    1984-01-01

    A new model for the Easter plate is presented in which rift propagation has resulted in the formation of a rigid plate between the propagating and dying ridges. The distribution of earthquakes, eleven new focal mechanisms, and existing bathymetric and magnetic data are used to describe the tectonics of this area. Both the Easter-Nazca and Easter-Pacific Euler poles are sufficiently close to the Easter plate to cause rapid changes in rates and directions of motion along the boundaries. The east and west boundaries are propagating and dying ridges; the southwest boundary is a slow-spreading ridge and the northern boundary is a complex zone of convergent and transform motion. The Easter plate may reflect the tectonics of rift propagation on a large scale, where rigid plate tectonics requires boundary reorientation. Simple schematic models to illustrate the general features and processes which occur at plates resulting from large-scale rift propagation are used.

  14. Localised Plate Motion on Venus

    NASA Astrophysics Data System (ADS)

    Ghail, R. C.

    1996-03-01

    The volcanic and tectonic features observed in Dali Vinculum, Parga Vinculum and Imdr Regio are concentrated at long, narrow, curvilinear zones, with relatively minor volcanism and tectonism between these zones. These zones, whilst more diffuse than terrestrial plate boundaries, nevertheless define the margins of tectonic plates. In contrast to Earth, however, it appears that venusian plates are neither created nor destroyed by lateral motion. Rather, plates are thinned and intruded at vincula plate boundaries, vertically accreted by small-scale intra-plate (planitia) volcanism and perhaps destroyed by delamination of thickened crust in tesserae and montane regions such as Thetis Regio and Ishtar Terra. The diversity in age both between and within these three areas together with the evidence for infrequent, small scale resurfacing in the planitiae are difficult to reconcile with a non-uniformitarian geological process.

  15. Multiple plate hydrostatic viscous damper

    SciTech Connect

    Ludwig, L.P.

    1981-02-01

    A device for damping radial motion of a rotating shaft is described. The damper comprises a series of spaced plates extending in a radial direction. A hydraulic piston is utilized to place a load in these plates. Each annular plate is provided with a suitable hydrostatic bearing geometry on at least one of its faces. This structure provides a high degree of dampening in a rotor case system of turbomachinery in general. The damper is particularly useful in gas turbine engines.

  16. Multiple plate hydrostatic viscous damper

    NASA Technical Reports Server (NTRS)

    Ludwig, L. P. (Inventor)

    1981-01-01

    A device for damping radial motion of a rotating shaft is described. The damper comprises a series of spaced plates extending in a radial direction. A hydraulic piston is utilized to place a load in these plates. Each annular plate is provided with a suitable hydrostatic bearing geometry on at least one of its faces. This structure provides a high degree of dampening in a rotor case system of turbomachinery in general. The damper is particularly useful in gas turbine engines.

  17. Channel plate for DNA sequencing

    DOEpatents

    Douthart, R.J.; Crowell, S.L.

    1998-01-13

    This invention is a channel plate that facilitates data compaction in DNA sequencing. The channel plate has a length, a width and a thickness, and further has a plurality of channels that are parallel. Each channel has a depth partially through the thickness of the channel plate. Additionally an interface edge permits electrical communication across an interface through a buffer to a deposition membrane surface. 15 figs.

  18. Ion plating for the future

    NASA Technical Reports Server (NTRS)

    Spalvins, T.

    1981-01-01

    The ion plating techniques are classified relative to the instrumental set up, evaporation media, and mode of transport. A distinction is drawn between the low vacuum (plasma) and high vacuum (ion beam) techniques. Ion plating technology is discussed at the fundamental and industrial level. At the fundamental level, the capabilities and limitations of the plasma (evaporant flux) and film characteristics are evaluated. And on the industrial level, the performance and potential uses of ion plated films are discussed.

  19. Channel plate for DNA sequencing

    DOEpatents

    Douthart, Richard J.; Crowell, Shannon L.

    1998-01-01

    This invention is a channel plate that facilitates data compaction in DNA sequencing. The channel plate has a length, a width and a thickness, and further has a plurality of channels that are parallel. Each channel has a depth partially through the thickness of the channel plate. Additionally an interface edge permits electrical communication across an interface through a buffer to a deposition membrane surface.

  20. Carbon-assisted flyer plates

    DOEpatents

    Stahl, David B.; Paisley, Dennis L.

    1994-01-01

    A laser driven flyer plate utilizing an optical fiber connected to a laser. The end of the optical fiber has a layer of carbon and a metal layer deposited onto it. The carbon layer provides the laser induced plasma which is superior to the plasma produced from most metals. The carbon layer plasma is capable of providing a flatter flyer plate, converting more of the laser energy to driving plasma, promoting a higher flyer plate acceleration, and providing a more uniform pulse behind the plate. In another embodiment, the laser is in optical communication with a substrate onto which a layer of carbon and a layer of metal have been deposited.

  1. True Shear Parallel Plate Viscometer

    NASA Technical Reports Server (NTRS)

    Ethridge, Edwin; Kaukler, William

    2010-01-01

    This viscometer (which can also be used as a rheometer) is designed for use with liquids over a large temperature range. The device consists of horizontally disposed, similarly sized, parallel plates with a precisely known gap. The lower plate is driven laterally with a motor to apply shear to the liquid in the gap. The upper plate is freely suspended from a double-arm pendulum with a sufficiently long radius to reduce height variations during the swing to negligible levels. A sensitive load cell measures the shear force applied by the liquid to the upper plate. Viscosity is measured by taking the ratio of shear stress to shear rate.

  2. Glass-bead peen plating

    NASA Technical Reports Server (NTRS)

    Graves, J. R.

    1974-01-01

    Peen plating of aluminum, copper, and nickel powders was investigated. Only aluminum was plated successfully within the range of peen plating conditions studied. Optimum plating conditions for aluminum were found to be: (1) bead/powder mixture containing 25 to 35% powder by weight, (2) peening intensity of 0.007A as measured by Almen strip, and (3) glass impact bead diameter of at least 297 microns (0.0117 inches) for depositing-100 mesh aluminum powder. No extensive cleaning or substrate preparation is required beyond removing loose dirt or heavy oil.

  3. Laser-driven flyer plate

    SciTech Connect

    Paisley, D.L.

    1991-09-10

    Disclosed is an apparatus for producing high velocity flyer plates involving placing a layer of dielectric material between a first metal foil and a second metal foil. With laser irradiation through an optical substrate, the first metal foil forms a plasma in the area of the irradiation, between the substrate and the solid portion of the first metal foil. When the pressure between the substrate and the foil reaches the stress limit of the dielectric, the dielectric will break away and launch the flyer plate out of the second metal foil. The mass of the flyer plate is controlled, as no portion of the flyer plate is transformed into a plasma. 2 figures.

  4. Laser-driven flyer plate

    DOEpatents

    Paisley, Dennis L.

    1991-01-01

    Apparatus for producing high velocity flyer plates involving placing a layer of dielectric material between a first metal foil and a second metal foil. With laser irradiation through an optical substrate, the first metal foil forms a plasma in the area of the irradiation, between the substrate and the solid portion of the first metal foil. When the pressure between the substrate and the foil reaches the stress limit of the dielectric, the dielectric will break away and launch the flyer plate out of the second metal foil. The mass of the flyer plate is controlled, as no portion of the flyer plate is transformed into a plasma.

  5. Scintillator plate calorimetry

    SciTech Connect

    Price, L.E.

    1990-01-01

    Calorimetry using scintillator plates or tiles alternated with sheets of (usually heavy) passive absorber has been proven over multiple generations of collider detectors. Recent detectors including UA1, CDF, and ZEUS have shown good results from such calorimeters. The advantages offered by scintillator calorimetry for the SSC environment, in particular, are speed (<10 nsec), excellent energy resolution, low noise, and ease of achieving compensation and hence linearity. On the negative side of the ledger can be placed the historical sensitivity of plastic scintillators to radiation damage, the possibility of nonuniform response because of light attenuation, and the presence of cracks for light collection via wavelength shifting plastic (traditionally in sheet form). This approach to calorimetry is being investigated for SSC use by a collaboration of Ames Laboratory/Iowa State University, Argonne National Laboratory, Bicron Corporation, Florida State University, Louisiana State University, University of Mississippi, Oak Ridge National Laboratory, Virginia Polytechnic Institute and State University, Westinghouse Electric Corporation, and University of Wisconsin.

  6. 10. DETAIL OF BUILDER'S PLATE AT NORTH PORTAL. PLATE READS: ...

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

    10. DETAIL OF BUILDER'S PLATE AT NORTH PORTAL. PLATE READS: 1889, BUILT BY THE BERLIN IRON BRIDGE CO. EAST BERLIN CONN. DOUGLAS & JARVIS PAT. APT. 16, 1878, AP'L 17, 1885. A.P. FORESMAN, WM. S. STARR, T.J. STREBEIGH, COMMISSIONERS. - Pine Creek Bridge, River Road spanning Pine Creek, Jersey Shore, Lycoming County, PA

  7. Plate tectonics conserves angular momentum

    NASA Astrophysics Data System (ADS)

    Bowin, C.

    2010-03-01

    A new combined understanding of plate tectonics, Earth internal structure, and the role of impulse in deformation of the Earth's crust is presented. Plate accelerations and decelerations have been revealed by iterative filtering of the quaternion history for the Euler poles that define absolute plate motion history for the past 68 million years, and provide an unprecedented precision for plate angular rotation variations with time at 2-million year intervals. Stage poles represent the angular rotation of a plate's motion between adjacent Euler poles, and from which the maximum velocity vector for a plate can be determined. The consistent maximum velocity variations, in turn, yield consistent estimates of plate accelerations and decelerations. The fact that the Pacific plate was shown to accelerate and decelerate, implied that conservation of plate tectonic angular momentum must be globally conserved, and that is confirmed by the results shown here (total angular momentum ~1.4+27 kg m2 s-1). Accordingly, if a plate decelerates, other plates must increase their angular momentums to compensate. In addition, the azimuth of the maximum velocity vectors yields clues as to why the "bend" in the Emperor-Hawaiian seamount trend occurred near 46 Myr. This report summarizes processing results for 12 of the 14 major tectonic plates of the Earth (except for the Juan de Fuca and Philippine plates). Plate accelerations support the contention that plate tectonics is a product of torques that most likely are sustained by the sinking of positive density anomalies revealed by geoid anomalies of the degree 4-10 packet of the Earth's spherical harmonic coefficients. These linear positive geoid anomalies underlie plate subduction zones and are presumed due to phase changes in subducted gabbroic lithosphere at depth in the upper lower mantle (above 1200 km depth). The tectonic plates are pulled along by the sinking of these positive mass anomalies, rather than moving at near constant

  8. Plate tectonics, damage and inheritance.

    PubMed

    Bercovici, David; Ricard, Yanick

    2014-04-24

    The initiation of plate tectonics on Earth is a critical event in our planet's history. The time lag between the first proto-subduction (about 4 billion years ago) and global tectonics (approximately 3 billion years ago) suggests that plates and plate boundaries became widespread over a period of 1 billion years. The reason for this time lag is unknown but fundamental to understanding the origin of plate tectonics. Here we suggest that when sufficient lithospheric damage (which promotes shear localization and long-lived weak zones) combines with transient mantle flow and migrating proto-subduction, it leads to the accumulation of weak plate boundaries and eventually to fully formed tectonic plates driven by subduction alone. We simulate this process using a grain evolution and damage mechanism with a composite rheology (which is compatible with field and laboratory observations of polycrystalline rocks), coupled to an idealized model of pressure-driven lithospheric flow in which a low-pressure zone is equivalent to the suction of convective downwellings. In the simplest case, for Earth-like conditions, a few successive rotations of the driving pressure field yield relic damaged weak zones that are inherited by the lithospheric flow to form a nearly perfect plate, with passive spreading and strike-slip margins that persist and localize further, even though flow is driven only by subduction. But for hotter surface conditions, such as those on Venus, accumulation and inheritance of damage is negligible; hence only subduction zones survive and plate tectonics does not spread, which corresponds to observations. After plates have developed, continued changes in driving forces, combined with inherited damage and weak zones, promote increased tectonic complexity, such as oblique subduction, strike-slip boundaries that are subparallel to plate motion, and spalling of minor plates. PMID:24717430

  9. Stepped conical zone plate antenna

    NASA Astrophysics Data System (ADS)

    Wiltse, James C.

    2001-07-01

    The Fresnel zone plate lens was invented and developed for optical frequencies. However, fabrication difficulties at the short optical wavelengths have prevented obtain good efficiencies. At longer microwave or millimeter-wavelengths fabrication is easier and phase correcting zone plate antennas have been used to obtain good efficiencies. This paper describes a new type of phase correcting zone plate having even better efficiency, namely a diffraction efficiency of 99 percent compared to a true lens, and an overall efficiency much better than a true lens. For the usual zone plate antenna employed at microwave or millimeter wavelengths, path length adjustment is accomplished by cutting different depths in a dielectric plate or by using two or more dielectrics having different dielectric constants. The new design uses a tilted cut in a dielectric plate, which more accurately matches the shape of a true lens and produces much lower phase error. The construction is still near and can be made for example, by a milling machine with a tilted bit. For a circular zone plate, the lens is a stepped conical or tapered shape. Because the phase steps are small, the far-field antenna pattern is excellent and sidelobe-levels are very low. Analysis of typical configurations will be given, showing that phase errors are small, lower than those for an eighth-wave corrected phase zone plate.

  10. ChooseMyPlate.gov

    MedlinePlus

    ... Day You don’t have to be an Olympic athlete to be active. Taking the stairs instead of the elevator, mowing the lawn, and gardening count too! TWITTER FEED 2 days ChooseMyPlate.gov @MyPlate Make family dinner more fun with a game or activity. Challenge kids to solve a riddle ...

  11. Micro-channel plate detector

    DOEpatents

    Elam, Jeffrey W.; Lee, Seon W.; Wang, Hsien -Hau; Pellin, Michael J.; Byrum, Karen; Frisch, Henry J.

    2015-09-22

    A method and system for providing a micro-channel plate detector. An anodized aluminum oxide membrane is provided and includes a plurality of nanopores which have an Al coating and a thin layer of an emissive oxide material responsive to incident radiation, thereby providing a plurality of radiation sensitive channels for the micro-channel plate detector.

  12. Aseptic Laboratory Techniques: Plating Methods

    PubMed Central

    Sanders, Erin R.

    2012-01-01

    Microorganisms are present on all inanimate surfaces creating ubiquitous sources of possible contamination in the laboratory. Experimental success relies on the ability of a scientist to sterilize work surfaces and equipment as well as prevent contact of sterile instruments and solutions with non-sterile surfaces. Here we present the steps for several plating methods routinely used in the laboratory to isolate, propagate, or enumerate microorganisms such as bacteria and phage. All five methods incorporate aseptic technique, or procedures that maintain the sterility of experimental materials. Procedures described include (1) streak-plating bacterial cultures to isolate single colonies, (2) pour-plating and (3) spread-plating to enumerate viable bacterial colonies, (4) soft agar overlays to isolate phage and enumerate plaques, and (5) replica-plating to transfer cells from one plate to another in an identical spatial pattern. These procedures can be performed at the laboratory bench, provided they involve non-pathogenic strains of microorganisms (Biosafety Level 1, BSL-1). If working with BSL-2 organisms, then these manipulations must take place in a biosafety cabinet. Consult the most current edition of the Biosafety in Microbiological and Biomedical Laboratories (BMBL) as well as Material Safety Data Sheets (MSDS) for Infectious Substances to determine the biohazard classification as well as the safety precautions and containment facilities required for the microorganism in question. Bacterial strains and phage stocks can be obtained from research investigators, companies, and collections maintained by particular organizations such as the American Type Culture Collection (ATCC). It is recommended that non-pathogenic strains be used when learning the various plating methods. By following the procedures described in this protocol, students should be able to: ● Perform plating procedures without contaminating media. ● Isolate single bacterial colonies by the

  13. Present-day plate motions

    NASA Technical Reports Server (NTRS)

    Minster, J. B.; Jordan, T. H.

    1977-01-01

    A data set comprising 110 spreading rates, 78 transform fault azimuths and 142 earthquake slip vectors was inverted to yield a new instantaneous plate motion model, designated RM2. The mean averaging interval for the relative motion data was reduced to less than 3 My. A detailed comparison of RM2 with angular velocity vectors which best fit the data along individual plate boundaries indicates that RM2 performs close to optimally in most regions, with several notable exceptions. On the other hand, a previous estimate (RM1) failed to satisfy an extensive set of new data collected in the South Atlantic Ocean. It is shown that RM1 incorrectly predicts the plate kinematics in the South Atlantic because the presently available data are inconsistent with the plate geometry assumed in deriving RM1. It is demonstrated that this inconsistency can be remedied by postulating the existence of internal deformation with the Indian plate, although alternate explanations are possible.

  14. Impact damage of composite plates

    NASA Technical Reports Server (NTRS)

    Lal, K. M.; Goglia, G. L.

    1983-01-01

    A simple model to study low velocity transverse impact of thin plates made of fiber-reinforced composite material, in particular T300/5208 graphite-epoxy was discussed. This model predicts the coefficient of restitution, which is a measure of the energy absorbed by the target during an impact event. The model is constructed on the assumption that the plate is inextensible in the fiber direction and that the material is incompressible in the z-direction. Such a plate essentially deforms by shear, hence this model neglects bending deformations of the plate. The coefficient of restitution is predicted to increase with large interlaminar shear strength and low transverse shear modulus of the laminate. Predictions are compared with the test results of impacted circular and rectangular clamped plates. Experimentally measured values of the coefficient of restitution are found to agree with the predicted values within a reasonable error.

  15. SAMI Automated Plug Plate Configuration

    NASA Astrophysics Data System (ADS)

    Lorente, N. P. F.; Farrell, T.; Goodwin, M.

    2013-10-01

    The Sydney-AAO Multi-object Integral field spectrograph (SAMI) is a prototype wide-field system at the Anglo-Australian Telescope (AAT) which uses a plug-plate to mount its 13×61-core imaging fibre bundles (hexabundles) in the optical path at the telescope's prime focus. In this paper we describe the process of determining the positions of the plug-plate holes, where plates contain three or more stacked observation configurations. The process, which up until now has involved several separate processes and has required significant manual configuration and checking, is now being automated to increase efficiency and reduce error. This is carried out by means of a thin Java controller layer which drives the configuration cycle. This layer controls the user interface and the C++ algorithm layer where the plate configuration and optimisation is carried out. Additionally, through the Aladin display package, it provides visualisation and facilitates user verification of the resulting plates.

  16. Statistical tests of additional plate boundaries from plate motion inversions

    NASA Technical Reports Server (NTRS)

    Stein, S.; Gordon, R. G.

    1984-01-01

    The application of the F-ratio test, a standard statistical technique, to the results of relative plate motion inversions has been investigated. The method tests whether the improvement in fit of the model to the data resulting from the addition of another plate to the model is greater than that expected purely by chance. This approach appears to be useful in determining whether additional plate boundaries are justified. Previous results have been confirmed favoring separate North American and South American plates with a boundary located beween 30 N and the equator. Using Chase's global relative motion data, it is shown that in addition to separate West African and Somalian plates, separate West Indian and Australian plates, with a best-fitting boundary between 70 E and 90 E, can be resolved. These results are generally consistent with the observation that the Indian plate's internal deformation extends somewhat westward of the Ninetyeast Ridge. The relative motion pole is similar to Minster and Jordan's and predicts the NW-SE compression observed in earthquake mechanisms near the Ninetyeast Ridge.

  17. Sub-Plate Overlap Code Documentation

    NASA Technical Reports Server (NTRS)

    Taff, L. G.; Bucciarelli, B.; Zarate, N.

    1997-01-01

    An expansion of the plate overlap method of astrometric data reduction to a single plate has been proposed and successfully tested. Each plate is (artificially) divided into sub-plates which can then be overlapped. This reduces the area of a 'plate' over which a plate model needs to accurately represent the relationship between measured coordinates and standard coordinates. Application is made to non-astrographic plates such as Schmidt plates and to wide-field astrographic plates. Indeed, the method is completely general and can be applied to any type of recording media.

  18. Highly curved microchannel plates

    NASA Technical Reports Server (NTRS)

    Siegmund, O. H. W.; Cully, S.; Warren, J.; Gaines, G. A.; Priedhorsky, W.; Bloch, J.

    1990-01-01

    Several spherically curved microchannel plate (MCP) stack configurations were studied as part of an ongoing astrophysical detector development program, and as part of the development of the ALEXIS satellite payload. MCP pairs with surface radii of curvature as small as 7 cm, and diameters up to 46 mm have been evaluated. The experiments show that the gain (greater than 1.5 x 10 exp 7) and background characteristics (about 0.5 events/sq cm per sec) of highly curved MCP stacks are in general equivalent to the performance achieved with flat MCP stacks of similar configuration. However, gain variations across the curved MCP's due to variations in the channel length to diameter ratio are observed. The overall pulse height distribution of a highly curved surface MCP stack (greater than 50 percent FWHM) is thus broader than its flat counterpart (less than 30 percent). Preconditioning of curved MCP stacks gives comparable results to flat MCP stacks, but it also decreases the overall gain variations. Flat fields of curved MCP stacks have the same general characteristics as flat MCP stacks.

  19. Balanced Orifice Plate

    NASA Technical Reports Server (NTRS)

    Kelley, Anthony R. (Inventor); Buskirk, Paul D. (Inventor)

    2006-01-01

    An orifice plate for use in a conduit through which fluid flows is defined by a central circular region having a radius R, and a ring-shaped region surrounding the central circular region. The ring-shaped region has holes formed therethrough with those holes centered at each radius R thereof satisfying a relationship A(sub R)=al(X(sub R)V(sub R)(sup b)) where A(sub R) is a sum of areas of those holes having centers at radius R, X(sub R) is a flow coefficient at radius R, V(sub R) is a velocity of the fluid that is to flow through the conduit at radius R, b is a constant selected to make at least one process variable (associated with the fluid that is to flow through the conduit) approximately equal at each radius R, and a is a constant that is equal to (X(sub R)A(sub R)V(sub R)(sup b)) at each radius R.

  20. Mantle convection with plates and mobile, faulted plate margins.

    PubMed

    Zhong, S; Gurnis, M

    1995-02-10

    A finite-element formulation of faults has been incorporated into time-dependent models of mantle convection with realistic rheology, continents, and phase changes. Realistic tectonic plates naturally form with self-consistent coupling between plate and mantle dynamics. After the initiation of subduction, trenches rapidly roll back with subducted slabs temporarily laid out along the base of the transition zone. After the slabs have penetrated into the lower mantle, the velocity of trench migration decreases markedly. The inhibition of slab penetration into the lower mantle by the 670-kilometer phase change is greatly reduced in these models as compared to models without tectonic plates. PMID:17813909

  1. The Golosyiv plate archive digitisation

    NASA Astrophysics Data System (ADS)

    Sergeeva, T. P.; Sergeev, A. V.; Pakuliak, L. K.; Yatsenko, A. I.

    2007-08-01

    The plate archive of the Main Astronomical Observatory of the National Academy of Sciences of Ukraine (Golosyiv, Kyiv) includes about 85 000 plates which have been taken in various observational projects during 1950-2005. Among them are about 25 000 of direct northern sky area plates and more than 600 000 plates containing stellar, planetary and active solar formations spectra. Direct plates have a limiting magnitude of 14.0-16.0 mag. Since 2002 we have been organising the storage, safeguarding, cataloguing and digitization of the plate archive. The very initial task was to create the automated system for detection of astronomical objects and phenomena, search of optical counterparts in the directions of gamma-ray bursts, research of long period, flare and other variable stars, search and rediscovery of asteroids, comets and other Solar System bodies to improve the elements of their orbits, informational support of CCD observations and space projects, etc. To provide higher efficiency of this work we have prepared computer readable catalogues and database for 250 000 direct wide field plates. Now the catalogues have been adapted to Wide Field Plate Database (WFPDB) format and integrated into this world database. The next step will be adaptation of our catalogues, database and images to standards of the IVOA. Some magnitude and positional accuracy estimations for Golosyiv archive plates have been done. The photometric characteristics of the images of NGC 6913 cluster stars on two plates of the Golosyiv's double wide angle astrograph have been determined. Very good conformity of the photometric characteristics obtained with external accuracies of 0.13 and 0.15 mag. has been found. The investigation of positional accuracy have been made with A3± format fixed bed scanner (Microtek ScanMaker 9800XL TMA). It shows that the scanner has non-detectable systematic errors on the X-axis, and errors of ± 15 μm on the Y-axis. The final positional errors are about ± 2 μm (

  2. Difficulties encountered removing locked plates

    PubMed Central

    Raja, S; Imbuldeniya, AM; S, Garg; Groom, G

    2012-01-01

    INTRODUCTION Locked plates are commonly used to obtain fixation in periarticular and comminuted fractures. Their use has also gained popularity in repairing fractures in osteoporotic bone. These plates provide stable fixation and promote biological healing. Over the last 3 years, we have used over 150 locked plates with varying success to fix periarticular fractures involving mainly the knee and ankle. In this study, we report our clinical experience and the difficulties encountered when removing locked plates in adult patients with a variety of indications including implant failure, infection, non-union and a palpable symptomatic implant. METHODS A retrospective analysis was performed of patients enrolled prospectively into a database. Included in the study were 36 consecutive adult patients who each underwent the procedure of locked plate removal in a single inner city level 1 trauma centre. Data collected included primary indication for fixation, indication for implant removal, time of the implant in situ, grade of operating surgeon and difficulties encountered during the procedure. RESULTS Implant removal was associated with a complication rate of 47%. The major problems encountered were difficulty in removing the locked screws and the implant itself. A total of ten cold welded screws were found in eight cases. Removal was facilitated by high speed metal cutting burrs and screw removal sets in all but one case, where a decision was made to leave the plate in situ. CONCLUSIONS The majority of studies investigating implant removal and problems encountered in doing so report a relatively high complication rate. With the advent of locking plates and their growing popularity, difficulties are now being seen intra-operatively when removing them. There is a paucity of data, however, specifically directed at locking plate removal. We recommend that surgeons should be aware of the potential complications while removing locked plates. Fluoroscopic control and all

  3. High loading uranium fuel plate

    DOEpatents

    Wiencek, Thomas C.; Domagala, Robert F.; Thresh, Henry R.

    1990-01-01

    Two embodiments of a high uranium fuel plate are disclosed which contain a meat comprising structured uranium compound confined between a pair of diffusion bonded ductile metal cladding plates uniformly covering the meat, the meat having a uniform high fuel loading comprising a content of uranium compound greater than about 45 Vol. % at a porosity not greater than about 10 Vol. %. In a first embodiment, the meat is a plurality of parallel wires of uranium compound. In a second embodiment, the meat is a dispersion compact containing uranium compound. The fuel plates are fabricated by a hot isostatic pressing process.

  4. Plating on stainless steel alloys

    SciTech Connect

    Dini, J.W.; Johnson, H.R.

    1981-09-11

    Quantitative adhesion data are presented for a variety of electroplated stainless steel type alloys. Results show that excellent adhesion can be obtained by using a Wood's nickel strike or a sulfamate nickel strike prior to final plating. Specimens plated after Wood's nickel striking failed in the deposit rather than at the interface between the substrate and the coating. Flyer plate quantitative tests showed that use of anodic treatment in sulfuric acid prior to Wood's nickel striking even further improved adhesion. In contrast activation of stainless steels by immersion or cathodic treatment in hydrochloric acid resulted in very reduced bond strengths with failure always occurring at the interface between the coating and substrate.

  5. The multigap resistive plate chamber

    SciTech Connect

    Zeballos, E. Cerron; Crotty, I.; Hatzifotiadou, D.; Valverde, J. Lamas; Neupane, S.; Williams, M. C. S.; Zichichi, A.

    2015-02-03

    The paper describes the multigap resistive plate chamber (RPC). This is a variant of the wide gap RPC. However it has much improved time resolution, while keeping all the other advantages of the wide gap RPC design.

  6. Quaternions as astrometric plate constants

    NASA Technical Reports Server (NTRS)

    Jefferys, William H.

    1987-01-01

    A new method for solving problems in relative astrometry is proposed. In it, the relationship between the measured quantities and the components of the position vector of a star is modeled using quaternions, in effect replacing the plate constants of a standard four-plate-constant solution with the four components of a quaternion. The method allows a direct solution for the position vectors of the stars, and hence for the equatorial coordinates. Distortions, magnitude, and color effects are readily incorporated into the formalism, and the method is directly applicable to overlapping-plate problems. The advantages of the method include the simplicity of the resulting equations, their freedom from singularities, and the fact that trigonometric functions and tangential point transformations are not needed to model the plate material. A global solution over the entire sky is possible.

  7. Carbon-assisted flyer plates

    DOEpatents

    Stahl, D.B.; Paisley, D.L.

    1994-04-12

    A laser driven flyer plate is described utilizing an optical fiber connected to a laser. The end of the optical fiber has a layer of carbon and a metal layer deposited onto it. The carbon layer provides the laser induced plasma which is superior to the plasma produced from most metals. The carbon layer plasma is capable of providing a flatter flyer plate, converting more of the laser energy to driving plasma, promoting a higher flyer plate acceleration, and providing a more uniform pulse behind the plate. In another embodiment, the laser is in optical communication with a substrate onto which a layer of carbon and a layer of metal have been deposited. 2 figures.

  8. Pulse plating of nickel deposits

    SciTech Connect

    Stimetz, C.J.; Stevenson, M.F.

    1980-02-01

    Pulse plated and conventional nickel deposits have been compared for differences in morphology, mechanical properties, and microstructure. The deposits were obtained from nickel sulfamate, nickel chloride, and Watts nickel plating solutions. No significant differences were found in the direct and pulse current deposits from the sulfamate and chloride solutions; however, significant differences in microstructure, yield strength, and microhardness were observed in deposits from the Watts nickel solution.

  9. Impact on multilayered composite plates

    NASA Technical Reports Server (NTRS)

    Kim, B. S.; Moon, F. C.

    1977-01-01

    Stress wave propagation in a multilayer composite plate due to impact was examined by means of the anisotropic elasticity theory. The plate was modelled as a number of identical anisotropic layers and the approximate plate theory of Mindlin was then applied to each layer to obtain a set of difference-differential equations of motion. Dispersion relations for harmonic waves and correction factors were found. The governing equations were reduced to difference equations via integral transforms. With given impact boundary conditions these equations were solved for an arbitrary number of layers in the plate and the transient propagation of waves was calculated by means of a Fast Fourier Transform algorithm. The multilayered plate problem was extended to examine the effect of damping layers present between two elastic layers. A reduction of the interlaminar normal stress was significant when the thickness of damping layer was increased but the effect was mostly due to the softness of the damping layer. Finally, the problem of a composite plate with a crack on the interlaminar boundary was formulated.

  10. How mantle slabs drive plate tectonics.

    PubMed

    Conrad, Clinton P; Lithgow-Bertelloni, Carolina

    2002-10-01

    The gravitational pull of subducted slabs is thought to drive the motions of Earth's tectonic plates, but the coupling between slabs and plates is not well established. If a slab is mechanically attached to a subducting plate, it can exert a direct pull on the plate. Alternatively, a detached slab may drive a plate by exciting flow in the mantle that exerts a shear traction on the base of the plate. From the geologic history of subduction, we estimated the relative importance of "pull" versus "suction" for the present-day plates. Observed plate motions are best predicted if slabs in the upper mantle are attached to plates and generate slab pull forces that account for about half of the total driving force on plates. Slabs in the lower mantle are supported by viscous mantle forces and drive plates through slab suction. PMID:12364804

  11. Plate mode velocities in graphite/epoxy plates

    NASA Technical Reports Server (NTRS)

    Prosser, W. H.; Gorman, M. R.

    1994-01-01

    Measurements of the velocities of the extensional and flexural plate modes were made along three directions of propagation in four graphite/epoxy composite plates. The acoustic signals were generated by simulated acoustic emission events (pencil lead breaks or Hsu-Neilson sources) and detected by by broadband ultrasonic transducers. The first arrival of the extensional plate mode, which is nondispersive at low frequencies, was measured at a number of different distances from the source along the propagation direction of interest. The velocity was determined by plotting the distance versus arrival time and computing its slope. Because of the large dispersion of the flexural mode, a Fourier phase velocity technique was used to characterize this mode. The velocity was measured up to a frequency of 160 kHz. Theoretical predictions of the velocities of these modes were also made and compared with experimental observations. Classical plate theory yields good agreement with the measured extensional velocities. For predictions of the dispersion of the flexural mode, Mindlin plates theory, which includes the effects of shear deformation and rotatory inertia was shown to give better agreement with the experimental measurements.

  12. Wide-Field Plate Database: Included Ukrainian Plate Catalogues

    NASA Astrophysics Data System (ADS)

    Tsvetkova, Katya; Sergeeva, Tetyana

    2007-08-01

    We present the basic information for the archives of the Main Astronomical Observatory of the National Academy of Sciences of Ukraine, included into the Wide-Field Plate Database last two years with total number of plates - 11260. The plates were obtained with the 0.40m Double Wide-angle Astrograph (DWA); 10cm, 11cm and 15cm Three Cameras Astrograph (TCA) and 12 cm Double Short focus Astrograph (DSA) in the period 1949-1998 in the frames of the following observing programmes: Photographic Survey of the Northern Sky; Investigation of the kinematics and the structure in the main meridian section of the Galaxy; selection of reference stars, minor planets observations, comet investigations.

  13. 30 CFR 20.13 - Approval plate.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... plate shall be satisfactory to MSHA. (a) Purpose of approval plate. The approval plate is a label which.... By it the manufacturer can point out that his lamp complies with specifications of MSHA and that it... place MSHA's approval plate on his lamp obligates the manufacturer to maintain the quality of...

  14. 49 CFR 451.23 - Plate specifications.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 6 2013-10-01 2013-10-01 false Plate specifications. 451.23 Section 451.23... SECURITY SAFETY APPROVAL OF CARGO CONTAINERS TESTING AND APPROVAL OF CONTAINERS Safety Approval Plate § 451.23 Plate specifications. (a) The safety approval plate must be of the size and in the...

  15. 49 CFR 451.23 - Plate specifications.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 6 2010-10-01 2010-10-01 false Plate specifications. 451.23 Section 451.23... SECURITY SAFETY APPROVAL OF CARGO CONTAINERS TESTING AND APPROVAL OF CONTAINERS Safety Approval Plate § 451.23 Plate specifications. (a) The safety approval plate must be of the size and in the...

  16. 49 CFR 451.23 - Plate specifications.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 6 2014-10-01 2014-10-01 false Plate specifications. 451.23 Section 451.23... SECURITY SAFETY APPROVAL OF CARGO CONTAINERS TESTING AND APPROVAL OF CONTAINERS Safety Approval Plate § 451.23 Plate specifications. (a) The safety approval plate must be of the size and in the...

  17. 49 CFR 451.23 - Plate specifications.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 6 2012-10-01 2012-10-01 false Plate specifications. 451.23 Section 451.23... SECURITY SAFETY APPROVAL OF CARGO CONTAINERS TESTING AND APPROVAL OF CONTAINERS Safety Approval Plate § 451.23 Plate specifications. (a) The safety approval plate must be of the size and in the...

  18. Beyond plate tectonics - Looking at plate deformation with space geodesy

    NASA Technical Reports Server (NTRS)

    Jordan, Thomas H.; Minster, J. Bernard

    1988-01-01

    The requirements that must be met by space-geodetic systems in order to constrain the horizontal secular motions associated with the geological deformation of the earth's surface are explored. It is suggested that in order to improve existing plate-motion models, the tangential components of relative velocities on interplate baselines must be resolved to an accuracy of less than 3 mm/yr. Results indicate that measuring the velocities between crustal blocks to + or - 5 mm/yr on 100-km to 1000-km scales can produce geologically significant constraints on the integrated deformation rates across continental plate-boundary zones such as the western United States.

  19. Plating on some difficult-to-plate metals and alloys

    SciTech Connect

    Dini, J.W.; Johnson, H.R.

    1980-02-01

    Electrodeposition of coatings on metals such as beryllium, beryllium-copper, Kovar, lead, magnesium, thorium, titanium, tungsten, uranium, zirconium, and their alloys can be problematic. This is due in most cases to a natural oxide surface film that readily reforms after being removed. The procedures we recommend for plating on these metals rely on replacing the oxide film with a displacement coating, or etching to allow mechanical keying between the substrate and plated deposit. The effectiveness of the procedures is demonstrated by interface bond strengths found in ring-shear and conical-head tensile tests.

  20. Plates for vacuum thermal fusion

    DOEpatents

    Davidson, James C.; Balch, Joseph W.

    2002-01-01

    A process for effectively bonding arbitrary size or shape substrates. The process incorporates vacuum pull down techniques to ensure uniform surface contact during the bonding process. The essence of the process for bonding substrates, such as glass, plastic, or alloys, etc., which have a moderate melting point with a gradual softening point curve, involves the application of an active vacuum source to evacuate interstices between the substrates while at the same time providing a positive force to hold the parts to be bonded in contact. This enables increasing the temperature of the bonding process to ensure that the softening point has been reached and small void areas are filled and come in contact with the opposing substrate. The process is most effective where at least one of the two plates or substrates contain channels or grooves that can be used to apply vacuum between the plates or substrates during the thermal bonding cycle. Also, it is beneficial to provide a vacuum groove or channel near the perimeter of the plates or substrates to ensure bonding of the perimeter of the plates or substrates and reduce the unbonded regions inside the interior region of the plates or substrates.

  1. Insert metering plates for gas turbine nozzles

    DOEpatents

    Burdgick, Steven S.; Itzel, Gary; Chopra, Sanjay; Abuaf, Nesim; Correia, Victor H.

    2004-05-11

    The invention comprises a metering plate which is assembled to an impingement insert for use in the nozzle of a gas turbine. The metering plate can have one or more metering holes and is used to balance the cooling flow within the nozzle. A metering plate with multiple holes reduces static pressure variations which result from the cooling airflow through the metering plate. The metering plate can be assembled to the insert before or after the insert is inserted into the nozzle.

  2. Surface crack problems in plates

    NASA Technical Reports Server (NTRS)

    Joseph, P. F.; Erdogan, F.

    1989-01-01

    The mode I crack problem in plates under membrane loading and bending is reconsidered. The purpose is to examine certain analytical features of the problem further and to provide some new results. The formulation and the results given by the classical and the Reissner plate theories for through and part-through cracks are compared. For surface cracks the three-dimensional finite element solution is used as the basis of comparison. The solution is obtained and results are given for the crack/contact problem in a plate with a through crack under pure bending and for the crack interaction problem. Also, a procedure is developed to treat the problem of subcritical crack growth and to trace the evolution of the propagating crack.

  3. Dual polarization flat plate antenna

    NASA Astrophysics Data System (ADS)

    Kelly, Kenneth C.

    Rectangular waveguides with radiating slots are used in groups to form planar array microwave antennas with large apertures and small depth. Such flat plate antennas are widely used on spacecraft and aircraft. Typically, flat plate antennas provide fixed linear polarization. The present paper describes a new flat plate antenna which produces two coincident beams that are distinguished by their orthogonal linear polarizations. The antenna has two ports, one for each of the coicident beams. Completely external to the antenna, connecting a simple network to those terminal ports enables the antenna to provide right circular polarization from one port and left from the other. A different external network enables the antenna to have arbitrarily adjustable polarizations.

  4. Achromatic axially symmetric wave plate.

    PubMed

    Wakayama, Toshitaka; Komaki, Kazuki; Otani, Yukitoshi; Yoshizawa, Toru

    2012-12-31

    An achromatic axially symmetric wave plate (AAS-WP) is proposed that is based on Fresnel reflections. The wave plate does not introduce spatial dispersion. It provides retardation in the wavelength domain with an axially symmetric azimuthal angle. The optical configuration, a numerical simulation, and the optical properties of the AAS-WP are described. It is composed of PMMA. A pair of them is manufactured on a lathe. In the numerical simulation, the achromatic angle is estimated and is used to design the devices. They generate an axially symmetric polarized beam. The birefringence distribution is measured in order to evaluate the AAS-WPs. PMID:23388751

  5. Overriding Plate Controls on Subduction Zone Evolution

    NASA Astrophysics Data System (ADS)

    Sharples, W. K.; Jadamec, M. A.; Moresi, L. N.; Capitanio, F. A.

    2014-12-01

    Seismic data, rock deformation experiments, and geochemical studies indicate variability in the thickness, buoyancy, and strength of the lithosphere at plate boundaries. However, geodynamic models of subduction commonly either omit an overriding plate or do not investigate role of the variation in overriding plate properties on the subduction evolution. We present time-dependent numerical models of subduction that vary the overriding plate thickness, strength, and density and allow for a plate interface that evolves with time via an anisotropic brittle failure rheology. We examine the emergence of (a) asymmetric versus symmetric subduction, (b) trench retreat versus advance, (c) subduction zone geometry, (d) slab stagnation versus penetration into the lower mantle, and (e) flat slab subduction. The majority of the models result in sustained asymmetric subduction. The models demonstrate that trench retreat is correlated with a thin overriding plate, whereas, trench advance is correlated with a thick and/or strong overriding plate. Slab dip, measured at a depth below the plate boundary interface, has a negative correlation with an increase in overriding plate thickness. Overriding plate thickness exerts a first order control over slab penetration into the lower mantle, with penetration most commonly occurring in models with a thick overriding plate. Periods of flat slab subduction occur with thick, strong overriding plates producing strong plate boundary interface coupling. The results provide insight into how the overriding plate plays a role in establishing advancing and retreating subduction, as well as providing an explanation for the variation of slab geometry observed in subduction zones on Earth.

  6. Elastic stability of thick auxetic plates

    NASA Astrophysics Data System (ADS)

    Lim, Teik-Cheng

    2014-04-01

    Auxetic materials and structures exhibit a negative Poisson’s ratio while thick plates encounter shear deformation, which is not accounted for in classical plate theory. This paper investigates the effect of a negative Poisson’s ratio on thick plates that are subjected to buckling loads, taking into consideration the shear deformation using Mindlin plate theory. Using a highly accurate shear correction factor that allows for the effect of Poisson’s ratio, the elastic stability of circular and square plates are evaluated in terms of dimensionless parameters, namely the Mindlin-to-Kirchhoff critical buckling load ratio and Mindlin critical buckling load factors. Results for thick square plates reveal that both parameters increase as the Poisson’s ratio becomes more negative. In the case of thick circular plates, the Mindlin-to-Kirchhoff critical buckling load ratios and the Mindlin critical buckling load factors increase and decrease, respectively, as the Poisson’s ratio becomes more negative. The results obtained herein show that thick auxetic plates behave as thin conventional plates, and therefore suggest that the classical plate theory can be used to evaluate the elastic stability of thick plates if the Poisson’s ratio of the plate material is sufficiently negative. The results also suggest that materials with highly negative Poisson’s ratios are recommended for square plates, but not circular plates, that are subjected to buckling loads.

  7. Petroleum occurrences and plate tectonics

    SciTech Connect

    Olenin, V.B.; Sokolov, B.A.

    1983-01-01

    This paper analyzes the mechanisms of petroleum formation and petroleum accumulation proposed in recent years by some Russian and foreign investigators from the viewpoint of the new global or plate tectonics. On the basis of discussion and the facts, the authors conclude that the mechanisms proposed are in contradiction to reality and their use in practical application is at least premature.

  8. Plated wire random access memories

    NASA Technical Reports Server (NTRS)

    Gouldin, L. D.

    1975-01-01

    A program was conducted to construct 4096-work by 18-bit random access, NDRO-plated wire memory units. The memory units were subjected to comprehensive functional and environmental tests at the end-item level to verify comformance with the specified requirements. A technical description of the unit is given, along with acceptance test data sheets.

  9. Corrosion resistant metallic bipolar plate

    DOEpatents

    Brady, Michael P.; Schneibel, Joachim H.; Pint, Bruce A.; Maziasz, Philip J.

    2007-05-01

    A corrosion resistant, electrically conductive component such as a bipolar plate for a PEM fuel cell includes 20 55% Cr, balance base metal such as Ni, Fe, or Co, the component having thereon a substantially external, continuous layer of chromium nitride.

  10. The seismotectonics of plate boundaries

    NASA Technical Reports Server (NTRS)

    Berger, J.; Brune, J. N.; Goodkind, J.; Wyatt, F.; Agnew, D. C.; Beaumont, C.

    1981-01-01

    Research on the seismotectonics of plate boundaries is summarized. Instrumental development and an observational program designed to study various aspects of the seismotectonics of southern California and the northern Gulf of California are described. A unique superconducting gravimeter was further developed and supported under this program for deployment and operation at several sites. Work on Earth tides is also discussed.

  11. Avionics Box Cold Plate Damage Prevention

    NASA Technical Reports Server (NTRS)

    Stambolian, Damon B.; Larchar, Steven W.; Henderson, Gena; Tran, Donald; Barth, Tim

    2012-01-01

    Problem Introduction: 1. Prevent Cold Plate Damage in Space Shuttle. 1a. The number of cold plate problems had increased from an average of 16.5 per/year between 1990 through 2000, to an average of 39.6 per year between 2001through 2005. 1b. Each complete set of 80 cold plates cost approximately $29 million, an average of $362,500 per cold plate. 1c It takes four months to produce a single cold plate. 2. Prevent Cold Plate Damage in Future Space Vehicles.

  12. Consecutive plate acoustic suppressor apparatus and methods

    NASA Technical Reports Server (NTRS)

    Doychak, Joseph (Inventor); Parrott, Tony (Inventor)

    1992-01-01

    An apparatus and method for suppressing acoustic noise utilizes consecutive plates, closely spaced to each other so as to exploit dissipation associated with sound propagation in narrow channels to optimize the acoustic resistance at a liner surface. The closely spaced plates can be utilized as high temperature structural materials for jet engines by constructing the plates from composite materials. Geometries of the plates, such as plate depth, shape, thickness, inter-plate spacing, arrangement, etc., can be selected to achieve bulk material-like behavior.

  13. Consecutive Plate Acoustic Suppressor Apparatus and Methods

    NASA Technical Reports Server (NTRS)

    Doychak, Joseph (Inventor); Parrott, Tony L. (Inventor)

    1993-01-01

    An apparatus and method for suppressing acoustic noise utilizes consecutive plates, closely spaced to each other so as to exploit dissipation associated with sound propagation in narrow channels to optimize the acoustic resistance at a liner surface. The closely spaced plates can be utilized as high temperature structural materials for jet engines by constructing the plates from composite materials. Geometries of the plates, such as plate depth, shape, thickness, inter-plate spacing, arrangement, etc., can be selected to achieve bulk material-like behavior.

  14. Maps, Plates, and Mount Saint Helens.

    ERIC Educational Resources Information Center

    Lary, Barbara E.; Krockover, Gerald H.

    1987-01-01

    Describes a laboratory activity on plate tectonics which focuses on the connection between plate tectonics and the different types of volcanoes. Provides questions for discussion and includes suggestions for extending the activity. (ML)

  15. Plating by glass-bead peening

    NASA Technical Reports Server (NTRS)

    Babecki, A. J.; Haehner, C. L.

    1971-01-01

    Technique permits plating of primarily metallic substrates with either metals or nonmetals at normal temperature. Peening uses compressed air to apply concurrent streams of small glass beads and powdered plating material to the substrate.

  16. 49 CFR 230.46 - Badge plates.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... TRANSPORTATION STEAM LOCOMOTIVE INSPECTION AND MAINTENANCE STANDARDS Boilers and Appurtenances Steam Gauges § 230.46 Badge plates. A metal badge plate showing the allowed steam pressure shall be attached to...

  17. 49 CFR 230.46 - Badge plates.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... TRANSPORTATION STEAM LOCOMOTIVE INSPECTION AND MAINTENANCE STANDARDS Boilers and Appurtenances Steam Gauges § 230.46 Badge plates. A metal badge plate showing the allowed steam pressure shall be attached to...

  18. 49 CFR 230.46 - Badge plates.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... TRANSPORTATION STEAM LOCOMOTIVE INSPECTION AND MAINTENANCE STANDARDS Boilers and Appurtenances Steam Gauges § 230.46 Badge plates. A metal badge plate showing the allowed steam pressure shall be attached to...

  19. 49 CFR 230.46 - Badge plates.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... TRANSPORTATION STEAM LOCOMOTIVE INSPECTION AND MAINTENANCE STANDARDS Boilers and Appurtenances Steam Gauges § 230.46 Badge plates. A metal badge plate showing the allowed steam pressure shall be attached to...

  20. 49 CFR 230.46 - Badge plates.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... TRANSPORTATION STEAM LOCOMOTIVE INSPECTION AND MAINTENANCE STANDARDS Boilers and Appurtenances Steam Gauges § 230.46 Badge plates. A metal badge plate showing the allowed steam pressure shall be attached to...

  1. Aluminum transfer method for plating plastics

    NASA Technical Reports Server (NTRS)

    Goodrich, W. D.; Stalmach, C. J., Jr.

    1977-01-01

    Electroless plating technique produces plate of uniform thickness. Hardness and abrasion resistance can be increased further by heat treatment. Method results in seamless coating over many materials, has low thermal conductivity, and is relatively inexpensive compared to conventional methods.

  2. Electrically induced mechanical precompression of ferroelectric plates

    DOEpatents

    Chen, P.J.

    1987-03-02

    A method of electrically inducing mechanical precompression of ferroelectric plate covered with electrodes utilizes the change in strains of the plate as functions of applied electric field. A first field polarizes and laterally shrinks the entire plate. An outer portion of the electrodes are removed, and an opposite field partially depolarizes and expands the central portion of the plate against the shrunk outer portion. 2 figs.

  3. Practical automatic Arabic license plate recognition system

    NASA Astrophysics Data System (ADS)

    Mohammad, Khader; Agaian, Sos; Saleh, Hani

    2011-02-01

    Since 1970's, the need of an automatic license plate recognition system, sometimes referred as Automatic License Plate Recognition system, has been increasing. A license plate recognition system is an automatic system that is able to recognize a license plate number, extracted from image sensors. In specific, Automatic License Plate Recognition systems are being used in conjunction with various transportation systems in application areas such as law enforcement (e.g. speed limit enforcement) and commercial usages such as parking enforcement and automatic toll payment private and public entrances, border control, theft and vandalism control. Vehicle license plate recognition has been intensively studied in many countries. Due to the different types of license plates being used, the requirement of an automatic license plate recognition system is different for each country. [License plate detection using cluster run length smoothing algorithm ].Generally, an automatic license plate localization and recognition system is made up of three modules; license plate localization, character segmentation and optical character recognition modules. This paper presents an Arabic license plate recognition system that is insensitive to character size, font, shape and orientation with extremely high accuracy rate. The proposed system is based on a combination of enhancement, license plate localization, morphological processing, and feature vector extraction using the Haar transform. The performance of the system is fast due to classification of alphabet and numerals based on the license plate organization. Experimental results for license plates of two different Arab countries show an average of 99 % successful license plate localization and recognition in a total of more than 20 different images captured from a complex outdoor environment. The results run times takes less time compared to conventional and many states of art methods.

  4. Electrically induced mechanical precompression of ferroelectric plates

    DOEpatents

    Chen, Peter J.

    1987-01-01

    A method of electrically inducing mechanical precompression of a ferroelectric plate covered with electrodes utilizes the change in strains of the plate as functions of applied electric field. A first field polarizes and laterally shrinks the entire plate. An outer portion of the electrodes are removed, and an opposite field partially depolarizes and expands the central portion of the plate against the shrunk outer portion.

  5. Electrochemical Assay of Gold-Plating Solutions

    NASA Technical Reports Server (NTRS)

    Chiodo, R.

    1982-01-01

    Gold content of plating solution is assayed by simple method that required only ordinary electrochemical laboratory equipment and materials. Technique involves electrodeposition of gold from solution onto electrode, the weight gain of which is measured. Suitable fast assay methods are economically and practically necessary in electronics and decorative-plating industries. If gold content in plating bath is too low, poor plating may result, with consequent economic loss to user.

  6. Ion plated electronic tube device

    DOEpatents

    Meek, T.T.

    1983-10-18

    An electronic tube and associated circuitry which is produced by ion plating techniques. The process is carried out in an automated process whereby both active and passive devices are produced at very low cost. The circuitry is extremely reliable and is capable of functioning in both high radiation and high temperature environments. The size of the electronic tubes produced are more than an order of magnitude smaller than conventional electronic tubes.

  7. Electroless metal plating of plastics

    DOEpatents

    Krause, L.J.

    1982-09-20

    Process for plating main group metals on aromatic polymers is carried out by the use of a nonaqueous solution of a salt of an alkali metal in a positive valence state and a main group metal in a negative valence state with contact between the solution and polymer providing a redox reaction causing the deposition of the main group metal and the reduction of the polymer. Products from the process exhibit useful decorative and electrical properties.

  8. Electroless metal plating of plastics

    DOEpatents

    Krause, Lawrence J.

    1986-01-01

    Process for plating main group metals on aromatic polymers is carried out by the use of a nonaqueous solution of a salt of an alkali metal in a positive valence state and a main group metal in a negative valence state with contact between the solution and polymer providing a redox reaction causing the deposition of the main group metal and the reduction of the polymer. Products from the process exhibit useful decorative and electrical properties.

  9. Electroless metal plating of plastics

    DOEpatents

    Krause, Lawrence J.

    1984-01-01

    Process for plating main group metals on aromatic polymers is carried out by the use of a nonaqueous solution of a salt of an alkali metal in a positive valence state and a main group metal in a negative valence state with contact between the solution and polymer providing a redox reaction causing the deposition of the main group metal and the reduction of the polymer. Products from the process exhibit useful decorative and electrical properties.

  10. PRETREATING URANIUM FOR METAL PLATING

    DOEpatents

    Wehrmann, R.F.

    1961-05-01

    A process is given for anodically treating the surface of uranium articles, prior to metal plating. The metal is electrolyzed in an aqueous solution of about 10% polycarboxylic acid, preferably oxalic acid, from 1 to 5% by weight of glycerine and from 1 to 5% by weight of hydrochloric acid at from 20 to 75 deg C for from 30 seconds to 15 minutes. A current density of from 60 to 100 amperes per square foot is used.

  11. Syncytial-Type Cell Plates

    PubMed Central

    Otegui, Marisa; Staehelin, L. Andrew

    2000-01-01

    Cell wall formation in the syncytial endosperm of Arabidopsis was studied by using high-pressure-frozen/freeze-substituted developing seeds and immunocytochemical techniques. The endosperm cellularization process begins at the late globular embryo stage with the synchronous organization of small clusters of oppositely oriented microtubules (∼10 microtubules in each set) into phragmoplast-like structures termed mini-phragmoplasts between both sister and nonsister nuclei. These mini-phragmoplasts produce a novel kind of cell plate, the syncytial-type cell plate, from Golgi-derived vesicles ∼63 nm in diameter, which fuse by way of hourglass-shaped intermediates into wide (∼45 nm in diameter) tubules. These wide tubules quickly become coated and surrounded by a ribosome-excluding matrix; as they grow, they branch and fuse with each other to form wide tubular networks. The mini-phragmoplasts formed between a given pair of nuclei produce aligned tubular networks that grow centrifugally until they merge into a coherent wide tubular network with the mini-phragmoplasts positioned along the network margins. The individual wide tubular networks expand laterally until they meet and eventually fuse with each other at the sites of the future cell corners. Transformation of the wide tubular networks into noncoated, thin (∼27 nm in diameter) tubular networks begins at multiple sites and coincides with the appearance of clathrin-coated budding structures. After fusion with the syncytial cell wall, the thin tubular networks are converted into fenestrated sheets and cell walls. Immunolabeling experiments show that the cell plates and cell walls of the endosperm differ from those of the embryo and maternal tissue in two features: their xyloglucans lack terminal fucose residues on the side chain, and callose persists in the cell walls after the cell plates fuse with the parental plasma membrane. The lack of terminal fucose residues on xyloglucans suggests that these cell wall

  12. Episodic plate tectonics on Venus

    NASA Technical Reports Server (NTRS)

    Turcotte, Donald

    1992-01-01

    Studies of impact craters on Venus from the Magellan images have placed important constraints on surface volcanism. Some 840 impact craters have been identified with diameters ranging from 2 to 280 km. Correlations of this impact flux with craters on the Moon, Earth, and Mars indicate a mean surface age of 0.5 +/- 0.3 Ga. Another important observation is that 52 percent of the craters are slightly fractured and only 4.5 percent are embayed by lava flows. These observations led researchers to hypothesize that a pervasive resurfacing event occurred about 500 m.y. ago and that relatively little surface volcanism has occurred since. Other researchers have pointed out that a global resurfacing event that ceased about 500 MYBP is consistent with the results given by a recent study. These authors carried out a series of numerical calculations of mantle convection in Venus yielding thermal evolution results. Their model considered crustal recycling and gave rapid planetary cooling. They, in fact, suggested that prior to 500 MYBP plate tectonics was active in Venus and since 500 MYBP the lithosphere has stabilized and only hot-spot volcanism has reached the surface. We propose an alternative hypothesis for the inferred cessation of surface volcanism on Venus. We hypothesize that plate tectonics on Venus is episodic. Periods of rapid plate tectonics result in high rates of subduction that cool the interior resulting in more sluggish mantle convection.

  13. Volcano spacing and plate rigidity

    SciTech Connect

    Brink, U. )

    1991-04-01

    In-plane stresses, which accompany the flexural deformation of the lithosphere under the load adjacent volcanoes, may govern the spacing of volcanoes in hotspot provinces. Specifically, compressive stresses in the vicinity of a volcano prevent new upwelling in this area, forcing a new volcano to develop at a minimum distance that is equal to the distance in which the radial stresses change from compressional to tensile (the inflection point). If a volcano is modeled as a point load on a thin elastic plate, then the distance to the inflection point is proportional to the thickness of the plate to the power of 3/4. Compilation of volcano spacing in seven volcanic groups in East Africa and seven volcanic groups of oceanic hotspots shows significant correlation with the elastic thickness of the plate and matches the calculated distance to the inflection point. In contrast, volcano spacing in island arcs and over subduction zones is fairly uniform and is much larger than predicted by the distance to the inflection point, reflecting differences in the geometry of the source and the upwelling areas.

  14. Plating of proximal humeral fractures.

    PubMed

    Martetschläger, Frank; Siebenlist, Sebastian; Weier, Michael; Sandmann, Gunther; Ahrens, Philipp; Braun, Karl; Elser, Florian; Stöckle, Ulrich; Freude, Thomas

    2012-11-01

    The optimal treatment for proximal humeral fractures is controversial. Few data exist concerning the influence of the surgical approach on the outcome. The purpose of this study was to evaluate the clinical and radiological outcomes of proximal humeral fractures treated with locking plate fixation through a deltopectoral vs an anterolateral deltoid-splitting approach. Of 86 patients who met the inclusion criteria, 70 were available for follow-up examination. Thirty-three patients were treated through a deltopectoral approach and 37 through an anterolateral deltoid-splitting approach. In all cases, open reduction and internal fixation with a PHILOS locking plate (Synthes, Umkirch, Germany) was performed. Clinical follow-up included evaluation of pain, shoulder mobility, and strength. Constant score and Disabilities of the Arm, Shoulder and Hand (DASH) score were assessed. A clinical neurological examination of the axillary nerve was also performed. Consolidation, reduction, and appearance of head necrosis were evaluated radiographically. After a mean follow-up of 33 months, Constant scores, DASH scores, and American Shoulder and Elbow Surgeons scores showed no significant differences between the groups. Clinical neurologic examination of the axillary nerve revealed no obvious damage to the nerve in either group. Deltopectoral and anterolateral detoid-splitting approaches for plate fixation of proximal humeral fractures are safe and provide similar clinical outcomes. The results of this study suggest that the approach can be chosen according to surgeon preference. PMID:23127451

  15. MTR plates modeling with MAIA

    SciTech Connect

    Marelle, V.; Dubois, S.; Ripert, M.; Noirot, J.

    2008-07-15

    MAIA is a thermo-mechanical code dedicated to the modeling of MTR fuel plates. The main physical phenomena modeled in the code are the cladding oxidation, the interaction between fuel and Al-matrix, the swelling due to fission products and the Al/fuel particles interaction. The creeping of the plate can be modeled in the mechanical calculation. MAIA has been validated on U-Mo dispersion fuel experiments such as IRIS 1 and 2 and FUTURE. The results are in rather good agreement with post-irradiation examinations. MAIA can also be used to calculate in-pile behavior of U{sub 3}Si{sub 2} plates as in the SHARE experiment irradiated in the SCK/Mol BR2 reactor. The main outputs given by MAIA throughout the irradiation are temperatures, cladding oxidation thickness, interaction thickness, volume fraction of meat constituents, swelling, displacements, strains and stresses. MAIA is originally a two-dimensional code but a three-dimensional version is currently under development. (author)

  16. 24 CFR 3280.5 - Data plate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 24 Housing and Urban Development 5 2014-04-01 2014-04-01 false Data plate. 3280.5 Section 3280.5... MANUFACTURED HOME CONSTRUCTION AND SAFETY STANDARDS General § 3280.5 Data plate. Each manufactured home shall bear a data plate affixed in a permanent manner near the main electrical panel or other...

  17. 24 CFR 3280.5 - Data plate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 24 Housing and Urban Development 5 2012-04-01 2012-04-01 false Data plate. 3280.5 Section 3280.5... MANUFACTURED HOME CONSTRUCTION AND SAFETY STANDARDS General § 3280.5 Data plate. Each manufactured home shall bear a data plate affixed in a permanent manner near the main electrical panel or other...

  18. 24 CFR 3280.5 - Data plate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 24 Housing and Urban Development 5 2011-04-01 2011-04-01 false Data plate. 3280.5 Section 3280.5... MANUFACTURED HOME CONSTRUCTION AND SAFETY STANDARDS General § 3280.5 Data plate. Each manufactured home shall bear a data plate affixed in a permanent manner near the main electrical panel or other...

  19. 24 CFR 3280.5 - Data plate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 24 Housing and Urban Development 5 2013-04-01 2013-04-01 false Data plate. 3280.5 Section 3280.5... MANUFACTURED HOME CONSTRUCTION AND SAFETY STANDARDS General § 3280.5 Data plate. Each manufactured home shall bear a data plate affixed in a permanent manner near the main electrical panel or other...

  20. 24 CFR 3280.5 - Data plate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 24 Housing and Urban Development 5 2010-04-01 2010-04-01 false Data plate. 3280.5 Section 3280.5... MANUFACTURED HOME CONSTRUCTION AND SAFETY STANDARDS General § 3280.5 Data plate. Each manufactured home shall bear a data plate affixed in a permanent manner near the main electrical panel or other...

  1. Moving Divertor Plates in a Tokamak

    SciTech Connect

    S.J. Zweben, H. Zhang

    2009-02-12

    Moving divertor plates could help solve some of the problems of the tokamak divertor through mechanical ingenuity rather than plasma physics. These plates would be passively heated on each pass through the tokamak and cooled and reprocessed outside the tokamak. There are many design options using varying plate shapes, orientations, motions, coatings, and compositions.

  2. Recent plate motions and crustal deformation

    SciTech Connect

    Lisowski, M. )

    1991-01-01

    Reports by U.S. workers on geodetic measurements of recent plate motions or crustal deformation published in 1987-1990 are reviewed. The review begins with global plate motions, proceeds through plate boundaries in California, Alaska, and the Pacific Northwest, and finishes with volcanic phenomena, monument stability and longevity, and GPS relative position measurements. 184 refs.

  3. 49 CFR 213.123 - Tie plates.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Tie plates. 213.123 Section 213.123 Transportation... TRANSPORTATION TRACK SAFETY STANDARDS Track Structure § 213.123 Tie plates. (a) In Classes 3 through 5 track where timber crossties are in use there shall be tie plates under the running rails on at least eight...

  4. 46 CFR 169.665 - Name plates.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 false Name plates. 169.665 Section 169.665 Shipping COAST... Gross Tons § 169.665 Name plates. Each generator, motor and other major item f power equipment must be provided with a name plate indicating the manufacturer's name, its rating in volts and amperes or in...

  5. 46 CFR 169.665 - Name plates.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 false Name plates. 169.665 Section 169.665 Shipping COAST... Gross Tons § 169.665 Name plates. Each generator, motor and other major item f power equipment must be provided with a name plate indicating the manufacturer's name, its rating in volts and amperes or in...

  6. 46 CFR 169.665 - Name plates.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Name plates. 169.665 Section 169.665 Shipping COAST... Gross Tons § 169.665 Name plates. Each generator, motor and other major item f power equipment must be provided with a name plate indicating the manufacturer's name, its rating in volts and amperes or in...

  7. 46 CFR 169.665 - Name plates.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Name plates. 169.665 Section 169.665 Shipping COAST... Gross Tons § 169.665 Name plates. Each generator, motor and other major item f power equipment must be provided with a name plate indicating the manufacturer's name, its rating in volts and amperes or in...

  8. 46 CFR 169.665 - Name plates.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false Name plates. 169.665 Section 169.665 Shipping COAST... Gross Tons § 169.665 Name plates. Each generator, motor and other major item f power equipment must be provided with a name plate indicating the manufacturer's name, its rating in volts and amperes or in...

  9. Forming Weld Lands On Metal Plates

    NASA Technical Reports Server (NTRS)

    Weddendorf, Bruce

    1994-01-01

    Forming shoe pounds edge of newly inserted plate workpiece. After many passes of shoe and advances of plate, thick land builds up at edge. Workpiece heated to enable metal to flow without strain hardening. Proposed upset-forming process replaces relatively expensive, time-consuming, and wasteful process in which integral weld lands created by machining metal away from plates everywhere except at lands.

  10. 21 CFR 872.4760 - Bone plate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Bone plate. 872.4760 Section 872.4760 Food and... DENTAL DEVICES Surgical Devices § 872.4760 Bone plate. (a) Identification. A bone plate is a metal device intended to stabilize fractured bone structures in the oral cavity. The bone segments are attached to...

  11. FASTENER FOR AN ASSEMBLY OF PLATES

    DOEpatents

    Groh, E.F.

    1963-08-20

    A fastener is provided for a spaced-apart parallel plate fuel assembly. The fastener, attached by screws to a key that passes through the edges of the assembled plate, serves as a retainer for the outermost plate as well as a bidirectional spacer for separating the fuel assembly from two neighboring fuel assemblies. (AEC)

  12. Normal-Pressure Tests of Rectangular Plates

    NASA Technical Reports Server (NTRS)

    Ramberg, Walter; Mcpherson, Albert E; Levy, Samuel

    1942-01-01

    Report presents the results of normal-pressure tests made of 56 rectangular plates with clamped edges and of 5 plates with freely supported edges. Pressure was applied and the center deflection and the permanent set at the center were measured. For some of the plates, in addition, strains and contours were measured.

  13. 21 CFR 872.4760 - Bone plate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Bone plate. 872.4760 Section 872.4760 Food and... DENTAL DEVICES Surgical Devices § 872.4760 Bone plate. (a) Identification. A bone plate is a metal device intended to stabilize fractured bone structures in the oral cavity. The bone segments are attached to...

  14. The critical shear load of rectangular plates

    NASA Technical Reports Server (NTRS)

    Seydel, Edgar

    1933-01-01

    This report gives formulas for analyzing the critical shear load of a simply supported square, isotropic (simple flat plate), or orthogonal anisotropic plate (a plate in which the rigidity in two directions perpendicular to each other is different, i.e. plywood or corrugated sheet), these formulas, although arrived at by approximation method, seem to agree fairly well with experimental results.

  15. Apparatus and method for controlling plating uniformity

    DOEpatents

    Hachman Jr., John T.; Kelly, James J.; West, Alan C.

    2004-10-12

    The use of an insulating shield for improving the current distribution in an electrochemical plating bath is disclosed. Numerical analysis is used to evaluate the influence of shield shape and position on plating uniformity. Simulation results are compared to experimental data for nickel deposition from a nickel--sulfamate bath. The shield is shown to improve the average current density at a plating surface.

  16. 49 CFR 451.23 - Plate specifications.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 6 2011-10-01 2011-10-01 false Plate specifications. 451.23 Section 451.23 Transportation Other Regulations Relating to Transportation (Continued) COAST GUARD, DEPARTMENT OF HOMELAND SECURITY SAFETY APPROVAL OF CARGO CONTAINERS TESTING AND APPROVAL OF CONTAINERS Safety Approval Plate § 451.23 Plate specifications. (a) The...

  17. Plate tectonics, habitability and life

    NASA Astrophysics Data System (ADS)

    Spohn, Tilman; Breuer, Doris

    2016-04-01

    The role of plate tectonics in defining habitability of terrestrial planets is being increasingly discussed (e.g., Elkins-Tanton, 2015). Plate tectonics is a significantly evolved concept with a large variety of aspects. In the present context, cycling of material between near surface and mantle reservoirs is most important. But increased heat transport through mixing of cold lithosphere with the deep interior and formation of continental crust may also matter. An alternative mechanism of material cycling between these reservoirs is hot-spot volcanism combined with crust delamination. Hot-spot volcanism will transport volatiles to the atmosphere while delamination will mix crust, possibly altered by sedimentation and chemical reactions, with the mantle. The mechanism works as long as the stagnant lithosphere plate has not grown thicker than the crust and as long as volcanic material is added onto the crust. Thermal evolution studies suggest that the mechanism could work for the first 1-2 Ga of planetary evolution. The efficiency of the mechanism is limited by the ratio of extrusive to intrusive volcanism, which is thought to be less than 0.25. Plate tectonics would certainly have an advantage by working even for more evolved planets. A simple, most-used concept of habitability requires the thermodynamic stability of liquid water on the surface of a planet. Cycling of CO2between the atmosphere, oceans and interior through subduction and surface volcanism is an important element of the carbonate-silicate cycle, a thermostat feedback cycle that will keep the atmosphere from entering into a runaway greenhouse. Calculations for a model Earth lacking plate tectonics but degassing CO2, N, and H2O to form a surface ocean and a secondary atmosphere (Tosi et al, 2016) suggest that liquid water can be maintained on the surface for 4.5Ga. The model planet would then qualify as habitable. It is conceivable that the CO2 buffering capability of its ocean together with silicate

  18. Peridinialean dinoflagellate plate patterns, labels and homologies

    USGS Publications Warehouse

    Edwards, L.E.

    1990-01-01

    Tabulation patterns for peridinialean dinoflagellate thecae and cysts have been traditionally expressed using a plate labelling system described by C.A. Kofoid in the early 1900's. This system can obscure dinoflagellate plate homologies and has not always been strictly applied. The plate-labelling system presented here introduces new series labels but incorporates key features and ideas from the more recently proposed systems of G.L. Eaton and F.J.R. Taylor, as modified by W.R. Evitt. Plate-series recognition begins with the cingulum (C-series) and proceeds from the cingulum toward the apex for the three series of the epitheca/epicyst and proceeds from the cingulum toward the antapex for the two series of the hypotheca/hypocyst. The epithecal/epicystal model consists of eight plates that touch the anterior margin of the cingulum (E-series: plates E1-E7, ES), seven plates toward the apex that touch the E-series plates (M-series: R, M1-M6), and up to seven plates near the apex that do not touch E-series plates (D-series: Dp-Dv). The hypothecal/hypocystal model consists of eight plates that touch the posterior margin of the cingulum (H-series: H1-H6,HR,HS) and three plates toward the antapex (T1-T3). Epithecal/epicystal tabulation patterns come in both 8- and 7- models, corresponding to eight and seven plates, respectively, in the E-series. Hypothecal/hypocystal tabulation patterns also come in both 8- and 7-models, corresponding to eight and seven plates, respectively, in the H-series. By convention, the 7-model epitheca/epicyst has no plates E1 and M1; the 7-model hypotheca/hypocyst has no plate H6. Within an 8-model or 7-model, the system emphasizes plates that are presumed to be homologous by giving them identical labels. I introduce the adjectives "monothigmate", "dithigmate," and "trithigmate" to designate plates touching one, two, and three plates, respectively, of the adjacent series. The term "thigmation" applies to the analysis of plate contacts between

  19. Development of flat-plate solar plate collector: Evaporator

    NASA Astrophysics Data System (ADS)

    Abramzon, B.; Yaron, I.

    1981-11-01

    In the present study the thermal performance of a flat plate solar collector is analyzed theoretically for the case in which the working fluid may undergo a phase change within the tubes of the collector. In addition to the common domestic applications, such a collector - evaporator may be used as a generator of vapors for the production of mechanical or electrical energy, e.g., solar water pumps, solar power stations, etc., as well as for solar - powered absorption refrigeration machines, distillation installations, etc.

  20. Separator plate for a fuel cell

    DOEpatents

    Petri, R.J.; Meek, J.; Bachta, R.P.; Marianowski, L.G.

    1996-04-02

    A separator plate is described for a fuel cell comprising an anode current collector, a cathode current collector and a main plate, the main plate disposed between the anode current collector and the cathode current collector. The anode current collector forms a flattened peripheral wet seal structure and manifold wet seal structure on the anode side of the separator plate and the cathode current collector forms a flattened peripheral wet seal structure and manifold wet seal structure on the cathode side of the separator plate. In this manner, the number of components required to manufacture and assemble a fuel cell stack is reduced. 9 figs.

  1. Separator plate for a fuel cell

    DOEpatents

    Petri, Randy J.; Meek, John; Bachta, Robert P.; Marianowski, Leonard G.

    1996-01-01

    A separator plate for a fuel cell comprising an anode current collector, a cathode current collector and a main plate, the main plate disposed between the anode current collector and the cathode current collector. The anode current collector forms a flattened peripheral wet seal structure and manifold wet seal structure on the anode side of the separator plate and the cathode current collector forms a flattened peripheral wet seal structure and manifold wet seal structure on the cathode side of the separator plate. In this manner, the number of components required to manufacture and assemble a fuel cell stack is reduced.

  2. Steady state response of unsymmetrically laminated plates

    SciTech Connect

    Hosokawa, Kenji; Kawashima, Katsuya; Sakata, Toshiyuki

    1995-11-01

    A numerical approach for analyzing the forced vibration problem of a symmetrically laminated FRP (fiber reinforced plastic) composite plate was proposed by the authors. In the present paper, this approach is modified for application to an unsymmetrically laminated FRP composite plate. Numerical calculations are carried out for the clamped antisymmetrically laminated rectangular and elliptical plates which are a kind of unsymmetrically laminated plate. Then,, the effects of the lamina material and the fiber orientation angle on the steady state response are discussed. Furthermore, it is investigated that what structural damping factor is most influenced on the steady state response of an antisymmetrically laminated plate.

  3. Shear deformation in thick auxetic plates

    NASA Astrophysics Data System (ADS)

    Lim, Teik-Cheng

    2013-08-01

    This paper aims to understand the effect of auxeticity on shear deformation in thick plates. Three models for the shear correction factor of plates as a function of Poisson’s ratio were proposed: an analytical model, a cubic fit model and a modified model. Of these three, the cubic fit model exhibits the best accuracy over the entire range of Poisson’s ratio from -1 to 0.5. The extent of shear deformation is herein investigated using the example of uniformly loaded circular plates. It was found that the maximum deformation of such plates based on Mindlin theory approximates to those according to Kirchhoff theory when the Poisson’s ratio of the plate material is highly negative. When the Poisson’s ratio of the plate material is -1 and the edge of the plate is simply supported, the calculation of the maximum deflection by Mindlin theory simplifies into that by Kirchhoff theory. These results suggest that auxeticity reduces shear deformation in thick plates, permitting the use of classical plate theory for thick plates only if the plate material is highly auxetic.

  4. An understanding of HSLA-65 plate steels

    NASA Astrophysics Data System (ADS)

    Sampath, K.

    2006-02-01

    HSLA-65 plate steels can be produced using one of five plate manufacturing techniques: normalizing, controlled rolling (CR), controlled rolling followed by accelerated cooling (CR-AC), direct quenching and tempering (DQT), or conventional quenching and tempering (Q&T). The HSLA-65 steels are characterized by low carbon content and low alloy content, and they exhibit a low carbon equivalent that allows improved plate weldability. These characteristics in turn (a) provide the steel plate with a refined microstructure that ensures high strength and toughness; (b) eliminate or substantially reduce the need for preheating during welding; (c) resist susceptibility to hydrogen-assisted cracking (HAC) in the weld heat affected zone (HAZ) when fusion (arc) welded using low heat-input conditions; and (d) depending on section thickness, facilitate high heat-input welding (about 2 kJ/mm) without significant loss of strength or toughness in the HAZ. However, application of this plate manufacturing process and of these controls produces significant differences in the metallurgical structure and range of mechanical properties of the HSLA-65 plate steels both among themselves and versus conventional higher strength steel (HSS) plates. For example, among the HSLA-65 plate steels, those produced by Q&T exhibit minimal variability in mechanical properties, especially in thicker plates. Besides variability in mechanical properties depending on plate thickness, the CR and CR-AC plate steels exhibit a relatively higher yield strength to ultimate tensile strength (YS/UTS) ratio than do DQT and Q&T steels. Such differences in processing and properties of HSLA-65 plate steels could potentially affect the selection and control of various secondary fabrication practices, including arc welding. Consequently, fabricators must exercise extreme caution when transferring allowable limits of certified secondary fabrication practices from one type of HSLA-65 plate steel to another, even for the

  5. When Did Plate Tectonics Begin

    NASA Astrophysics Data System (ADS)

    Brown, M.

    2015-12-01

    Present-day plate tectonics on Earth is characterized by asymmetric (one-sided) subduction, but how do we recognize the imprint of subduction in the geologic record? How do we weigh global (commonly younger) vs local (commonly older) datasets or distinguish initiation from episodic from continuous subduction? How reliable are data gaps? Characteristics of the Paleozoic record of subduction include calc-alkaline magmatism, blueschist/UHP metamorphism and collisional orogenesis, and ophiolites as representatives of former ocean lithosphere. Are these characteristic rocks preserved in Proterozoic, Archean and Hadean crust? Does a hotter mantle, higher heat production and weaker lithosphere modify or eliminate these features? What preceded subduction and how do we recognize that regime? Are rock associations or geochemical fingerprints reliable? Does reworking and overprinting modify geochemical fingerprints? Proposals for the start of plate tectonics have been based on: persistence of isotope anomalies/fractionated chemical domains in the mantle; changes in chemistry of magmatic rocks, rates of crustal growth vs reworking, and sites of growth; the metamorphic record, particularly the first appearance of contrasting thermal gradients or eclogite (including evidence from mineral inclusions in diamonds) or UHP metamorphic rocks; stabilization of cratonic lithosphere and formation of supercratons, and the beginning of the Proterozoic supercontinent cycle; the end of the flat Earth, emergence of continents, development of significant topography, changes in the style of orogeny and the rise in atmospheric oxygen; and, the appearance of passive margins and changes in the style of sedimentation. Estimates of the timing have varied from the Hadean to Neoproterozoic. I will summarize evidence for a growing consensus that the late Mesoarchean to early Paleoproterozoic was a 700 Myr long period of transition to continuous (?) subduction and global (?) mobile-lid plate tectonics.

  6. Tectonic speed limits from plate kinematic reconstructions

    NASA Astrophysics Data System (ADS)

    Zahirovic, Sabin; Müller, R. Dietmar; Seton, Maria; Flament, Nicolas

    2015-05-01

    The motion of plates and continents on the planet's surface are a manifestation of long-term mantle convection and plate tectonics. Present-day plate velocities provide a snapshot of this ongoing process, and have been used to infer controlling factors on the speeds of plates and continents. However, present-day velocities do not capture plate behaviour over geologically representative periods of time. To address this shortcoming, we use a plate tectonic reconstruction approach to extract time-dependent plate velocities and geometries from which root mean square (RMS) velocities are computed, resulting in a median RMS plate speed of ∼ 4 cm /yr over 200 Myr. Linking tectonothermal ages of continental lithosphere to the RMS plate velocity analysis, we find that the increasing portions of plate area composed of continental and/or cratonic lithosphere significantly reduces plate speeds. Plates with any cratonic portion have a median RMS velocity of ∼ 5.8 cm /yr, while plates with more than 25% of cratonic area have a median RMS speed of ∼ 2.8 cm /yr. The fastest plates (∼ 8.5 cm /yr RMS speed) have little continental fraction and tend to be bounded by subduction zones, while the slowest plates (∼ 2.6- 2.8 cm /yr RMS speed) have large continental fractions and usually have little to no subducting part of plate perimeter. More generally, oceanic plates tend to move 2-3 times faster than continental plates, consistent with predictions of numerical models of mantle convection. The slower motion of continental plates is compatible with deep keels impinging on asthenospheric flow and increasing shear traction, thus anchoring the plate in the more viscous mantle transition zone. We also find that short-lived (up to ∼ 10 Myr) rapid accelerations of Africa (∼100 and 65 Ma), North America (∼100 and 55 Ma) and India (∼ 130 , 80 and 65 Ma) appear to be correlated with plume head arrivals as recorded by large igneous province (LIPs) emplacement. By evaluating

  7. Turbulent flows near flat plates

    NASA Astrophysics Data System (ADS)

    Kambe, R.; Imamura, T.; Doi, M.

    1980-08-01

    The method to study the effect of the plate moving in the homogeneous or isotropic turbulence is presented. The crucial point of this method is to solve the Orr-Sommerfeld like equation, which is satisfied by the kernel of the Wiener-Hermite expansion of the velocity field, under the inhomogeneous boundary condition. In the special case of constant mean flow, our method gives the same result as that of Hunt and Graham and succeeds in explaining the experimental results of Thomas and Hancock. The method is also applied to the case of nonuniform mean flow, where the shear effect comes up.

  8. Non-cyanide silver plating

    SciTech Connect

    Dini, J.W.

    1995-11-07

    Lawrence Livermore National Laboratory (LLNL) and Technic, Inc. have entered into a CRADA (Cooperative Research and Development Agreement) with the goal of providing industry with an environmentally benign alternative to the presently used silver cyanide plating process. This project has been in place for about six months and results are quite promising. The main objective, that of deposition of deposits as thick as 125 um (5 mils), has been met. Property data such as stress and hardness have been obtained and the structure of the deposit has been analyzed via metallography and x-ray diffraction. These results will be presented in this paper, along with plans for future work.

  9. Coarse Layering at 'Home Plate'

    NASA Technical Reports Server (NTRS)

    2006-01-01

    This image shows coarse-grained layers from around the edge of a low plateau called 'Home Plate' inside Mars' Gusev Crater. One possible origin is material falling to the ground after being thrown aloft by an explosion such as a volcanic eruption or meteorite impact.

    The panoramic camera (Pancam) on NASA's Mars Exploration Rover Spirit acquired the exposures for this image on Spirit's 749th Martian day (Feb. 10, 2006). This view is an approximately true-color rendering mathematically generated from separate images taken through all of the left Pancam's 432-nanometer to 753-nanometer filters.

  10. Adherent protective coatings plated on magnesium-lithium alloy

    NASA Technical Reports Server (NTRS)

    1965-01-01

    Zinc is plated on a magnesium-lithium alloy by using a modification of the standard zinc-plate immersion bath. Further protection is given the alloy by applying a light plating of copper on the zinc plating. Other metals are plated on the copper by using conventional plating baths.

  11. A Refined Shear Deformation Plate Theory

    NASA Astrophysics Data System (ADS)

    Liu, Yucheng

    2011-04-01

    An improved higher-order shear deformation theory of plates is presented in this paper. The theory is developed from the transverse shear deformation theory presented by Ambartsumian [11]. The present plate theory contains kinematics of higher-order displacement field of plates, a system of higher-order differential equilibrium equations in terms of the three generalized displacements of bending plates, and a system of boundary conditions at each edge of plate boundaries. The present shear deformation theory of plates is validated by applying it to solve torsional plates and simply supported plates. The obtained solutions using the present theory are compared with the solutions of other shear-deformation theories. A good agreement is achieved through these comparisons and the advantages of the present theory are clearly verified. The shear deformation plate theory presented here can be applied to the analysis of laminated composite plates to better predict their dynamic and static behaviors. The proposed theory should also be supplemented to the theory of finite element analysis for developing new shell elements.

  12. Analysis of plate spin motion and its implications for strength of plate boundary

    NASA Astrophysics Data System (ADS)

    Matsuyama, Takeshi; Iwamori, Hikaru

    2016-02-01

    In this study, we investigate the driving forces of plate motion, especially those of plate spin motion, that are related to the toroidal components of the global plate velocity field. In previous works, numerical simulations of mantle convection have been used to examine the extent to which toroidal velocity components are naturally generated on the surface, by varying key parameters, notably the rheological properties of plates and plate boundaries. Here, we take the reverse approach and perform analyses of observed plate motions, which show an increase in the toroidal/poloidal ratio at high degrees of spherical harmonic expansion, as well as a rapid change in the plate spin rate and the estimated driving stress around a critical plate size of approximately 1000 km. This quantitative relationship constrains the strength at plate boundaries to 3-75 MPa, which is consistent with several seismological observations, including those from the NE Japan arc associated with the 2011 Tohoku earthquake.

  13. Wide-Field Plate Database

    NASA Astrophysics Data System (ADS)

    Tsvetkov, M. K.; Stavrev, K. Y.; Tsvetkova, K. P.; Semkov, E. H.; Mutatov, A. S.

    The Wide-Field Plate Database (WFPDB) and the possibilities for its application as a research tool in observational astronomy are presented. Currently the WFPDB comprises the descriptive data for 400 000 archival wide field photographic plates obtained with 77 instruments, from a total of 1 850 000 photographs stored in 269 astronomical archives all over the world since the end of last century. The WFPDB is already accessible for the astronomical community, now only in batch mode through user requests sent by e-mail. We are working on on-line interactive access to the data via INTERNET from Sofia and parallel from the Centre de Donnees Astronomiques de Strasbourg. (Initial information can be found on World Wide Web homepage URL http://www.wfpa.acad.bg.) The WFPDB may be useful in studies of a variety of astronomical objects and phenomena, andespecially for long-term investigations of variable objects and for multi-wavelength research. We have analysed the data in the WFPDB in order to derive the overall characteristics of the totality of wide-field observations, such as the sky coverage, the distributions by observation time and date, by spectral band, and by object type. We have also examined the totality of wide-field observations from point of view of their quality, availability and digitisation. The usefulness of the WFPDB is demonstrated by the results of identification and investigation of the photometrical behaviour of optical analogues of gamma-ray bursts.

  14. Petrologic implications of plate tectonics.

    PubMed

    Yoder, H S

    1971-07-30

    Petrologists can make significant contributions to the plate tectonic concept. Fixing the stability fields of the principal rock types involved will provide the limits of pressure and temperature of the various environments. Experimental determination of the partition coefficients of the trace elements will be helpful. Studies of the partial melting behavior of possible parental materials in the absence and presence of water, especially the undersaturated region, will contribute to the understanding of magma production. Experimental observations on the rheological properties of the peridotites below and just above the solidus will lead to a better evaluation of the convective mechanism. Measurement of the fundamental properties of rocks, such as the density of solids and liquids at high pressures and temperatures, would contribute to understanding the concepts of diapiric rise, magma segregation, and the low-velocity zone. Broader rock sampling of the oceanic areas of all environments will do much to define the petrologic provinces. The field petrologist specializing in the Paleozoic regions and Precambrian shields can contribute by examining those regions for old plate boundaries and devising new criteria for their recognition. PMID:17770454

  15. Current global plate kinematics from GPS (1995-2007) with the plate-consistent reference frame

    NASA Astrophysics Data System (ADS)

    Kogan, Mikhail G.; Steblov, Grigory M.

    2008-04-01

    We present the vectors of rotation of 10 major lithospheric plates, estimated from continuous GPS observations at 192 globally distributed stations; 71 stations were selected as representing stable plate regions. All days for the period 1995.0-2007.0 were included in the analysis. In contrast to previous GPS plate models, our model is independent of international terrestrial reference frames (ITRF). The origin of our plate-consistent reference frame is the center of plate rotation (CP) rather than the center of mass of the entire Earth's system (CM) as in recent versions of ITRF. We estimate plate rotations and CP by minimizing the misfit between the horizontal velocities predicted by the plate model and the observed GPS velocities. If any version of ITRF is used as the reference frame, the drift of the ITRF origin relative to CP cannot be neglected in estimation of plate rotation vectors and plate-residual station velocities. The model of the plate kinematics presented here addresses the problem debated since the beginning of the space geodesy: how big are disagreements between the current plate motions and the motions averaged over several million years? We compare the vectors of relative plate rotations estimated here with the published vectors from GPS and geologic models. We also discuss the integrity of individual plates as exhibited by plate-residual station velocities. For seven largest plates, the RMS value of plate-residual station velocities in stable plate interiors is 0.5-0.9 mm/a; this value is an upper bound on deviation of real plates from infinite stiffness.

  16. Effect of plate roughness on the field near RPC plates

    NASA Astrophysics Data System (ADS)

    Jash, A.; Majumdar, N.; Mukhopadhyay, S.; Chattopadhyay, S.

    2016-06-01

    The inner surfaces of the electrodes encompassing the gas volume of a Resistive Plate Chamber (RPC) have been found to exhibit asperities with, grossly, three kind of features. The desired uniform electric field within the gas volume of RPC is expected to be affected due to the presence of these asperities, which will eventually affect the final response from the detector. In this work, an attempt has been made to model the highly complex roughness of the electrode surfaces and compute its effect on the electrostatic field within RPC gas chamber. The calculations have been performed numerically using Finite Element Method (FEM) and Boundary Element Method (BEM) and the two methods have been compared in this context.

  17. Battery plate containing filler with conductive coating

    NASA Technical Reports Server (NTRS)

    Rowlette, John J. (Inventor)

    1986-01-01

    The plate (10) comprises a matrix or binder resin phase (12) in which is dispersed particulate, conductive tin oxide such as tin oxide coated glass fibers (14). A monopolar plate (11) is prepared by coating a layer (18) of electrolytically active material onto a surface of the plate (10). Tin oxide is prevented from reduction by coating a surface of the plate (10) with a conductive, impervious layer resistant to reduction such as a thin film (22) of lead adhered to the plate with a layer (21) of conductive adhesive. The plate (10) can be formed by casting a molten dispersion from mixer (36) onto a sheet (30) of lead foil or by passing an assembly of a sheet (41) of resin, a sheet (43) of fiberglass and a sheet (45) of lead between the nip of heated rollers (48, 50).

  18. Battery plate containing filler with conductive coating

    NASA Technical Reports Server (NTRS)

    Rowlette, John J. (Inventor)

    1985-01-01

    The plate (10) comprises a matrix or binder resin phase (12) in which is dispersed particulate, conductive tin oxide such as tin oxide coated glass fibers (14). A monopolar plate (11) is prepared by coating a layer (18) of electrolytically active material onto a surface of the plate (10). Tin oxide is prevented from reduction by coating a surface of the plate (10) with a conductive, impervious layer resistant to reduction such as a thin film (22) of lead adhered to the plate with a layer (21) of conductive adhesive. The plate (10) can be formed by casting a molten dispersion from mixer (36) onto a sheet (30) of lead foil or by passing an assembly of a sheet (41) of resin, a sheet (43) of fiberglass and a sheet (45) of lead between the nip of heated rollers (48, 50).

  19. Excitation and Characterization of Chladni Plate Patterns

    NASA Astrophysics Data System (ADS)

    Bourke, Shannon; Behringer, Ernest

    2011-04-01

    When a thin metal plate with a small amount of sand on it is made to vibrate, aesthetically pleasing sand patterns can form along the nodal lines of the plate. These symmetric patterns are called Chladni Patterns. Students taking PHY 101 Physical Science in the Arts at Eastern Michigan University create these patterns by pulling a violin bow across the edge of a plate, or by using a mechanical oscillator to drive the center of a plate. These two methods only allow a small subset of all possible points on the plate to be excited. We designed and built an electronic device that allows its user to excite the plate at any point. We present patterns created with this electronic device and other methods, and describe ways to model the observed patterns.

  20. Membrane- and plate-type acoustic metamaterials.

    PubMed

    Huang, Tai-Yun; Shen, Chen; Jing, Yun

    2016-06-01

    Over the past decade there has been a great amount of research effort devoted to the topic of acoustic metamaterials (AMMs). The recent development of AMMs has enlightened the way of manipulating sound waves. Several potential applications such as low-frequency noise reduction, cloaking, angular filtering, subwavelength imaging, and energy tunneling have been proposed and implemented by the so-called membrane- or plate-type AMMs. This paper aims to offer a thorough overview on the recent development of membrane- or plate-type AMMs. The underlying mechanism of these types of AMMs for tuning the effective density will be examined first. Four different groups of membrane- or plate-type AMMs (membranes with masses attached, plates with masses attached, membranes or plates without masses attached, and active AMMs) will be reviewed. The opportunities, limitations, and challenges of membrane- or plate-type AMMs will be also discussed. PMID:27369148

  1. Rapidly Moving Divertor Plates In A Tokamak

    SciTech Connect

    S. Zweben

    2011-05-16

    It may be possible to replace conventional actively cooled tokamak divertor plates with a set of rapidly moving, passively cooled divertor plates on rails. These plates would absorb the plasma heat flux with their thermal inertia for ~10-30 sec, and would then be removed from the vessel for processing. When outside the tokamak, these plates could be cooled, cleaned, recoated, inspected, and then returned to the vessel in an automated loop. This scheme could provide nearoptimal divertor surfaces at all times, and avoid the need to stop machine operation for repair of damaged or eroded plates. We describe various possible divertor plate designs and access geometries, and discuss an initial design for a movable and removable divertor module for NSTX-U.

  2. Coupling between plate vibration and acoustic radiation

    NASA Technical Reports Server (NTRS)

    Frendi, Abdelkader; Maestrello, Lucio; Bayliss, Alvin

    1992-01-01

    A detailed numerical investigation of the coupling between the vibration of a flexible plate and the acoustic radiation is performed. The nonlinear Euler equations are used to describe the acoustic fluid while the nonlinear plate equation is used to describe the plate vibration. Linear, nonlinear, and quasi-periodic or chaotic vibrations and the resultant acoustic radiation are analyzed. We find that for the linear plate response, acoustic coupling is negligible. However, for the nonlinear and chaotic responses, acoustic coupling has a significant effect on the vibration level as the loading increases. The radiated pressure from a plate undergoing nonlinear or chaotic vibrations is found to propagate nonlinearly into the far-field. However, the nonlinearity due to wave propagation is much weaker than that due to the plate vibrations. As the acoustic wave propagates into the far-field, the relative difference in level between the fundamental and its harmonics and subharmonics decreases with distance.

  3. Real time monitoring of electroless nickel plating

    NASA Astrophysics Data System (ADS)

    Rains, Aaron E.; Kline, Ronald A.

    2013-01-01

    This work deals with the design and manufacturing of the heat and chemical resistant transducer case required for on-line immersion testing, experimental design, data acquisition and signal processing. Results are presented for several depositions with an accuracy of two ten-thousandths of an inch in coating thickness obtained. Monitoring the deposition rate of Electroless Nickel (EN) plating in-situ will provide measurement of the accurate dimensions of the component being plated, in real time. EN is used as for corrosion and wear protection for automotive an - Electroless Nickel (EN) plating is commonly used for corrosion and wear protection for automotive and aerospace components. It plates evenly and symmetrically, theoretically allowing the part to be plated to its final dimension. Currently the standard approach to monitoring the thickness of the deposited nickel is to remove the component from the plating bath and physically measure the part. This can lead to plating problems such as pitting, non-adhesion of the deposit and contamination of the plating solution. The goal of this research effort is to demonstrate that plating thickness can be rapidly and accurately measured using ultrasonic testing. Here a special housing is designed to allow immersion of the ultrasonic transducers directly into the plating bath. An FFT based signal processing algorithm was developed to resolve closely spaced echoes for precise thickness determination. The technique in this research effort was found to be capable of measuring plating thicknesses to within 0.0002 inches. It is expected that this approach will lead to cost savings in many EN plating operations.

  4. High speed thin plate fatigue crack monitor

    NASA Technical Reports Server (NTRS)

    Wincheski, Buzz A. (Inventor); Heyman, Joseph S. (Inventor); Namkung, Min (Inventor); Fulton, James P. (Inventor)

    1996-01-01

    A device and method are provided which non-destructively detect crack length and crack geometry in thin metallic plates. A non-contacting vibration apparatus produces resonant vibrations without introducing extraneous noise. Resulting resonant vibration shifts in cracked plates are correlated to known crack length in plates with similar resonant vibration shifts. In addition, acoustic emissions of cracks at resonance frequencies are correlated to acoustic emissions from known crack geometries.

  5. Avionics Box Cold Plate Damage Prevention

    NASA Technical Reports Server (NTRS)

    Stambolian, Damon; Larcher, Steven; Henderson, Gena; Tran, Donald

    2011-01-01

    Over the years there have been several occurrences of damage to Space Shuttle Orbiter cold plates during removal and replacement of avionics boxes. Thus a process improvement team was put together to determine ways to prevent these kinds of damage. From this effort there were many solutions including, protective covers, training, and improved operations instructions. The focus of this paper is to explain the cold plate damage problem and the corrective actions for preventing future damage to aerospace avionics cold plate designs.

  6. Anisotropic magnetocapacitance in ferromagnetic-plate capacitors

    NASA Astrophysics Data System (ADS)

    Haigh, J. A.; Ciccarelli, C.; Betz, A. C.; Irvine, A.; Novák, V.; Jungwirth, T.; Wunderlich, J.

    2015-04-01

    The capacitance of a parallel-plate capacitor can depend on the applied magnetic field. Previous studies have identified capacitance changes induced via classical Lorentz force or spin-dependent Zeeman effects. Here we measure a magnetization direction-dependent capacitance in parallel-plate capacitors where one plate is a ferromagnetic semiconductor, gallium manganese arsenide. This anisotropic magnetocapacitance is due to the anisotropy in the density of states dependent on the magnetization through the strong spin-orbit interaction.

  7. Bipolar plates for PEM fuel cells

    NASA Astrophysics Data System (ADS)

    Middelman, E.; Kout, W.; Vogelaar, B.; Lenssen, J.; de Waal, E.

    The bipolar plates are in weight and volume the major part of the PEM fuel cell stack, and are also a significant contributor to the stack costs. The bipolar plate is therefore a key component if power density has to increase and costs must come down. Three cell plate technologies are expected to reach targeted cost price levels, all having specific advantages and drawbacks. NedStack has developed a conductive composite materials and a production process for fuel cell plates (bipolar and mono-polar). The material has a high electric and thermal conductivity, and can be processed into bipolar plates by a proprietary molding process. Process cycle time has been reduced to less than 10 s, making the material and process suitable for economical mass production. Other development work to increase material efficiency resulted in thin bipolar plates with integrated cooling channels, and integrated seals, and in two-component bipolar plates. Total thickness of the bipolar plates is now less than 3 mm, and will be reduced to 2 mm in the near future. With these thin integrated plates it is possible to increase power density up to 2 kW/l and 2 kW/kg, while at the same time reducing cost by integrating other functions and less material use.

  8. Plate Tectonics: A Paradigm under Threat.

    ERIC Educational Resources Information Center

    Pratt, David

    2000-01-01

    Discusses the challenges confronting plate tectonics. Presents evidence that contradicts continental drift, seafloor spreading, and subduction. Reviews problems posed by vertical tectonic movements. (Contains 242 references.) (DDR)

  9. Vibration of thin, tensioned, helically wrapped plates

    NASA Astrophysics Data System (ADS)

    Lopez, Ernesto; Müftü, Sinan

    2011-02-01

    Free vibration analysis of a thin tensioned plate, wrapped around a cylindrical guide in a helical manner is presented. The system is a model of a thin, flexible web wrapped around a turn-bar. The equation of motion of the wrapped plate is derived by using the energy method and with the Kirchhoff-Love assumptions. The weak form of the equation of motion was obtained by the finite element method and the eigenvalue problem was solved numerically. The effects of parameters such as plate tension, guide radius, longitudinal and helical wrap angles, plate width, and the lengths of the non-wrapped segments were investigated. Eigenmodes with same mode numbers were observed in symmetric and anti-symmetric fashion about the center of the plate, for symmetrically wrapped plates. It was shown that the plate/shell boundary of the wrapped plate effectively acts like a support. For non-helically wrapped plates the free edges cause a frequency clustering of the lateral modes about the dominant longitudinal mode. The frequency clustering diminishes when helical wrap is introduced.

  10. The floor plate: multiple cells, multiple signals.

    PubMed

    Placzek, Marysia; Briscoe, James

    2005-03-01

    One of the key organizers in the CNS is the floor plate - a group of cells that is responsible for instructing neural cells to acquire distinctive fates, and that has an important role in establishing the elaborate neuronal networks that underlie the function of the brain and spinal cord. In recent years, considerable controversy has arisen over the mechanism by which floor plate cells form. Here, we describe recent evidence that indicates that discrete populations of floor plate cells, with characteristic molecular properties, form in different regions of the neuraxis, and we discuss data that imply that the mode of floor plate induction varies along the anteroposterior axis. PMID:15738958

  11. Dynamic stiffness formulation for free orthotropic plates

    NASA Astrophysics Data System (ADS)

    Ghorbel, O.; Casimir, J. B.; Hammami, L.; Tawfiq, I.; Haddar, M.

    2015-06-01

    This paper presents a procedure for developing the dynamic stiffness matrix of a free orthotropic Kirchhoff plate. The dynamic stiffness matrix is computed for free edge boundary conditions of the plate that allow assembly procedures. The method is based on a strong formulation of Kirchhoff plate equations and series solutions, taking advantage of the symmetry and Gorman type decomposition of the free boundary conditions. The performances of the so-called Dynamic Stiffness Method (DSM) are evaluated by comparing the harmonic responses of an orthotropic Kirchhoff plate with those obtained from the Finite Element Method using four noded quadrilateral elements.

  12. Locomotion of a flapping flexible plate

    NASA Astrophysics Data System (ADS)

    Hua, Ru-Nan; Zhu, Luoding; Lu, Xi-Yun

    2013-12-01

    The locomotion of a flapping flexible plate in a viscous incompressible stationary fluid is numerically studied by an immersed boundary-lattice Boltzmann method for the fluid and a finite element method for the plate. When the leading-edge of the flexible plate is forced to heave sinusoidally, the entire plate starts to move freely as a result of the fluid-structure interaction. Mechanisms underlying the dynamics of the plate are elucidated. Three distinct states of the plate motion are identified and can be described as forward, backward, and irregular. Which state to occur depends mainly on the heaving amplitude and the bending rigidity of the plate. In the forward motion regime, analysis of the dynamic behaviors of the flapping flexible plate indicates that a suitable degree of flexibility can improve the propulsive performance. Moreover, there exist two kinds of vortex streets in the downstream of the plate which are normal and deflected wake. Further the forward motion is compared with the flapping-based locomotion of swimming and flying animals. The results obtained in the present study are found to be consistent with the relevant observations and measurements and can provide some physical insights into the understanding of the propulsive mechanisms of swimming and flying animals.

  13. Rapidly solidified metal coatings by peen plating

    NASA Technical Reports Server (NTRS)

    Chu, H. P.

    1987-01-01

    Specimens of 7075-T6 aluminum alloy were peen plated with rapidly solidified tin-lead and aluminum powders, and the cross-sections of the coated specimens were examined by light and electron microscopy. The properties of the peen plated specimens were also compared with those of shot peened specimens without any coating. It is found that peen plating with rapidly solidified metals improves the fatigue properties of the coated samples to a greater extent than shot peening alone. Specimens of 7075-T6 alloy peen plated with rapidly solidified tin-lead and aluminum exhibited better fatigue resistance than shot peened specimens in both air and salt water.

  14. MACMA: a Virtual Lab for Plate Tectonics

    NASA Astrophysics Data System (ADS)

    Grigne, C.; Combes, M.; Tisseau, C.

    2013-12-01

    MACMA (Multi-Agent Convective MAntle) is a tool developed to simulate evolutive plate tectonics and mantle convection in a 2-D cylindrical geometry (Combes et al., 2012). The model relies mainly on a force balance to compute the velocity of each plate, and on empirical rules to determine how plate boundaries move and evolve. It includes first-order features of plate tectonics: (a) all plates on Earth do not have the same size, (b) subduction zones are asymmetric, (c) plates driven by subducting slabs and upper plates do not exhibit the same velocities, and (d) plate boundaries are mobile, can collide, merge and disappear, and new plate boundaries can be created. The MACMA interface was designed to be user-friendly and a simple use of the simulator can be achieved without any prerequisite knowledge in fluid dynamics, mantle rheology, nor in numerical methods. As a preliminary study, the simulator was used by a few students from bachelor's degree to master's degree levels. An initial configuration for plate tectonics has to be created before starting a simulation: the number and types of plate boundaries (ridge, subduction, passive margins) has to be defined and seafloor ages must be given. A simple but interesting exercise consists in letting students build such an initial configuration: they must analyze a map of tectonic plates, choose a 2-D section and examine carefully a map of seafloor ages. Students mentioned that the exercise made them realize that the 3-D spherical structure of plate tectonics does not translate directly in a simple 2-D section, as opposed to what is usually shown in books. Physical parameters: e.g. mantle viscosity, number of layers to consider in the mantle (upper and lower mantle, possible asthenosphere), initial time and mantle temperature, have to be chosen, and students can use this virtual lab to see how different scenarios emerge when parameters are varied. Very importantly, the direct visualization of the mobility of plate

  15. Fuel cell cooler-humidifier plate

    DOEpatents

    Vitale, Nicholas G.; Jones, Daniel O.

    2000-01-01

    A cooler-humidifier plate for use in a proton exchange membrane (PEM) fuel cell stack assembly is provided. The cooler-humidifier plate combines functions of cooling and humidification within the fuel cell stack assembly, thereby providing a more compact structure, simpler manifolding, and reduced reject heat from the fuel cell. Coolant on the cooler side of the plate removes heat generated within the fuel cell assembly. Heat is also removed by the humidifier side of the plate for use in evaporating the humidification water. On the humidifier side of the plate, evaporating water humidifies reactant gas flowing over a moistened wick. After exiting the humidifier side of the plate, humidified reactant gas provides needed moisture to the proton exchange membranes used in the fuel cell stack assembly. The invention also provides a fuel cell plate that maximizes structural support within the fuel cell by ensuring that the ribs that form the boundaries of channels on one side of the plate have ends at locations that substantially correspond to the locations of ribs on the opposite side of the plate.

  16. Wave propagation in metamaterial lattice sandwich plates

    NASA Astrophysics Data System (ADS)

    Fang, Xin; Wen, Jihong; Yin, Jianfei; Yu, Dianlong

    2016-04-01

    This paper designed a special acoustic metamaterial 3D Kagome lattice sandwich plate. Dispersion properties and vibration responses of both traditional plate and metamaterial plate are investigated based on FEA methods. The traditional plate does not have low-frequency complete bandgaps, but the metamaterial plate has low-frequency complete bandgap (at 620Hz) coming from the symmetrical local cantilever resonators. The bandgap frequency is approximate to the first-order natural frequency of the oscillator. Complex wave modes are analyzed. The dispersion curves of longitudinal waves exist in the flexural bandgap. The dispersion properties demonstrate the metamaterial design is advantageous to suppress the low-frequency flexural wave propagation in lattice sandwich plate. The flexural vibrations near the bandgap are also suppressed efficiently. The longitudinal excitation stimulates mainly longitudinal waves and lots of low-frequency flexural vibration modes are avoided. Furthermore, the free edge effects in metamaterial plate provide new method for damping optimizations. The influences of damping on vibrations of the metamaterial sandwich plate are studied. Damping has global influence on the wave propagation; stronger damping will induce more vibration attenuation. The results enlighten us damping and metamaterial design approaches can be unite in the sandwich plates to suppress the wave propagations.

  17. Modal interaction in postbuckled plates. Theory

    NASA Technical Reports Server (NTRS)

    Thurston, Gaylen A.

    1989-01-01

    Plates can have more than one buckled solution for a fixed set of boundary conditions. The theory for the identification and the computation of multiple solutions in buckled plates is examined. The theory predicts modal interaction (which is also called change in buckle pattern or secondary buckling) in experiments on certain plates with multiple theoretical solutions. A set of coordinate functions is defined for Galerkin's method so that the von Karman plate equations are reduced to a coupled set of cubic equations in generalized coordinates that are uncoupled in the linear terms. An iterative procedure for solving modal interaction problems is suggested based on this cubic form.

  18. Tunable surface plasmon wave plates.

    PubMed

    Djalalian-Assl, Amir; Cadusch, Jasper J; Balaur, Eugeniu; Aramesh, Morteza

    2016-07-01

    The highest resonant transmission through an array of holes perforated in metallic screens occurs when the dielectric constant of the substrate, the superstrate, and the hole are the same. Changes in the refractive index of the homogenous environment also produce the largest shift in resonances per refractive index unit. In this Letter, we first propose and apply a technique in realization of a freestanding bi-periodic array of holes perforated in a silver film. We then show both numerically and experimentally that shifts in (1,0) and (0,1) modes in response to changes in the refractive index of the surrounding dielectric provide a mechanism for realization of a miniaturized tunable quarter-wave plate that operates in an extraordinary optical transmission mode with a high throughput and a near unity state of circularly polarized light. PMID:27367123

  19. Background events in microchannel plates

    NASA Technical Reports Server (NTRS)

    Siegmund, O. H. W.; Vallerga, J.; Wargelin, B.

    1988-01-01

    Measurements have been made to assess the characteristics and origins of background events in microchannel plates (MCPs). An overall background rate of about 0.4 events/sq cm persec has been achieved consistently for MCPs that have been baked and scrubbed. The temperature and gain of the MCPs are found to have no significant effect on the background rate. Detection of 1.46-MeV gamma rays from the MCP glass confirms the presence of K-40, with a concentration of 0.0007 percent, in MCP glass. It is shown that beta decay from K-40 is sufficient to cause the background rate and spectrum observed. Anticoincidence measurements indicate the the background rate caused by cosmic ray interactions is small (less than 0.016 events/sq cm per sec).

  20. A Treatise on Equivalent-Plate Stiffnesses for Stiffened Laminated-Composite Plates and Plate-Like Lattices

    NASA Technical Reports Server (NTRS)

    Nemeth, Michael P.

    2011-01-01

    A survey of studies conducted since 1914 on the use of equivalent-plate stiffnesses in modeling the overall, stiffness-critical response of stiffened plates and shells is presented. Two detailed, comprehensive derivations of first-approximation equivalent-plate stiffnesses are also presented that are based on the Reissner-Mindlin-type, first-order transverse-shear deformation theory for anisotropic plates. Equivalent-plate stiffness expressions, and a corresponding symbolic manipulation computer program, are also presented for several different stiffener configurations. These expressions are very general and exhibit the full range of anisotropies permitted by the Reissner-Mindlin-type, first-order transverse-shear deformation theory for anisotropic plates. The expressions presented in the present study were also compared with available, previously published results. For the most part, the previously published results are for special cases of the general expressions presented herein and are almost in complete agreement. Analysis is also presented that extends the use of the equivalent-plate stiffness expressions to sandwich plates.

  1. Thickness dependence of the Casimir force between a magnetodielectric plate and a diamagnetic plate

    SciTech Connect

    Inui, Norio

    2011-11-15

    This paper examines the repulsive Casimir force between a magnetodielectric plate, with static permeability greater than static permittivity, and a diamagnetic plate. As the thickness of the magnetodielectric plate is decreased, the attractive component of the Casimir force decreases more than the repulsive one. This effect makes the net Casimir force repulsive, and a larger repulsive Casimir force is generated compared to the Casimir force between the plates with infinite thickness.

  2. Evaluation of brush plated alloys as substitutes for tank plated hard chromium

    SciTech Connect

    Durham, H.B.; Hooper, A.M.

    1995-11-01

    This paper summarizes results obtained from a test program conducted in cooperation with Tinker Air Force Base (TAFB) in 1993 for the purpose of evaluating the potential of using brush plated alloys as replacements for tank plated hard chromium which is used in the overhaul of jet engines. Tank plating is energy expensive and generates waste products in several of the plating steps. Test specimens used in this study were fabricated from carbon steel, chromium-based stainless steel, and nickel-based stainless steel. Baseline specimens were tank plated with hard chromium or with a soft nickel capped with hard chromium. The specimens were tested for fatigue, thickness, microhardness, Taber wear, and Falex pin and vee block wear. All test were conducted in accordance with standard procedures of the American Society for Testing and Materials (ASTM). Test results obtained from the baseline specimens were compared with those obtained from specimens which had been coated with the three brush plated layered alloy solutions used in this evaluation. Results of this study show that brush plated alloy coatings appear promising as alternatives to tank plated hard chromium. Some data quality problems were encountered during testing, so at this time, definitive statements concerning the use of brush plating alloys as an acceptable alternative to tank plated hard chromium in critical TAFB maintenance, cannot be made. Although these tests results are not positive for TAFB`s operation, users of hard chromium tank plating with less critical applications may find brush plated coatings a suitable alternative. 1 ref.

  3. Simulation of Evolutive Plate Tectonics: the Size of Plates Depends on Mantle Temperature

    NASA Astrophysics Data System (ADS)

    Grigne, C.; Combes, M.

    2013-12-01

    We use a dynamic model of plate tectonics based on a multiagent approach, in a 2D cylindrical geometry (Combes et al., 2012), to study how evolutive plate tectonics affect the long term thermal state of the mantle, and in return, to analyze the relationship between the mantle mean temperature and the geometry of plate tectonics. Our model accounts for first-order features of plate tectonics: (a) all plates on Earth do not have the same size, (b) subduction zones are asymmetric, (c) plates driven by subducting slabs and upper plates do not exhibit the same velocities, and (d) plate boundaries are mobile, can collide, merge and disappear, and new plate boundaries can be created. We show that when processes for plate boundary creation (subduction initiation and ridge creation) are relying on a brittle criterion, namely when a fixed yield strength has to be reached, the average size of plates adapts to the mantle thermal state: longer plates are obtained for a hotter mantle, which implies a maximum seafloor age that remains fairly high throughout Earth's thermal history and limits mantle heat loss. This is consistent with petrological and geochemical constraints on Earth's cooling history. Important fluctuations in the mantle heat flux and velocities of plates are obtained on a timescale of a few hundred Myr, but on the long term, the relationship between the average wavelength of plate tectonics and mantle temperature can be explained by a simple scaling law. Recent compilations of geological records infer that passive margins had longer lifespans in the past (e.g. Bradley 2008; 2011), which has been linked to 'sluggish' plate tectonics and slow plates in the Precambrian (Korenaga, 2006). Our simulations outputs include lifespans of tectonic entities such as passive margins, as well as statistical data about events of plates reorganizations. We obtain faster plates in the past than at present day, but counterintuitively we also observe a low episodicity of tectonic

  4. Vacuum fusion bonding of glass plates

    DOEpatents

    Swierkowski, Steve P.; Davidson, James C.; Balch, Joseph W.

    2000-01-01

    An improved apparatus and method for vacuum fusion bonding of large, patterned glass plates. One or both glass plates are patterned with etched features such as microstructure capillaries and a vacuum pumpout moat, with one plate having at least one hole therethrough for communication with a vacuum pumpout fixture. High accuracy alignment of the plates is accomplished by a temporary clamping fixture until the start of the fusion bonding heat cycle. A complete, void-free fusion bond of seamless, full-strength quality is obtained through the plates; because the glass is heated well into its softening point and because of a large, distributed force that is developed that presses the two plates together from the difference in pressure between the furnace ambient (high pressure) and the channeling and microstructures in the plates (low pressure) due to the vacuum drawn. The apparatus and method may be used to fabricate microcapillary arrays for chemical electrophoresis; for example, any apparatus using a network of microfluidic channels embedded between plates of glass or similar moderate melting point substrates with a gradual softening point curve, or for assembly of glass-based substrates onto larger substrates, such as in flat panel display systems.

  5. Vacuum fusion bonding of glass plates

    DOEpatents

    Swierkowski, Steve P.; Davidson, James C.; Balch, Joseph W.

    2001-01-01

    An improved apparatus and method for vacuum fusion bonding of large, patterned glass plates. One or both glass plates are patterned with etched features such as microstructure capillaries and a vacuum pumpout moat, with one plate having at least one hole therethrough for communication with a vacuum pumpout fixture. High accuracy alignment of the plates is accomplished by a temporary clamping fixture until the start of the fusion bonding heat cycle. A complete, void-free fusion bond of seamless, full-strength quality is obtained through the plates; because the glass is heated well into its softening point and because of a large, distributed force that is developed that presses the two plates together from the difference in pressure between the furnace ambient (high pressure) and the channeling and microstructures in the plates (low pressure) due to the vacuum drawn. The apparatus and method may be used to fabricate microcapillary arrays for chemical electrophoresis; for example, any apparatus using a network of microfluidic channels embedded between plates of glass or similar moderate melting point substrates with a gradual softening point curve, or for assembly of glass-based substrates onto larger substrates, such as in flat panel display systems.

  6. Spiral Plate Method for Bacterial Determination

    PubMed Central

    Gilchrist, J. E.; Campbell, J. E.; Donnelly, C. B.; Peeler, J. T.; Delaney, J. M.

    1973-01-01

    A method is described for determining the number of bacteria in a solution by the use of a machine which deposits a known volume of sample on a rotating agar plate in an ever decreasing amount in the form of an Archimedes spiral. After the sample is incubated, different colony densities are apparent on the surface of the plate. A modified counting grid is described which relates area of the plate of volume of sample. By counting an appropriate area of the plate, the number of bacteria in the sample is estimated. This method was compared to the pour plate procedure with the use of pure and mixed cultures in water and milk. The results did not demonstrate a significant difference in variance between duplicates at the α = 0.01 level when concentrations of 600 to 12 × 105 bacteria per ml were used, but the spiral plate method gave counts that were higher than counts obtained by the pour plate method. The time and materials required for this method are substantially less than those required for the conventional aerobic pour plate procedure. Images PMID:4632851

  7. Pressure-Letdown Plates for Coal Gasifiers

    NASA Technical Reports Server (NTRS)

    Collins, E. R., Jr.

    1985-01-01

    Variation of pseudoporous plates used with coal gasifiers in pressure letdown stage of processing minimize clogging. Rotating plates containing variable gap annuli continually change flow path to enable erosionless reduction of gas pressure. Particles that otherwise clog porous plugs pass through gaps.

  8. Computing relative plate velocities: a primer

    SciTech Connect

    Bevis, M.

    1987-08-01

    Standard models of present-day plate motions are framed in terms of rates and poles of rotation, in accordance with the well-known theorem due to Euler. This article shows how computation of relative plate velocities from such models can be viewed as a simple problem in spherical trigonometry. A FORTRAN subroutine is provided to perform the necessary computations.

  9. Plate Tectonic Cycle. K-6 Science Curriculum.

    ERIC Educational Resources Information Center

    Blueford, J. R.; And Others

    Plate Tectonics Cycle is one of the units of a K-6 unified science curriculum program. The unit consists of four organizing sub-themes: (1) volcanoes (covering formation, distribution, and major volcanic groups); (2) earthquakes (with investigations on wave movements, seismograms and sub-suface earth currents); (3) plate tectonics (providing maps…

  10. 49 CFR 236.779 - Plate, top.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Plate, top. 236.779 Section 236.779 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF... OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Definitions § 236.779 Plate, top....

  11. 49 CFR 236.779 - Plate, top.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Plate, top. 236.779 Section 236.779 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF... OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Definitions § 236.779 Plate, top....

  12. 49 CFR 236.779 - Plate, top.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Plate, top. 236.779 Section 236.779 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF... OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Definitions § 236.779 Plate, top....

  13. 49 CFR 236.779 - Plate, top.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Plate, top. 236.779 Section 236.779 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF... OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Definitions § 236.779 Plate, top....

  14. 49 CFR 236.779 - Plate, top.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Plate, top. 236.779 Section 236.779 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF... OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Definitions § 236.779 Plate, top....

  15. Improved nickel plating of Inconel X-750

    NASA Technical Reports Server (NTRS)

    Farmer, M. E.; Feeney, J. E.; Kuster, C. A.

    1969-01-01

    Electroplating technique with acid pickling provides a method of applying nickel plating on Inconel X-750 tubing to serve as a wetting agent during brazing. Low-stress nickel-plating bath contains no organic wetting agents that cause the nickel to blister at high temperatures.

  16. 30 CFR 22.10 - Approval plate.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... MINING PRODUCTS PORTABLE METHANE DETECTORS § 22.10 Approval plate. (a) Attachment to be made by manufacturers. (1) Manufacturers shall attach, stamp, or mold an approval plate on each permissible methane... follows: Permissible Methane Detector (or Permissible Methane Indicating Detector) Approval No. ___...

  17. Layered Plating Specimens For Mechanical Tests

    NASA Technical Reports Server (NTRS)

    Thompson, Linda B.; Flowers, Cecil E.

    1991-01-01

    Layered specimens readily made in standard sizes for tensile and other tests of mechanical properties. Standard specimen of metal ordinarily difficult to plate to standard grip thickness or diameter made by augmentation with easier-to-plate material followed by machining to standard size and shape.

  18. 49 CFR 213.123 - Tie plates.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Tie plates. 213.123 Section 213.123 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION TRACK SAFETY STANDARDS Track Structure § 213.123 Tie plates. (a) In Classes 3 through 5...

  19. 49 CFR 213.123 - Tie plates.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Tie plates. 213.123 Section 213.123 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION TRACK SAFETY STANDARDS Track Structure § 213.123 Tie plates. (a) In Classes 3 through 5...

  20. 49 CFR 213.123 - Tie plates.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Tie plates. 213.123 Section 213.123 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION TRACK SAFETY STANDARDS Track Structure § 213.123 Tie plates. (a) In Classes 3 through 5...

  1. 49 CFR 213.123 - Tie plates.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Tie plates. 213.123 Section 213.123 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION TRACK SAFETY STANDARDS Track Structure § 213.123 Tie plates. (a) In Classes 3 through 5...

  2. Cycloid kinematics of relative plate motion

    SciTech Connect

    Cronin, V.S.

    1987-11-01

    The trajectory of a point on one plate as observed from another plate is generally a complex curve and not a small circle around a single axis of relative motion, as is commonly assumed. The shape of the relative-motion path is given the general name spherical cycloid because of its morphological similarity to cycloid planetary trajectories described by early astronomers. The cycloid relative-motion model predicts that the following phenomena occur during finite displacements: (1) the relative velocity and the curvature of the trajectory of a point on one plate relative to another plate varies systematically; (2) plates wobble relative to one another; and (3) the angle of convergence and/or divergence varies systematically along the length of any given transform fault. The small-circle relative-motion model, whereby transform faults have been considered lines of pure slip along which crust is conserved, is not generally valid for finite relative displacements.

  3. Shock wave absorber having apertured plate

    DOEpatents

    Shin, Yong W.; Wiedermann, Arne H.; Ockert, Carl E.

    1985-01-01

    The shock or energy absorber disclosed herein utilizes an apertured plate maintained under the normal level of liquid flowing in a piping system and disposed between the normal liquid flow path and a cavity pressurized with a compressible gas. The degree of openness (or porosity) of the plate is between 0.01 and 0.60. The energy level of a shock wave travelling down the piping system thus is dissipated by some of the liquid being jetted through the apertured plate toward the cavity. The cavity is large compared to the quantity of liquid jetted through the apertured plate, so there is little change in its volume. The porosity of the apertured plate influences the percentage of energy absorbed.

  4. Shock wave absorber having apertured plate

    DOEpatents

    Shin, Y.W.; Wiedermann, A.H.; Ockert, C.E.

    1983-08-26

    The shock or energy absorber disclosed herein utilizes an apertured plate maintained under the normal level of liquid flowing in a piping system and disposed between the normal liquid flow path and a cavity pressurized with a compressible gas. The degree of openness (or porosity) of the plate is between 0.01 and 0.60. The energy level of a shock wave travelling down the piping system thus is dissipated by some of the liquid being jetted through the apertured plate toward the cavity. The cavity is large compared to the quantity of liquid jetted through the apertured plate, so there is little change in its volume. The porosity of the apertured plate influences the percentage of energy absorbed.

  5. Torsion and transverse bending of cantilever plates

    NASA Technical Reports Server (NTRS)

    Reissner, Eric; Stein, Manuel

    1951-01-01

    The problem of combined bending and torsion of cantilever plates of variable thickness, such as might be considered for solid thin high-speed airplane or missile wings, is considered in this paper. The deflections of the plate are assumed to vary linearly across the chord; minimization of the potential energy by means of the calculus of variations then leads to two ordinary linear differential equations for the bending deflections and the twist of the plate. Because the cantilever is analyzed as a plate rather than as a beam, the effect of constraint against axial warping in torsion is inherently included. The application of this method to specific problems involving static deflection, vibration, and buckling of cantilever plates is presented. In the static-deflection problems, taper and sweep are considered.

  6. Optimum design of geodesically stiffened composite plates

    NASA Technical Reports Server (NTRS)

    Guerdal, Zafer; Phillips, John L.

    1988-01-01

    With the goal of tailorability in mind, the in-plane stiffness characteristics of a particular grid stiffened plate configuration under axial and shear loads have been studied. The contribution of the skin to the stiffener network and the resultant skin/rib interaction is analyzed. For the given plate geometry and loads, it is shown that an optimum configuration does exist. To achieve optimally designed practical plate configurations, buckling constraints need to be included in the design. Due to the complex geometry and loading of the plates, a simplified local buckling analysis of isolated stiffeners and triangular skin elements between the stiffeners is considered. Development of a stiffener buckling analysis represent stiffeners as shear deformable plate elements is presented.

  7. Is There Really A North American Plate?

    NASA Astrophysics Data System (ADS)

    Krill, A.

    2011-12-01

    Lithospheric plates are typically identified from earthquake epicenters and evidence such as GPS movements. But no evidence indicates a plate boundary between the North American and South American Plates. Some plate maps show them separated by a transform boundary, but it is only a fracture zone. Other maps show an "undefined plate boundary" or put no boundary between these two plates (check Google images). Early plate maps showed a single large American Plate, quite narrow east of the Caribbean Plate (Le Pichon 1968, Morgan 1968). The North and South American Plates became established by the leading textbook Earth (Press & Siever 1974). On their map, from a Scientific American article by John Dewey (1972), these new plates were separated by an "uncertain plate boundary." The reasons for postulating a North American Plate were probably more psychological than geological. Each of the other continents of the world had its own plate, and North American geologists naturally wanted theirs. Similarly, European geographers used to view Europe as its own continent. A single large plate should again be hypothesized. But the term American Plate would now be ambiguous ("Which plate, North or South?") Perhaps future textbook authors could call it the "Two-American Plate." Textbook authors ultimately decide such global-tectonic matters. I became aware of textbook authors' opinions and influence from my research into the history of Alfred Wegener's continental drift (see Fixists vs. Mobilists by Krill 2011). Leading textbook author Charles Schuchert realized that continental drift would abolish his cherished paleogeographic models of large east-west continents (Eria, Gondwana) and small oceans (Poseiden, Nereis). He and his junior coauthors conspired to keep drift evidence out of their textbooks, from the 1934-editions until the 1969-editions (Physical Geology by Longwell et al. 1969, Historical Geology by Dunbar & Waage 1969). Their textbooks ruled in America. Textbooks

  8. Holographic NDT of thin titanium plate described

    NASA Astrophysics Data System (ADS)

    Yang, R.

    1986-01-01

    Holography is a technique for recording the amplitude and phase changes of an object on a photographic plate in the form of interference fringes. Because the holographic interference method can examine a component in the noncontact mode and is not bothered by complicated part shape or surface roughness, it has been widely used in nondestructive testing. In the rapidly developing aerospace industry, titanium and titanium alloy thin plates are used more and more but local delamination has been found in the production process of bonded titanium plates. Using ultrasonic methods, such defects are difficult to detect and large area delaminations with tightly closed edges can easily be missed. Other testing methods are also unsuccessful. A holographic method was developed for detecting defects in thin titanium plates and several high temperature alloy plates were tested. The testing equipment, methods and results are discussed.

  9. Volcanism in response to plate flexure.

    PubMed

    Hirano, Naoto; Takahashi, Eiichi; Yamamoto, Junji; Abe, Natsue; Ingle, Stephanie P; Kaneoka, Ichiro; Hirata, Takafumi; Kimura, Jun-Ichi; Ishii, Teruaki; Ogawa, Yujiro; Machida, Shiki; Suyehiro, Kiyoshi

    2006-09-01

    Volcanism on Earth is known to occur in three tectonic settings: divergent plate boundaries (such as mid-ocean ridges), convergent plate boundaries (such as island arcs), and hot spots. We report volcanism on the 135 million-year-old Pacific Plate not belonging to any of these categories. Small alkalic volcanoes form from small percent melts and originate in the asthenosphere, as implied by their trace element geochemistry and noble gas isotopic compositions. We propose that these small volcanoes erupt along lithospheric fractures in response to plate flexure during subduction. Minor extents of asthenospheric melting and the volcanoes' tectonic alignment and age progression in the direction opposite to that of plate motion provide evidence for the presence of a small percent melt in the asthenosphere. PMID:16873612

  10. Tectonic Evolution of the Jurassic Pacific Plate

    NASA Astrophysics Data System (ADS)

    Nakanishi, M.; Ishihara, T.

    2015-12-01

    We present the tectonic evolution of the Jurassic Pacific plate based on magnetic anomly lineations and abyssal hills. The Pacific plate is the largest oceanic plate on Earth. It was born as a microplate aroud the Izanagi-Farallon-Phoenix triple junction about 192 Ma, Early Jurassic [Nakanishi et al., 1992]. The size of the Pacific plate at 190 Ma was nearly half that of the present Easter or Juan Fernandez microplates in the East Pacific Rise [Martinez et at, 1991; Larson et al., 1992]. The plate boundary surrounding the Pacific plate from Early Jurassic to Early Cretaceous involved the four triple junctions among Pacific, Izanagi, Farallon, and Phoenix plates. The major tectonic events as the formation of oceanic plateaus and microplates during the period occurred in the vicinity of the triple junctions [e.g., Nakanishi and Winterer, 1998; Nakanishi et al., 1999], implying that the study of the triple junctions is indispensable for understanding the tectonic evolution of the Pacific plate. Previous studies indicate instability of the configuration of the triple junctions from Late Jurassic to Early Cretaceous (155-125 Ma). On the other hand, the age of the birth of the Pacific plate was determined assuming that all triple junctions had kept their configurations for about 30 m.y. [Nakanishi et al., 1992] because of insufficient information of the tectonic history of the Pacific plate before Late Jurassic.Increase in the bathymetric and geomagnetic data over the past two decades enables us to reveal the tectonic evolution of the Pacific-Izanagi-Farallon triple junction before Late Jurassic. Our detailed identication of magnetic anomaly lineations exposes magnetic bights before anomaly M25. We found the curved abyssal hills originated near the triple junction, which trend is parallel to magnetic anomaly lineations. These results imply that the configuration of the Pacific-Izanagi-Farallon triple junction had been RRR before Late Jurassic.

  11. Parallel Plate System for Collecting Data Used to Determine Viscosity

    NASA Technical Reports Server (NTRS)

    Kaukler, William (Inventor); Ethridge, Edwin C. (Inventor)

    2013-01-01

    A parallel-plate system collects data used to determine viscosity. A first plate is coupled to a translator so that the first plate can be moved along a first direction. A second plate has a pendulum device coupled thereto such that the second plate is suspended above and parallel to the first plate. The pendulum device constrains movement of the second plate to a second direction that is aligned with the first direction and is substantially parallel thereto. A force measuring device is coupled to the second plate for measuring force along the second direction caused by movement of the second plate.

  12. Spirit's Tracks around 'Home Plate'

    NASA Technical Reports Server (NTRS)

    2006-01-01

    [figure removed for brevity, see original site] Annotated Version

    This portion of an image acquired by the Mars Reconnaissance Orbiter's High Resolution Imaging Science Experiment camera shows the Spirit rover's winter campaign site. The rover is visible. So is the 'Low Ridge' feature where Spirit was parked with an 11-degree northerly tilt to maximize sunlight on the solar panels during the southern winter season. Tracks made by Spirit on the way to 'Home Plate' and to and from 'Tyrone,' an area of light-toned soils exposed by rover wheel motions, are also evident. The original image is catalogued as PSP_001513_1655_red and was taken Sept. 29, 2006.

    NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Mars Reconnaissance Orbiter for NASA's Science Mission Directorate, Washington. Lockheed Martin Space Systems, Denver, is the prime contractor for the project and built the spacecraft. The High Resolution Imaging Science Experiment is operated by the University of Arizona, Tucson, and the instrument was built by Ball Aerospace and Technology Corp., Boulder, Colo.

  13. The jubilee of plate tectonics

    NASA Astrophysics Data System (ADS)

    Glen, William; Frankel, Henry

    What should one expect at a birthday gathering for an idea that suffered disdain from birth, but was later transformed overnight into the ruling global theory of the Earth sciences? Tom Hilde and Richard Carlson (Texas A&M University, College Station, Tex.), under the auspices of the Texas A&M Geodynamics Research Institute, with the cooperation of the National Aeronautics and Space Administration (NASA) , the Inter-Union Commission on the Lithosphere, and the U.S. Geodynamics Committee, convened an unprecedented gathering of the makers of Earth science's modern revolution and a large number of their foremost disciples at Texas A&M April 22- 24 , 1987.Those who missed the show will have to read for weeks to learn of the panoply of profound new developments across the broad front of research bearing on plate tectonics, but those with an interest in their own intellectual genealogy will not be able to recapture the sense of historic moment that pervaded Rudder Tower Conference Center as many of the old revolutionaries opened windows on the past. Of the 20 key participants or originators who were invited to speak, all but four sent abstracts. Pleased and surprised by this strong response, the convenors found themselves in the rather difficult position of having to limit the number of talks by nonoriginators to 20. The unique assembly also provided the first opportunity to video interviews with more than a dozen of the originators.

  14. Lee plate equations for electroded quartz crystal plates with the consideration of electrode density and stiffness.

    PubMed

    Wang, Ji; Chen, Guojun; Du, Jianke

    2008-02-01

    Lee plate equations for high-frequency vibrations of piezoelectric plates have been established and improved over the last decades with the sole objective of obtaining the accurate prediction of frequency and mode shapes to aid crystal resonator design. The latest improvement includes extra terms related to derivatives of the flexural displacement to adjust the accuracy and consider electrodes for practical applications. As part of the efforts to make the equations applicable for resonator design with the improved frequency accuracy and consideration of electrodes, we derived Lee plate equations for electroded plates by changing the integration limits in the dimension reduction procedure to signify the dominant role of the crystal plate. By modifying the density terms in plate equations to include the contribution of both electrode stiffness and density, the accuracy of the thickness-shear vibration frequency of electroded plates is improved for commonly used electrode materials. PMID:18334357

  15. Reducing chromium losses from a chromium plating bath. 1987 summer intern report. Project conducted at New Dimension Plating, Hutchinson, Minnesota

    SciTech Connect

    Achman, D.

    1987-12-31

    The company employs about forty people and operates for one or two eight hour shifts with an average of 315 racks of chrome plating per eight hour day. They plate a variety of metals including copper, nickel, gold, brass and chromium. Chromium is the major metal plated and is usually the last step in plating cycle. Most parts are copper plated and then nickel plated in preparation for chrome plating. The main difference between New Dimension Plating and other plating shops is the variety of parts plated. As New Dimension Plating is a job shop, a wide range of parts such as motorcycle accessories, stove parts, and custom items are metal finished. The plating lines are manual, meaning employees dip the racks into the tanks by hand. This fact along with the fact that parts vary greatly in size and shape accounts for the significant drag-out on the chromium plating line.

  16. Shells on a Sphere: Tectonic Plate Motion and Plate Boundary Deformation

    NASA Astrophysics Data System (ADS)

    Apel, Edwin Victor, III

    Plate motion models have matured from being based only on geology and seismicity to incorporating space-based geodetic methods like GPS. I use a block modeling approach to incorporate both rigid block rotation and near-boundary elastic strain accumulation effects in a formal inversion of GPS velocities. Independent Okhotsk and Amurian microplate motions are tested using GPS velocities that constrain the plate kinematics of northeast Asia. Modeling favors scenarios with independent OKH and AMU motion, based on the application of F-test statistics. The plate-motion parameters of the independent plates are consistent with the kinematics inferred from earthquake focal mechanism solutions along their boundaries. GPS-measured velocities (15 from continuously recording stations within the stable India plate interior) geodetically constrain India plate motion, intraplate strain, and plate boundary deformation around the India plate. Dense station coverage from previously published studies allows rigorous testing of boundary parameterizations. I develop robust India plate motion parameters and see good agreement between predicted plate directions from the preferred model and the seismological data. Available GPS data in and around the Aegean region is combined and used to evaluate plate motion models, elastic plate boundary deformation and its relationship to seismogenic coupling along the Hellenic subduction zone. The A.D. 365 M ˜8.4, the A.D. 1303 M˜8 Crete suggest that portions of the plate interface must be locked. The primary focus of this study is to examine potential upper plate deformation resulting from a locked subduction interface, active hanging-wall extension, or both. I consider multiple model scenarios in an attempt to interpret the both the horizontal and vertical geodetic signals in the region and its implications for earthquake hazard assessment.

  17. Scaling of energy absorbing composite plates

    NASA Technical Reports Server (NTRS)

    Jackson, Karen; Lavoie, J. Andre; Morton, John

    1994-01-01

    The energy absorption response and crushing characteristics of geometrically scaled graphite-Kevlar epoxy composite plates were investigated. Two different trigger mechanisms including notch, and steeple geometries were incorporated into the plate specimens to initiate crushing. Sustained crushing was achieved with a new test fixture which provided lateral support to prevent global buckling. Values of specific sustained crushing stress (SSCS) were obtained which were lower than values reported for tube specimens from previously published data. Two sizes of hybrid plates were fabricated; a baseline or model plate, and a full-scale plate with inplane dimensions scaled by a factor of two. The thickness dimension of the full-scale plates was increased using two different techniques: the ply-level method in which each ply orientation in the baseline laminate stacking sequence is doubled, and the sublaminate technique in which the baseline laminate stacking sequence is repeated as a group. Results indicated that the SSCS has a small dependence on trigger mechanism geometry. However, a reduction in the SSCS of 10-25% was observed for the full-scale plates as compared with the baseline specimens, indicating a scaling effect in the crushing response.

  18. Scaling of energy absorbing composite plates

    NASA Technical Reports Server (NTRS)

    Jackson, Karen; Morton, John; Traffanstedt, Catherine; Boitnott, Richard

    1992-01-01

    The energy absorption response and crushing characteristics of geometrically scaled graphite-Kevlar epoxy composite plates were investigated. Three different trigger mechanisms including chamfer, notch, and steeple geometries were incorporated into the plate specimens to initiate crushing. Sustained crushing was achieved with a simple test fixture which provided lateral support to prevent global buckling. Values of specific sustained crushing stress (SSCS) were obtained which were comparable to values reported for tube specimens from previously published data. Two sizes of hybrid plates were fabricated; a baseline or model plate, and a full-scale plate with in-plane dimensions scaled by a factor of two. The thickness dimension of the full-scale plates was increased using two different techniques; the ply-level method in which each ply orientation in the baseline laminate stacking sequence is doubled, and the sublaminate technique in which the baseline laminate stacking sequence is repeated as a group. Results indicated that the SSCS is independent of trigger mechanism geometry. However, a reduction in the SSCS of 10-25 percent was observed for the full-scale plates as compared with the baseline specimens, indicating a scaling effect in the crushing response.

  19. One plate, two plates, a thousand plates. How crystallisation changes with large numbers of samples.

    PubMed

    Newman, Janet

    2011-09-01

    Turning commercial lab automation into a high-throughput centre requires an underlying process, and implementing checks to ensure that the process is working as it should. At the Collaborative Crystallisation Centre (C3), protein samples from local, national and international groups are set up in crystallisation screening and optimisation experiments with two thousand 96 well plates being set up each year. During its five years of operation, the C3 has implemented a series of enabling protocols - from simple 'reality checks' to determine if a screen has evaporated during storage to more sophisticated systems such as a sample labelling and tracking system. The most important - and perhaps surprising - lesson has been how much effort is required to effectively communicate between the centre and its clients, as well as between the centre's staff members. It is easy to confuse the concept of 'high throughput' in any field with the idea of setting up an experiment quickly. Although automation can be used to set up a single experiment more rapidly than can be done by hand, the distinguishing feature of a high throughput technology is the sustainability of the increased rate. PMID:21571072

  20. Electrochemical Machining of Metal Plates

    SciTech Connect

    Cooper, J F; Evans, M C

    2005-03-04

    Electrochemical machining (ECM) with concentrated sodium chlorate electrolyte was used to rapidly cut a circular groove (13 cm diameter, 0.2 cm wide) through a 0.15 cm thick sheet of steel--thus opening a 5-inch porthole in as little as 10 minutes. The most favorable operating conditions were: T = 22 C; chlorate concentration 600 g NaClO{sub 3}/liter-solution; electric power of 100 A at 10 V; and flow of 0.5 l/s at a pressure drop of 10 kPa (1.5 psi). The porthole may be removed entirely by electrochemical means, or the electrochemical dissolution may continue until only thin membrane remains that is subsequently cut with a utility knife. An array of thermocouples was used to track temperature in the flowing solution and in the trough being machined; the maximum increase in temperature in the trough was 5 C over that of the flowing electrolyte which increased in temperature by 19 C because of power dissipation. ECM is shown feasible for rapid perforation of plates of ferrous and non-ferrous metals using portable equipment and commercial batteries. The technique can be extended to cut perforations of arbitrary shape through non-planar surfaces using a deformable ring cathode. Analysis of the power requirements for electrolyte flow and ECM indicate a total system weight of less than 45 kg (100 lb) using a commercial NiMH battery. The technique is recommended for reduction to practice and demonstration on full scale as an engineering prototype.

  1. Modeling Residual Stresses in Ceramic Plates

    SciTech Connect

    Cantavella, V.; Moreno, A.; Mezquita, A.; Reig, Y.

    2008-02-15

    The generation of residual stresses during cooling of layered ceramic plates has been modeled. Each plate comprises a body and two thin layers (engobe and glaze). The model takes into account two types of stresses: thermal stresses, resulting from temperature gradients inside the plate during cooling, and the stresses produced by the mismatch of the coefficient of thermal expansion (CTE) of the layers. The body has been simulated using a linear viscoelastic constitutive equation. The engobe and the glaze layer have been considered as elastic solids below a certain temperature (setting temperature: T{sub a}). Above T{sub a} these two layers have no mechanical influence on the body.

  2. Bi-coolant flat plate solar collector

    NASA Astrophysics Data System (ADS)

    Chon, W. Y.; Green, L. L.

    The feasibility study of a flat plate solar collector which heats air and water concurrently or separately was carried out. Air flows above the collector absorber plate, while water flows in tubes soldered or brazed beneath the plate. The collector efficiencies computed for the flow of both air and water are compared with those for the flow of a single coolant. The results show that the bi-coolant collector efficiency computed for the entire year in Buffalo, New York is higher than the single-coolant collector efficiency, although the efficiency of the water collector is higher during the warmer months.

  3. Ion plating with an induction heating source

    NASA Technical Reports Server (NTRS)

    Spalvins, T.; Brainard, W. A.

    1976-01-01

    Induction heating is introduced as an evaporation heat source in ion plating. A bare induction coil without shielding can be directly used in the glow discharge region with no arcing. The only requirement is to utilize an rf inductive generator with low operating frequency of 75 kHz. Mechanical simplicity of the ion plating apparatus and ease of operation is a great asset for industrial applications; practically any metal such as nickel, iron, and the high temperature refractories can be evaporated and ion plated.

  4. Seismic anisotropy above a subducting plate

    SciTech Connect

    Shih, X.R.; Meyer, R.P. ); Schneider, J.F. )

    1991-08-01

    Shear-wave splitting observed in northeastern Colombia has provided evidence of seismic anisotropy in a shear zone immediately above a subducting plate. In an upper mantle composed mainly of olivine (57%) and orthopyroxene (17%), the splitting can be interpreted by wave propagation in an anisotropic medium of orthorhombic symmetry that results from alignment of these intrinsically anisotropic minerals. The mechanism of alignment is most likely the shearing associated with the subduction, aided by fluids migrating from the subducting plate when the plate exceeds 100 km in depth.

  5. Strongly coupled stress waves in heterogeneous plates.

    NASA Technical Reports Server (NTRS)

    Wang, A. S. D.; Chou, P. C.; Rose, J. L.

    1972-01-01

    Consideration of coupled stress waves generated by an impulsive load applied at one end of a semiinfinite plate. For the field equations governing the one-dimensional coupled waves a hyperbolic system of equations is obtained in which a strong coupling in the second derivatives exists. The method of characteristics described by Chou and Mortimer (1967) is extended to cover the case of strong coupling, and a study is made of the transient stress waves in a semiinfinite plate subjected to an initial step input. Coupled discontinuity fronts are found to propagate at different velocities. The normal plate stress and the bending moment at different time regimes are illustrated by graphs.

  6. Rough Fresnel zone plates over metallic surfaces.

    PubMed

    Salgado-Remacha, Francisco Javier; Sanchez-Brea, Luis Miguel; Alvarez-Rios, Francisco Javier; Bernabeu, Eusebio

    2010-04-01

    We analyze the focusing properties of Fresnel zone plates fabricated over steel tapes using laser ablation. Our intention is to implement the use of micro-optical elements when the use of conventional chrome-glass elements is not indicated. Because of the manufacture process, the surface presents a certain anisotropic roughness, which reduces the focusing properties. First, we develop numerical simulations by means of the Rayleigh-Sommerfeld approach, showing how roughness in both levels of the Fresnel zone plate affects the focalization of the lens. We also manufacture Fresnel zone plates over steel tape, and perform experimental verification that corroborates the numerical results. PMID:20357856

  7. Improvements in Cold-Plate Fabrication

    NASA Technical Reports Server (NTRS)

    Zaffetti, Mark A.; Taddey, Edmund P.; Laurin, Michael B.; Chabebe, Natalia

    2012-01-01

    Five improvements are reported in cold-plate fabrication. This cold plate is part of a thermal control system designed to serve on space missions. The first improvement is the merging of the end sheets of the cold plate with the face sheets of the structural honeycomb panel. The cold plate, which can be a brazed assembly, uses the honeycomb face sheet as its end sheet. Thus, when the honeycomb panel is fabricated, the face sheet that is used is already part of the cold plate. In addition to reducing weight, costs, and steps, the main benefit of this invention is that it creates a more structurally sound assembly. The second improvement involves incorporation of the header into the closure bar to pass the fluid to a lower layer. Conventional designs have used a separate header, which increases the geometry of the system. The improvement reduces the geometry, thus allowing the cold plate to fit into smaller area. The third improvement eliminates the need of hose, tube, or manifold to supply the cooling fluid externally. The external arrangement can be easily damaged and is vulnerable to leakage. The new arrangement incorporates an internal fluid transfer tube. This allows the fluid to pass from one cold plate to the other without any exposed external features. The fourth improvement eliminates separate fabrication of cold plate(s) and structural members followed by a process of attaching them to each other. Here, the structural member is made of material that can be brazed just as that of the cold plate. Now the structural member and the cold plate can be brazed at the same time, creating a monolithic unit, and thus a more structurally sound assembly. Finally, the fifth improvement is the elimination of an additional welding step that can damage the braze joints. A tube section, which is usually welded on after the braze process, is replaced with a more structurally sound configuration that can be brazed at the same time as the rest of the cold plate.

  8. Laminated anisotropic reinforced plastic plates and shells

    NASA Technical Reports Server (NTRS)

    Korolev, V. I.

    1981-01-01

    Basic technical theories and engineering calculation equations for anisotropic plates and shells made of rigid reinforced plastics, mainly laminated fiberglass, are presented and discussed. Solutions are given for many problems of design of structural plates and shells, including curved sections and tanks, as well as two chapters on selection of the optimum materials, are given. Accounting for interlayer shearing and transverse separation, which are new engineering properties, are discussed. Application of the results obtained to thin three ply plates and shells wth a light elastic filler is presented and discussed.

  9. Screen test for cadmium and nickel plates

    NASA Technical Reports Server (NTRS)

    Phan, Angie H.; Zimmerman, Albert H.

    1994-01-01

    A new procedure is described which was recently developed to quantify loading uniformity of nickel and cadmium plates and to screen finished electrodes prior to cell assembly. The technique utilizes the initial solubility rates of the active material in a standard chemical deloading solution at fixed conditions. The method can provide a reproducible indication of plate loading uniformity in situations where high surface loading limits the free flow of deloading solution into the internal porosity of the sinter plate. A preliminary study indicates that 'good' cell performance is associated with higher deloading rates.

  10. Fiber optic mounted laser driven flyer plates

    SciTech Connect

    Paisley, D.L.

    1990-12-31

    This invention is comprised of a laser driven flyer plate where the flyer plate is deposited directly onto the squared end of an optical fiber. The plasma generated by a laser pulse drives the flyer plate toward a target. In another embodiment, a first metal layer is deposited onto the squared end of an optical fiber, followed by a layer of a dielectric material and a second metal layer. The laser pulse generates a plasma in the first metal layer, but the plasma is kept away from the second metal layer by the dielectric layer until the pressure reaches the point where shearing occurs. 2 figs.

  11. Modeling Residual Stresses in Ceramic Plates

    NASA Astrophysics Data System (ADS)

    Cantavella, V.; Moreno, A.; Mezquita, A.; Reig, Y.

    2008-02-01

    The generation of residual stresses during cooling of layered ceramic plates has been modeled. Each plate comprises a body and two thin layers (engobe and glaze). The model takes into account two types of stresses: thermal stresses, resulting from temperature gradients inside the plate during cooling, and the stresses produced by the mismatch of the coefficient of thermal expansion (CTE) of the layers. The body has been simulated using a linear viscoelastic constitutive equation. The engobe and the glaze layer have been considered as elastic solids below a certain temperature (setting temperature: Ta). Above Ta these two layers have no mechanical influence on the body.

  12. Effusion plate using additive manufacturing methods

    DOEpatents

    Johnson, Thomas Edward; Keener, Christopher Paul; Ostebee, Heath Michael; Wegerif, Daniel Gerritt

    2016-04-12

    Additive manufacturing techniques may be utilized to construct effusion plates. Such additive manufacturing techniques may include defining a configuration for an effusion plate having one or more internal cooling channels. The manufacturing techniques may further include depositing a powder into a chamber, applying an energy source to the deposited powder, and consolidating the powder into a cross-sectional shape corresponding to the defined configuration. Such methods may be implemented to construct an effusion plate having one or more channels with a curved cross-sectional geometry.

  13. Viscoelastic flow between two infinite parallel porous plates, one plate oscillating and the other plate in uniform motion

    NASA Astrophysics Data System (ADS)

    Roy, J. S.; Nayak, P.

    1981-09-01

    An iteration procedure is used to solve fluid dynamics equations describing viscoelastic incompressible flow between two infinite parallel porous plates, one oscillating and the other in uniform motion. The solutions obtained are valid for small values of the elastic parameter S. The effects of the Reynolds number and the elastic parameter S on the velocity distribution and the shearing stress at the plates are analyzed.

  14. Electromagnetic semitransparent δ-function plate: Casimir interaction energy between parallel infinitesimally thin plates

    NASA Astrophysics Data System (ADS)

    Parashar, Prachi; Milton, Kimball A.; Shajesh, K. V.; Schaden, M.

    2012-10-01

    We derive boundary conditions for electromagnetic fields on a δ-function plate. The optical properties of such a plate are shown to necessarily be anisotropic in that they only depend on the transverse properties of the plate. We unambiguously obtain the boundary conditions for a perfectly conducting δ-function plate in the limit of infinite dielectric response. We show that a material does not “optically vanish” in the thin-plate limit. The thin-plate limit of a plasma slab of thickness d with plasma frequency ωp2=ζp/d reduces to a δ-function plate for frequencies (ω=iζ) satisfying ζd≪ζpd≪1. We show that the Casimir interaction energy between two parallel perfectly conducting δ-function plates is the same as that for parallel perfectly conducting slabs. Similarly, we show that the interaction energy between an atom and a perfect electrically conducting δ-function plate is the usual Casimir-Polder energy, which is verified by considering the thin-plate limit of dielectric slabs. The “thick” and “thin” boundary conditions considered by Bordag are found to be identical in the sense that they lead to the same electromagnetic fields.

  15. Thermo-mechanical buckling analysis of FGM plate using generalized plate theory

    NASA Astrophysics Data System (ADS)

    Sharma, Kanishk; Kumar, Dinesh; Gite, Anil

    2016-05-01

    This paper investigates the thermo-mechanical buckling behavior of simply-supported FGM plate under the framework of generalized plate theory (GPT), which includes classical plate theory (CPT), first order shear deformation theory (FSDT) and higher order shear deformation theory (HSDT) as special cases. The governing equations for FGM plate under thermal and mechanical loading conditions are derived from the principle of virtual displacements and Navier-type solution is assumed for simply supported boundary condition. The efficiency and applicability of presented methodology is illustrated by considering various examples of thermal and mechanical buckling of FGM plates. The closed form solutions in the form of critical thermal and mechanical buckling loads, predicted by CPT, FSDT and HSDT are compared for different side-to-thickness of FGM plate. Subsequently, the effect of material gradation profile on critical buckling parameters is examined by evaluating the buckling response for a range of power law indexes. The effect of geometrical parameters on mechanical buckling of FGM plate under uni-axial and bi-axial loading conditions are also illustrated by calculating the critical load for various values of slenderness ratios. Furthermore a comparative analysis of critical thermal buckling loads of FGM plate for different temperature profiles is also presented. It is identified that all plate theories predicted approximately same critical buckling loads and critical buckling temperatures for thin FGM plate, however for thick FGM plates, CPT overestimates the critical buckling parameters. Moreover the critical buckling loads and critical buckling temperatures of FGM plate are found to be significantly lower than the corresponding homogenous isotropic ceramic plate (n=0).

  16. Coloured Rings Produced on Transparent Plates

    ERIC Educational Resources Information Center

    Suhr, Wilfried; Schlichting, H. Joachim

    2007-01-01

    Beautiful colored interference rings can be produced by using transparent plates such as window glass. A simple model explains this effect, which was described by Newton but has almost been forgotten. (Contains 11 figures.)

  17. The Elasto-Plastic Stability of Plates

    NASA Technical Reports Server (NTRS)

    Ilyushin, A. A.

    1947-01-01

    This article explains results developed from the following research: 'The Stability of Plates and Shells beyond the Elastic Limit.' A significant improvement is found in the derivation of the relations between the stress factors and the strains resulting from the instability of plates and shells. In a strict analysis, the problem reduces to the solution of two simultaneous nonlinear partial differential equations of the fourth order in the deflection and stress function, and in the approximate analysis to a single linear equation of the Bryan type. Solutions are given for the special cases of a rectangular plate buckling into a cylindrical form, and of an arbitrarily shaped plate under uniform compression. These solutions indicate that the accuracy obtained by the approximate method is satisfactory.

  18. A New Spin: CDs as Printing Plates.

    ERIC Educational Resources Information Center

    Gamble, Harriet

    2000-01-01

    Describes a printmaking activity for use in tenth- to twelfth-grade art classes. Students use compact discs as printing plates, on which they depict a musical theme with drypoint etching. Discusses the process in detail. (CMK)

  19. Characterization of Tri-lab Tantalum Plate.

    SciTech Connect

    Buchheit, Thomas E.; Cerreta, Ellen K.; Deibler, Lisa Anne; Chen, Shu-Rong; Michael, Joseph R.

    2014-09-01

    This report provides a detailed characterization Tri-lab Tantalum (Ta) plate jointly purchased from HCStark Inc. by Sandia, Los Alamos and Lawrence Livermore National Laboratories. Data in this report was compiled from series of material and properties characterization experiments carried out at Sandia (SNL) and Los Alamos (LANL) Laboratories through a leveraged effort funded by the C2 campaign. Results include microstructure characterization detailing the crystallographic texture of the material and an increase in grain size near the end of the rolled plate. Mechanical properties evaluations include, compression cylinder, sub-scale tension specimen, micohardness and instrumented indentation testing. The plate was found to have vastly superior uniformity when compare with previously characterized wrought Ta material. Small but measurable variations in microstructure and properties were noted at the end, and at the top and bottom edges of the plate.

  20. Polar Plate Theory for Orthogonal Anisotropy

    NASA Technical Reports Server (NTRS)

    Bailey, Michelle D.; Bower, Mark V.

    2000-01-01

    Laminated fiber-reinforced (or filamentary) composites are used today for their high strength-to-weight and stiffness-to-weight ratios. However, because of the anisotropic behavior of composites, determining the response on a macroscopic scale is challenging. This is particularly evident in the evaluation of the governing differential equations of a circular disk with the fibers of the lamina oriented with rectilinear orthogonality. This includes any situation involving a composite plate of circular geometry in which out-of-plane displacements due to load are desired, such as fastener pull through loading of a composite plate. Current analysis techniques use numerical methods with rectilinear coordinate systems to solve problems with circular geometry. These analyses over predict plate stiffness by 20% and underpredict failure by 70%. Consequently, there is a need to transform classical composite plate theory to a polar coordinate system. In order to better analyze structures with circular geometries the classical composite plate equations are transformed into the plate equations for a rectilinearly anisotropic composite in polar coordinates. A composite plate is typically a laminate of fibers in rectilinear directions. Subsequent to the lay-tip the necessary geometry is cut out of a rectangular plate. In a similar manner, the derivation of the plate equation starts with the fundamental definitions of strain, displacement and curvature and incorporates the material property angular dependence into the equilibrium equations for a differential polar element. In the transformed state, the stiffness coefficients are no longer constant, adding to the complexity of the governing differential equations. This paper discusses the new derivation and evaluation of the plate equations for a circular composite disk with orthogonal rectilinear anisotropy. The resultant new three partial differential equations, which describe the circular anisotropic plate, can be used to

  1. Vibro-acoustic analysis of composite plates

    NASA Astrophysics Data System (ADS)

    Sarigül, A. S.; Karagözlü, E.

    2014-03-01

    Vibro-acoustic analysis plays a vital role on the design of aircrafts, spacecrafts, land vehicles and ships produced from thin plates backed by closed cavities, with regard to human health and living comfort. For this type of structures, it is required a coupled solution that takes into account structural-acoustic interaction which is crucial for sensitive solutions. In this study, coupled vibro-acoustic analyses of plates produced from composite materials have been performed by using finite element analysis software. The study has been carried out for E-glass/Epoxy, Kevlar/Epoxy and Carbon/Epoxy plates with different ply angles and numbers of ply. The effects of composite material, ply orientation and number of layer on coupled vibro-acoustic characteristics of plates have been analysed for various combinations. The analysis results have been statistically examined and assessed.

  2. The Continental Plates are Getting Thicker.

    ERIC Educational Resources Information Center

    Kerr, Richard A.

    1986-01-01

    Reviews seismological studies that provide evidence of the existence of continental roots beneath the continents. Suggests, that through the collisions of plate tectonics, continents stabilized part of the mobile mantle rock beneath them to form deep roots. (ML)

  3. Ultralight shape-recovering plate mechanical metamaterials

    NASA Astrophysics Data System (ADS)

    Davami, Keivan; Zhao, Lin; Lu, Eric; Cortes, John; Lin, Chen; Lilley, Drew E.; Purohit, Prashant K.; Bargatin, Igor

    2015-12-01

    Unusual mechanical properties of mechanical metamaterials are determined by their carefully designed and tightly controlled geometry at the macro- or nanoscale. We introduce a class of nanoscale mechanical metamaterials created by forming continuous corrugated plates out of ultrathin films. Using a periodic three-dimensional architecture characteristic of mechanical metamaterials, we fabricate free-standing plates up to 2 cm in size out of aluminium oxide films as thin as 25 nm. The plates are formed by atomic layer deposition of ultrathin alumina films on a lithographically patterned silicon wafer, followed by complete removal of the silicon substrate. Unlike unpatterned ultrathin films, which tend to warp or even roll up because of residual stress gradients, our plate metamaterials can be engineered to be extremely flat. They weigh as little as 0.1 g cm-2 and have the ability to `pop-back' to their original shape without damage even after undergoing multiple sharp bends of more than 90°.

  4. Plate measurements and reductions at Muenster

    NASA Astrophysics Data System (ADS)

    Teuber, D.; Tucholke, H. J.; Volkmer, C. C.; Budell, R.; Duemmler, R.; Horstmann, H.; Scheuer, H. G.; Seitter, W. C.

    1984-04-01

    A microdensitometer used with astronomical photography plates is described. Positional error derived from repeated measurements of a sharp edge is of the order of 0.1 microns with only small increases for scan speeds near the beginning and the end of the full scale from 0 to 226 mm/sec. Positional measurements of stars using Gauss fits to marginal distributions yield differences of 0.6 microns for different plate orientations. Differences with respect to catalog positions, using quadratic reduction models, yield a mean of 1.2 microns for well-exposed IIa-O plates with plate scales of 40 sec/mm and reference stars from the AGK3 corresponding to 0.05 sec for single measurements. Photometric accuracy for a typical multiplier voltage is 0.25% in density 3, 0.29% in transmission 1.

  5. Stop motion microphotography of laser driven plates

    SciTech Connect

    Frank, A.M.; Trott, W.M.

    1994-09-01

    Laser driven plates have been used for several years for high velocity shock wave and impact studies. Recent questions about the integrity and ablation rates of these plates coupled with an improved capability for microscopic stop motion photography led to this study. For these experiments, the plates were aluminum, coated on the ends of optical fibers. A high power laser pulse in the fiber ionizes the aluminum at the fiber/coating interface. The plasma thus created accelerates the remaining aluminum to high velocities, several kilometers per second. We defined {open_quotes}thick{close_quotes} or {open_quotes}thin{close_quotes} coatings as those where a flying plate (flyer) was launched vs. the material being completely ionized. Here we were specifically interested in the thick/thin boundary to develop data for the numerical models attempting to predict flyer behavior.

  6. 19 CFR 115.32 - Approval plates.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... clearly visible place on or near one of the doors or other main openings of each container manufactured to...). The following shall be embossed on or stamped into the surface of the approval plate: (a)...

  7. Anterior Cervical Discectomy and Fusion with Plating

    MedlinePlus Videos and Cool Tools

    Anterior Cervical Discectomy and Fusion with Plating Broward Health Medical Center Fort Lauderdale, FL November 17, 2011 I'm Dr. Matthew Moore, head of the Spine Care Center here at North Broward Medical Center. And ...

  8. White Light Photorefractive Phase Zone Plates

    NASA Astrophysics Data System (ADS)

    Gao, Yuan-Mei; Liu, Si-Min

    2008-02-01

    Incoherent white light from an incandescent source is employed to fabricate volume phase zone plates in LiNbO3: Fe, for the first time to our knowledge, which can guide and modulate the input white light or laser light. The diffractive efficiency of the white light volume phase zone plates fabricated can reach as high as 12%. In addition, we test the volume phase zone plates by a probe beam and find that the volume phase zone plate is present in the direction perpendicular to the c-axis and absent in the direction parallel to the c-axis. This directly proves the existence of photovoltaic photorefractive anisotropy of white light.

  9. Loading errors in cone-plate rheometry

    NASA Astrophysics Data System (ADS)

    Davies, A. J.

    2015-12-01

    Errors arising from the under- and overfilling of cone-plate geometries have been investigated for combinations of smooth and micro-roughened cone-plate geometries. We observed experimentally that 0.1 ml deviations in the loading volume, such as can occur due to subjective filling or evaporation, will proportionally change the measured viscosity by 2-3%. We also give a simple method to avoid these errors during routine measurements.

  10. Electrochemical cell and separator plate thereof

    DOEpatents

    Baker, Bernard S.; Dharia, Dilip J.

    1979-10-02

    A fuel cell includes a separator plate having first and second flow channels extending there through contiguously with an electrode and respectively in flow communication with the cell electrolyte and in flow isolation with respect to such electrolyte. In fuel cell system arrangement, the diverse type channels are supplied in common with process gas for thermal control purposes. The separator plate is readily formed by corrugation of integral sheet material. 10 figs.

  11. Electrochemical cell and separator plate thereof

    DOEpatents

    Baker, Bernard S.; Dharia, Dilip J.

    1979-01-01

    A fuel cell includes a separator plate having first and second flow channels extending therethrough contiguously with an electrode and respectively in flow communication with the cell electrolyte and in flow isolation with respect to such electrolyte. In fuel cell system arrangement, the diverse type channels are suplied in common with process gas for thermal control purposes. The separator plate is readily formed by corrugation of integral sheet material.

  12. Plate Tectonics in the Late Paleozoic

    NASA Astrophysics Data System (ADS)

    Domeier, Mat; Torsvik, Trond

    2014-05-01

    As the chronicle of plate motions through time, paleogeography is fundamental to our understanding of plate tectonics and its role in shaping the geology of the present-day. To properly appreciate the history of tectonics—and its influence on the deep Earth and climate—it is imperative to seek an accurate and global model of paleogeography. However, owing to the incessant loss of oceanic lithosphere through subduction, the paleogeographic reconstruction of 'full-plates' (including oceanic lithosphere) becomes increasingly challenging with age. Prior to 150 Ma ~60% of the lithosphere is missing and reconstructions are developed without explicit regard for oceanic lithosphere or plate tectonic principles; in effect, reflecting the earlier mobilistic paradigm of continental drift. Although these 'continental' reconstructions have been immensely useful, the next-generation of mantle models requires global plate kinematic descriptions with full-plate reconstructions. Moreover, in disregarding (or only loosely applying) plate tectonic rules, continental reconstructions fail to take advantage of a wealth of additional information in the form of practical constraints. Following a series of new developments, both in geodynamic theory and analytical tools, it is now feasible to construct full-plate models that lend themselves to testing by the wider Earth-science community. Such a model is presented here for the late Paleozoic (410-250 Ma). Although we expect this model to be particularly useful for numerical mantle modeling, we hope that it can also serve as a general framework for understanding late Paleozoic tectonics, one on which future improvements can be built and further tested.

  13. Method for plating with metal oxides

    DOEpatents

    Silver, G.L.; Martin, F.S.

    1994-08-23

    A method is disclosed of plating hydrous metal oxides on at least one substrate, which method is indifferent to the electrochemical properties of the substrate, and comprises reacting metallic ions in aqueous solution with an appropriate oxidizing agent such as sodium hypochlorite or calcium sulfite with oxygen under suitable conditions of pH and concentration such that oxidation and precipitation of metal oxide are sufficiently slow to allow satisfactory plating of metal oxide on the substrate. 1 fig.

  14. Composite bipolar plate for electrochemical cells

    DOEpatents

    Wilson, Mahlon S.; Busick, Deanna N.

    2001-01-01

    A bipolar separator plate for fuel cells consists of a molded mixture of a vinyl ester resin and graphite powder. The plate serves as a current collector and may contain fluid flow fields for the distribution of reactant gases. The material is inexpensive, electrically conductive, lightweight, strong, corrosion resistant, easily mass produced, and relatively impermeable to hydrogen gas. The addition of certain fiber reinforcements and other additives can improve the properties of the composite material without significantly increasing its overall cost.

  15. Plate Tectonics, Geographical Information System, paleogeography

    SciTech Connect

    Moore, Thomas L.; Scotese, Christopher

    2002-05-24

    The PaleoX.framwork is a dynamically linked/loaded framework for Cocoa applications. The primary goal of this library is to standardize several elements used for working with paleogeographic data. This includes objects designed to organize information for tectonic plates, including maps, rotation objects, plate names, and designations. In addition, PaleoX provides object-oriented solutions for handling standard paleogeographic file formats from the PALEOMAP Project.

  16. Method for plating with metal oxides

    DOEpatents

    Silver, Gary L.; Martin, Frank S.

    1994-08-23

    A method of plating hydrous metal oxides on at least one substrate, which method is indifferent to the electrochemical properties of the substrate, and comprises reacting metallic ions in aqueous solution with an appropriate oxidizing agent such as sodium hypochlorite or calcium sulfite with oxygen under suitable conditions of pH and concentration such that oxidation and precipitation of metal oxide are sufficiently slow to allow satisfactory plating of metal oxide on the substrate.

  17. Lighting system with heat distribution face plate

    DOEpatents

    Arik, Mehmet; Weaver, Stanton Earl; Stecher, Thomas Elliot; Kuenzler, Glenn Howard; Wolfe, Jr., Charles Franklin; Li, Ri

    2013-09-10

    Lighting systems having a light source and a thermal management system are provided. The thermal management system includes synthetic jet devices, a heat sink and a heat distribution face plate. The synthetic jet devices are arranged in parallel to one and other and are configured to actively cool the lighting system. The heat distribution face plate is configured to radially transfer heat from the light source into the ambient air.

  18. Brewster-Plate Spoiler for Laser Spectrometer

    NASA Technical Reports Server (NTRS)

    Webster, C. R.

    1986-01-01

    Oscillating Brewster plate reduces effects of unwanted interference fringes on absorption-spectroscopic measurements obtained with tuned diode lasers. Plate modulates optical-path length past several resonance peaks causing interference fringes to pass by rapidly and become blurred. Thus, fringe effects averaged out over time. Technique used at other wavelengths from ultraviolet to infrared and in spectrometers with short or long optical paths, including those with retroreflectors or multipass cells.

  19. Reconstructing Plate Motions on Europa with GPlates

    NASA Astrophysics Data System (ADS)

    Cutler, B. B.; Collins, G. C.; Prockter, L. M.; Patterson, G.; Kattenhorn, S. A.; Rhoden, A.; Cooper, C. M.

    2015-12-01

    Observations of past plate tectonic - like motions in Europa's icy lithosphere have been reported in previous studies. Quantifying the nature, age, and amount of plate motion is important for geophysical models of Europa's ice shell and for astrobiology, since subsumed pates could drive the flow of nutrients into the subsurface ocean. We have used GPlates software (Williams et al., GSA Today 2012) and a mosaic of regional-resolution Galileo SSI data from orbits E11, E15, E17, and E19 to make interactive reconstructions of both the Northern Falga region (60N, 220W) and the Castalia Macula region (0N, 225W). The advantage of this method is that plate motions are calculated on a sphere, while still maintaining the original Galileo image pieces in their proper geographic locations. Previous work on the Castalia Macula region (Patterson et al. J.Struct.Geol. 2006) and the adjacent Phaidra Linea region (Patterson and Ernst, LPSC 2011) found offsets along spreading boundaries, and then calculated the best fit finite rotations to close those offsets. Though this method is mathematically rigorous and gives a statistical goodness of fit, it is not easy to test multiple hypotheses for candidate piercing points or divisions of candidate plate boundaries. Through the interactive environment, we found that we could better account for observed offsets in this region by breaking it into 32 different plates. Patterson and Ernst broke the Phaidra region into 6 plates which exhibited nonrigid behavior, where our study breaks it into 16 rigid plates. The Northern Falga Regio area is interesting due to the potential for large amounts of subsumption of Europa's icy crust in this location. The previous reconstruction (Kattenhorn and Prockter, Nat.Geosci. 2014) was based on planar geometry, and we have replicated these results using a spherically-based reconstruction. We will present the plate maps and reconstructions for both of these regions, along with the best fit rotation poles.

  20. Tomography, the geoid and plate motions

    NASA Technical Reports Server (NTRS)

    Gable, Carl W.; O'Connell, Richard J.

    1991-01-01

    The dynamics of the earth's mantle and its relationship to mantle structure as revealed by seismic tomography, the geoid, and plate motions are discussed in a critical review of U.S. research from the period 1987-1990. Sections are devoted to plates and mantle convection; seismic anomalies, flow, and the geoid; subducted slabs and the 670-km discontinuity; the physical properties of the mantle; plumes; and computational and experimental modeling efforts. Also included is a comprehensive bibliography for the period.

  1. A clamped rectangular plate containing a crack

    NASA Technical Reports Server (NTRS)

    Tang, R.; Erdogan, F.

    1985-01-01

    The general problem of a rectangular plate clamped along two parallel sides and containing a crack parallel to the clamps is considered. The problem is formulated in terms of a system of singular integral equations and the asymptotic behavior of the stress state near the corners is investigated. Numerical examples are considered for a clamped plate without a crack and with a centrally located crack, and the stress intensity factors and the stresses along the clamps are calculated.

  2. Plated-through hole testing. Final repot

    SciTech Connect

    Abel, W.B.

    1980-05-01

    An improved microresistance testing method to measure the thickness of copper plating in plated-through holes of double-sided printed wiring boards is presented. A new probe design, combined with a microprocessor controller, makes it possible for a direct reading tester to provide variables data. Tester design and software programs for the system are included. Results of correlation studies, comparing the improved resistance method to cross-sectional measurements are presented. Limitations on the microresistance test method are discussed.

  3. Improved Orifice Plate for Spray Gun

    NASA Technical Reports Server (NTRS)

    Cunningham, W.

    1986-01-01

    Erratic spray pattern of commercial spray gun changed to repeatable one by simple redesign of two parts. In modified spray gun orifice plate and polytetrafluoroethylene bushing redesigned to assure centering and alignment with nozzle. Such improvement useful in many industrial applications requiring repeatable spray patterns. Might include spraying of foam insulation, paint, other protective coatings, detergents, abrasives, adhesives, process chemicals, or fuels. Unmodified spray gun produces erratic spray because lateral misalignment between orifice plate and nozzle.

  4. [Experimental study on carbon fiber reinforced plastic plate--analysis of stabilizing force required for plate].

    PubMed

    Iizuka, H

    1990-11-01

    Plates currently in use for the management of bone fracture made of metal present with various problems. We manufactured carbon fiber reinforced plastic (CFRP) plates from Pyrofil T/530 puriplegs overlaid at cross angles of +/- 10 degrees, +/- 20 degrees, and +/- 30 degrees for trial and carried out an experimental study on rabbit tibiofibular bones using 316L stainless steel plates of comparable shape and size as controls. The results indicate the influence of CFRP plate upon cortical bone was milder than that of stainless steel plate, with an adequate stabilizing force for the repair of fractured rabbit tibiofibular bones. CFRP has the advantages over metals of being virtually free from corrosion and fatigue, reasonably radiolucent and able to meet a wide range of mechanical requirements. This would make CFRP plate quite promising as a new devices of treating fracture of bones. PMID:2273322

  5. Image simulation for automatic license plate recognition

    NASA Astrophysics Data System (ADS)

    Bala, Raja; Zhao, Yonghui; Burry, Aaron; Kozitsky, Vladimir; Fillion, Claude; Saunders, Craig; Rodríguez-Serrano, José

    2012-01-01

    Automatic license plate recognition (ALPR) is an important capability for traffic surveillance applications, including toll monitoring and detection of different types of traffic violations. ALPR is a multi-stage process comprising plate localization, character segmentation, optical character recognition (OCR), and identification of originating jurisdiction (i.e. state or province). Training of an ALPR system for a new jurisdiction typically involves gathering vast amounts of license plate images and associated ground truth data, followed by iterative tuning and optimization of the ALPR algorithms. The substantial time and effort required to train and optimize the ALPR system can result in excessive operational cost and overhead. In this paper we propose a framework to create an artificial set of license plate images for accelerated training and optimization of ALPR algorithms. The framework comprises two steps: the synthesis of license plate images according to the design and layout for a jurisdiction of interest; and the modeling of imaging transformations and distortions typically encountered in the image capture process. Distortion parameters are estimated by measurements of real plate images. The simulation methodology is successfully demonstrated for training of OCR.

  6. Abrupt plate accelerations shape rifted continental margins.

    PubMed

    Brune, Sascha; Williams, Simon E; Butterworth, Nathaniel P; Müller, R Dietmar

    2016-08-11

    Rifted margins are formed by persistent stretching of continental lithosphere until breakup is achieved. It is well known that strain-rate-dependent processes control rift evolution, yet quantified extension histories of Earth's major passive margins have become available only recently. Here we investigate rift kinematics globally by applying a new geotectonic analysis technique to revised global plate reconstructions. We find that rifted margins feature an initial, slow rift phase (less than ten millimetres per year, full rate) and that an abrupt increase of plate divergence introduces a fast rift phase. Plate acceleration takes place before continental rupture and considerable margin area is created during each phase. We reproduce the rapid transition from slow to fast extension using analytical and numerical modelling with constant force boundary conditions. The extension models suggest that the two-phase velocity behaviour is caused by a rift-intrinsic strength--velocity feedback, which can be robustly inferred for diverse lithosphere configurations and rheologies. Our results explain differences between proximal and distal margin areas and demonstrate that abrupt plate acceleration during continental rifting is controlled by the nonlinear decay of the resistive rift strength force. This mechanism provides an explanation for several previously unexplained rapid absolute plate motion changes, offering new insights into the balance of plate driving forces through time. PMID:27437571

  7. Vibration analysis of annular-like plates

    NASA Astrophysics Data System (ADS)

    Cheng, L.; Li, Y. Y.; Yam, L. H.

    2003-05-01

    The existence of eccentricity of the central hole for an annular plate results in a significant change in the natural frequencies and mode shapes of the structure. In this paper, the vibration analysis of annular-like plates is presented based on numerical and experimental approaches. Using the finite element analysis code Nastran, the effects of the eccentricity, hole size and boundary condition on vibration modes are investigated systematically through both global and local analyses. The results show that analyses for perfect symmetric conditions can still roughly predict the mode shapes of "recessive" modes of the plate with a slightly eccentric hole. They will, however, lead to erroneous results for "dominant" modes. In addition, the residual displacement mode shape is verified as an effective parameter for identifying damage occurring in plate-like structures. Experimental modal analysis on a clamped-free annular-like plate is performed, and the results obtained reveal good agreement with those obtained by numerical analysis. This study provides guidance on modal analysis, vibration measurement and damage detection of plate-like structures.

  8. The planar jet-plate oscillator

    NASA Astrophysics Data System (ADS)

    Arthurs, David; Ziada, Samir

    2011-01-01

    The aeroacoustic noise generated by a high speed, planar gas jet impinging on a flat plate is investigated experimentally. The jet used in this study is typical of those commonly found in industrial applications such as in various coating control and heat transfer processes. Normal jet impingement on the plate is found to generate strong acoustic tones over a wide range of impingement distances and jet velocities. The characteristics of these tones, as a function of the jet velocity and impingement distance, are quantified. Phase and amplitude measurements of the pressure fluctuations on the impingement plate indicate that the acoustic tones are generated by an antisymmetric instability mode of the jet oscillation. The effect of plate inclination in both the transverse and span-wise directions, with respect to the incident jet, is also studied. The jet-plate tone is found to be much more sensitive to changes in the span-wise plate inclination than to changes in the transverse inclination, but in both cases, a complete suppression of the tone is found to be possible.

  9. Quantitative assessment of growth plate activity

    SciTech Connect

    Harcke, H.T.; Macy, N.J.; Mandell, G.A.; MacEwen, G.D.

    1984-01-01

    In the immature skeleton the physis or growth plate is the area of bone least able to withstand external forces and is therefore prone to trauma. Such trauma often leads to premature closure of the plate and results in limb shortening and/or angular deformity (varus or valgus). Active localization of bone seeking tracers in the physis makes bone scintigraphy an excellent method for assessing growth plate physiology. To be most effective, however, physeal activity should be quantified so that serial evaluations are accurate and comparable. The authors have developed a quantitative method for assessing physeal activity and have applied it ot the hip and knee. Using computer acquired pinhole images of the abnormal and contralateral normal joints, ten regions of interest are placed at key locations around each joint and comparative ratios are generated to form a growth plate profile. The ratios compare segmental physeal activity to total growth plate activity on both ipsilateral and contralateral sides and to adjacent bone. In 25 patients, ages 2 to 15 years, with angular deformities of the legs secondary to trauma, Blount's disease, and Perthes disease, this technique is able to differentiate abnormal segmental physeal activity. This is important since plate closure does not usually occur uniformly across the physis. The technique may permit the use of scintigraphy in the prediction of early closure through the quantitative analysis of serial studies.

  10. Utilization of urethral plate in hypospadias surgery

    PubMed Central

    Snodgrass, Warren T.

    2008-01-01

    Purpose Recognition the urethral plate comprises tissues that normally should have created the urethra was an important milestone in hypospadias surgery, giving rise to new operative repairs - most notably the tubularized incised plate technique. This article reviews the current state of the art for hypospadias repair using tubularized, incised plate (TIP). Materials and Methods Personal experience and literature reports were reviewed to summarize use of TIP urethroplasty for distal, proximal, and re-operative hypospadias repairs. Results The TIP can be used to correct all distal and most proximal hypospadias. The major contraindication is ventral curvature that leads to urethral plate transection for straightening, which is only necessary in some proximal cases. Reoperations can also be performed using TIP provided the urethral plate has been maintained and is not grossly scarred. Complication rates are comparable to previously used techniques, while cosmetic appearance after TIP is considered superior to other available procedures. Conclusions Recognition of the urethral plate and its incorporation into the neourethra has revolutionized hypospadias repair. The most commonly used operative procedure today is TIP. PMID:19468397

  11. Data analysis for surface plate calibration

    SciTech Connect

    Burton, R.N.

    1997-08-01

    A surface plate is used to establish a reference plane used for making precision dimensional measurements. Ideally, the surface should be perfectly flat. Since it is impossible to create a perfectly flat surface, surface plate are calibrated to determine how much they deviate from a perfectly flat surface. Once a surface plate is calibrated, the user can determine if the plate is flat enough for use in a particular application. The currently accepted method of data analysis for surface plate calibration, the Moody method, does not give optimum results because of the arbitrary way in which the reference plane is chosen. The exact solution, wherein the reference plane is located in the optimum position, has been worked out and is given in a step by step procedure along with all of the necessary equations. The amount of calculation involved in a typical example proved to be prohibitive even for a computer, so an alternate solution using a least squares criterion for locating the reference plane was developed. Results were comparable with those from Moody`s method with values being smaller or greater depending on the shape of the plate.

  12. Corrosion test cell for bipolar plates

    DOEpatents

    Weisbrod, Kirk R.

    2002-01-01

    A corrosion test cell for evaluating corrosion resistance in fuel cell bipolar plates is described. The cell has a transparent or translucent cell body having a pair of identical cell body members that seal against opposite sides of a bipolar plate. The cell includes an anode chamber and an cathode chamber, each on opposite sides of the plate. Each chamber contains a pair of mesh platinum current collectors and a catalyst layer pressed between current collectors and the plate. Each chamber is filled with an electrolyte solution that is replenished with fluid from a much larger electrolyte reservoir. The cell includes gas inlets to each chamber for hydrogen gas and air. As the gases flow into a chamber, they pass along the platinum mesh, through the catalyst layer, and to the bipolar plate. The gas exits the chamber through passageways that provide fluid communication between the anode and cathode chambers and the reservoir, and exits the test cell through an exit port in the reservoir. The flow of gas into the cell produces a constant flow of fresh electrolyte into each chamber. Openings in each cell body is member allow electrodes to enter the cell body and contact the electrolyte in the reservoir therein. During operation, while hydrogen gas is passed into one chamber and air into the other chamber, the cell resistance is measured, which is used to evaluate the corrosion properties of the bipolar plate.

  13. Variational modeling of ionic polymer plate structures

    NASA Astrophysics Data System (ADS)

    Buechler, Miles A.; Leo, Donald J.

    2006-03-01

    Ionomeric polymers are a promising class of intelligent material which exhibit electromechanical coupling similar to that of piezoelectric bimorphs. Ionomeric polymers are much more compliant than piezoelectric ceramics or polymers and have been shown to produce actuation strain on the order of 5% at operating voltages between 1 V and 5 V. This performance indicates the potential for self-actuating devices manufactured from ionomeric polymers, such as deformable mirrors or low pressure pump diaphragms. This paper presents a variational approach to the dynamic modeling of ionic polymer plates in rectangular coordinates. A linear matrix equation, which relates displacement and charge to applied forces and voltage, is developed to determine the response of the structure to applied forces and applied potentials. The modeling method is based on the incorporation of empirically determined material properties, which have been shown to be highly frequency dependent. The matrices are calculated at discrete frequencies and solved frequency-by-frequency to determine the response of the ionomeric plate structures. A model of a thin rectangular plate is developed and validated experimentally. Simulated frequency response functions are compared to experimental results for several locations on the plate. The response of the plate at certain frequencies is computed and compared to experimentally-determined response shapes. The results demonstrate the validity of the modeling approach in predicting the dynamic response of the ionomeric plate structure. These spatial solutions are also compared to experimentally determined response shapes.

  14. Thermal stresses and deflections of cross-ply laminated plates using refined plate theories

    SciTech Connect

    Khdeir, A.A.; Reddy, J.N. Virginia Polytechnic Institute and State University, Blacksburg )

    1991-12-01

    Exact analytical solutions of refined plate theories are developed to study the thermal stresses and deflections of cross-ply rectangular plates. The state-space approach in conjunction with the Levy method is used to solve exactly the governing equations of the theories under various boundary conditions. Numerical results of the higher-order theory of Reddy for thermal stresses and deflections are compared with those obtained using the classical and first-order plate theories. 14 refs.

  15. Current plate velocities relative to the hotspots incorporating the NUVEL-1 global plate motion model

    SciTech Connect

    Gripp, A.E.; Gordon, R.G. )

    1990-07-01

    NUVEL-1 is a new global model of current relative plate velocities which differ significantly from those of prior models. Here the authors incorporate NUVEL-1 into HS2-NUVEL1, a new global model of plate velocities relative to the hotspots. HS2-NUVEL1 was determined from the hotspot data and errors used by Minster and Jordan (1978) to determine AM1-2, which is their model of plate velocities relative to the hotspots. AM1-2 is consistent with Minster and Jordan's relative plate velocity model RM2. Here the authors compare HS2-NUVEL1 with AM1-2 and examine how their differences relate to differences between NUVEL-1 and RM2. HS2-NUVEL1 plate velocities relative to the hotspots are mainly similar to those of AM1-2. Minor differences between the two models include the following: (1) in HS2-NUVEL1 the speed of the partly continental, apparently non-subducting Indian plate is greater than that of the purely oceanic, subducting Nazca plate; (2) in places the direction of motion of the African, Antarctic, Arabian, Australian, Caribbean, Cocos, Eurasian, North American, and South American plates differs between models by more than 10{degree}; (3) in places the speed of the Australian, Caribbean, Cocos, Indian, and Nazca plates differs between models by more than 8 mm/yr. Although 27 of the 30 RM2 Euler vectors differ with 95% confidence from those of NUVEL-1, only the AM1-2 Arabia-hotspot and India-hotspot Euler vectors differ with 95% confidence from those of HS2-NUVEL1. Thus, substituting NUVEL-1 for RM2 in the inversion for plate velocities relative to the hotspots changes few Euler vectors significantly, presumably because the uncertainty in the velocity of a plate relative to the hotspots is much greater than the uncertainty in its velocity relative to other plates.

  16. The Philippine Sea Plate: Magnetism and reconstructions

    NASA Astrophysics Data System (ADS)

    Hall, Robert; Fuller, Michael; Ali, Jason R.; Anderson, Charles D.

    Paleomagnetic results from ocean drilling and from land on the Philippine Sea Plate indicate progressive northward translation of the entire plate during the Tertiary, although different sites suggest different ages of equatorial crossing. The difficulty of orienting ocean drilling cores has recently been remedied and Ocean Drilling Program leg 126 provided the first Philippine Sea Plate declination data from sea bottom sites. These showed large clockwise declination shifts of up to -90° since the early Oligocene. Similar large declination shifts have been reported from land sites at the eastern margin of the plate; these record similar changes in inclinations with age as ocean drilling sites. The cause of the declination deflections is controversial and they have been explained as the result of entire plate rotation, marginal basin opening, and/or local tectonic deformation at the plate edge. Because most declination data have been obtained from the eastern margin of the plate, it has proved impossible to distinguish between these three possible causes. However, new paleomagnetic data from land sites in the southern part of the Philippine Sea Plate in eastern Indonesia define two sub-areas: a region within the Sorong fault system that records variable rotations attributed to deformation at the plate edge, and a region north of the Sorong fault that records a large Tertiary, but discontinuous, clockwise rotation. Both areas record northward paleolatitude shifts with decreasing age since the beginning of the Neogene but inclinations of lower Eocene sites suggest southward movement during the Paleogene. We consider the area north of the Sorong fault to form one of the oldest parts of the plate and assume that the declination shifts record the Tertiary rotation of the western part of the plate. Using this assumption it is possible to calculate rotation poles and reconstruct the Philippine Sea Plate after calculating the rotational effects of opening the marginal

  17. Lateral plate number in low-plated threespine stickleback: a study of plasticity and heritability.

    PubMed

    Hansson, Truls H; Fischer, Barbara; Mazzarella, Anna B; Voje, Kjetil L; Vøllestad, Leif Asbjørn

    2016-05-01

    In the threespine stickleback Gasterosteus aculeatus model system, phenotypes are often classified into three morphs according to lateral plate number. Morph identity has been shown to be largely genetically determined, but substantial within-morph variation in plate number exists. In this study, we test whether plate number has a plastic component in response to salinity in the low-plated morph using a split-clutch experiment where families were split in two, one half raised in water at 0 and the other at 30 ppt salt. We find a small salinity-induced plastic effect on plate number in an unexpected direction, opposite to what we predicted: Fish raised in freshwater on average have slightly more plates than fish raised in saltwater. Our results confirm that heritability of plate number is high. Additionally, we find that variance in plate number at the family level can be predicted from other family level traits, which might indicate that epistatic interactions play a role in creating the observed pattern of lateral plate number variation. PMID:27096076

  18. The motion induced between radial extensional plates with one or both plates shrinking

    NASA Astrophysics Data System (ADS)

    Weidman, Patrick; Perocco, Enrico

    2015-11-01

    Flow between the radial extensional motion of parallel plates is studied when one plate stretches at rate a while the other shrinks at rate b, and also when both plates shrink. The flow is governed by the stretching ratio σ = b / | a | and the Reynolds number R = | a | h2 / ν , where h is the plate separation distance and ν is the fluid kinematic viscosity. When both plates shrink one can find solutions in the region σ < - 1 from those found in the region - 1 <= σ <= 0 . This feature is not available when one plate stretches and the other shrinks, and thus σ must be varied over the region σ <= 0 . The R = 0 solutions and their large- R asymptotic behaviors are determined. Using two numerical techniques, no bifurcated solutions were encountered. Results are presented for upper and lower wall shear stresses, radial pressure gradients, and radial velocity profiles for these axisymmetric flows. A region of zero wall shear stress exists for stretching/shrinking plates whilst the wall shear stresses for shrinking/shrinking plates are never zero. An interesting singular limit in solution behavior as R --> ∞ is found for the shrinking/shrinking plate flow.

  19. Assumed strain distributions for a finite strip plate bending element using Mindlin-Reissner plate theory

    NASA Technical Reports Server (NTRS)

    Chulya, Abhisak; Mullen, Robert L.

    1989-01-01

    A linear finite strip plate element based on Mindlin-Reissner plate theory is developed. The analysis is suitable for both thin and thick plates. In the formulation, new transverse shear strains are introduced and assumed constant in each two-node linear strip. The element stiffness matrix is explicitly formulated for efficient computation and computer implementation. Numerical results showing the efficiency and predictive capability of the element for the analysis of plates are presented for different support and loading conditions and a wide range of thicknesses. No sign of shear locking is observed with the newly developed element.

  20. The present-day number of tectonic plates

    NASA Astrophysics Data System (ADS)

    Harrison, Christopher G. A.

    2016-03-01

    The number of tectonic plates on Earth described in the literature has expanded greatly since the start of the plate tectonic era, when only about a dozen plates were considered in global models of present-day plate motions. With new techniques of more accurate earthquake epicenter locations, modern ways of measuring ocean bathymetry using swath mapping, and the use of space based geodetic techniques, there has been a huge growth in the number of plates thought to exist. The study by Bird (2003) proposed 52 plates, many of which were delineated on the basis of earthquake locations. Because of the pattern of areas of these plates, he suggested that there should be more small plates than he could identify. In this paper, I gather together publications that have proposed a total of 107 new plates, giving 159 plates in all. The largest plate (Pacific) is about 20 % of the Earth's area or 104 Mm2, and the smallest of which (Plate number 5 from Hammond et al. 2011) is only 273 km2 in area. Sorting the plates by size allows us to investigate how size varies as a function of order. There are several changes of slope in the plots of plate number organized by size against plate size order which are discussed. The sizes of the largest seven plates is constrained by the area of the Earth. A middle set of 73 plates down to an area of 97,563 km2 (the Danakil plate at number 80, is the plate of median size) follows a fairly regular pattern of plate size as a function of plate number. For smaller plates, there is a break in the slope of the plate size/plate number plot and the next 32 plates follow a pattern of plate size proposed by the models of Koehn et al. (2008) down to an area of 11,638 km2 (West Mojave plate # 112). Smaller plates do not follow any regular pattern of area as a function of plate number, probably because we have not sampled enough of these very small plates to reveal any clear pattern.

  1. Electroless Nickel Phosphorus Plating on AZ31

    NASA Astrophysics Data System (ADS)

    Shartal, Kh. M.; Kipouros, G. J.

    2009-04-01

    One of the major drawbacks to using magnesium parts in automotive applications is poor corrosion resistance, which can be improved with a nickel-boron coating placed on a nickel-phosphorus coating, which, in turn, is placed on a phosphate-permanganate conversion-coating layer produced on the magnesium alloy AZ31. This work reports on the determination of the optimum kinetic parameters for producing a coherent nickel-phosphorus coating using an electroless-procedure phosphate-permanganate conversion-coating layer and for studying the effects of the experimental variables of the electroless plating process on the phosphorus content, surface morphology, and structure of the electroless nickel-phosphorus (EN-P) coatings produced. Measurements of the plating rate as a function of experimental variables such as the compositions of the plating bath constituents, temperature, and pH were implemented using the weight-gain method; the phosphorus content of the EN-P coatings was measured using energy-dispersive spectroscopy (EDS) analysis. The surface morphology of the coating was examined using a scanning electron microscope (SEM); X-ray diffraction (XRD) was used to characterize the structure of each coating. An empirical rate law was determined for EN-P plating on a phosphate-permanganate conversion coating. It is found that the deposition rate of the EN-P coating increases by increasing the deposition temperature, the concentration of free nickel ions, and the concentration of hypophosphite ions in the plating bath. In addition, the deposition rate decreases by increasing both the plating bath pH and the concentration of citric acid in the plating bath.

  2. Caribbean plate tectonics from seismic tomography

    NASA Astrophysics Data System (ADS)

    Ten Brink, U. S.; Villasenor, A.

    2012-12-01

    New seismic tomography in the Caribbean shows close links between the geometry and dynamics of subducting slabs and the geology of the overriding plate. Unlike most oceanic plates, the Caribbean plate lacks identifiable seafloor magnetic anomalies and fracture zones. The plate's history has therefore been inferred primarily from land geology along the plate boundary, which is complicated by large-scale shear deformation, and from finite rotations of surrounding plates.We used more than 14 million arrival times from 300,000 earthquakes to identify P-wave velocity anomalies. We relate the anomalies to the geometry and dynamics of subducting slabs and to patterns of earthquake activity, volcanism, topographic relief, and tectonic deformation. For example, we detect two separate slabs belonging to the North and South American plates, respectively, which appear to be responsible for morphologic and tectonic differences between the arcs of the Northern (from Guadeloupe northward) and Southern (from Dominica southward) Lesser Antilles. Variations in earthquake activity between Haiti and the Dominican Republic can be explained by a change in slab geometry from an underplated slab beneath Haiti to a subducting slab under the Dominican Republic. A shallow tear in the slab may explain the anomalously deep Puerto Rico Trench and the frequent earthquake swarms there. The westward shift in volcanic activity in the Northern Lesser Antilles from the Miocene Limestone Caribbees to the present arc can be attributed to the limit on convective flow imposed by the 3-D geometry of the slab at depth. A thinned South America slab under the southern Lesser Antilles may result from traction imposed on the slab by a wide forearc wedge. Variations in tectonic deformation of northern South America could be related to the location of the Caribbean Large Igneous Province north of the Maracaibo Block.

  3. Signatures of downgoing plate-buoyancy driven subduction in Cenozoic plate motions

    NASA Astrophysics Data System (ADS)

    Goes, S.; Capitanio, F. A.; Morra, G.; Seton, M.; Giardini, D.

    2011-01-01

    The dynamics of plate tectonics are strongly related to those of subduction. To obtain a better understanding of the driving forces of subduction, we compare relations between Cenozoic subduction motions at major trenches with the trends expected for the simplest form of subduction. i.e., free subduction, driven solely by the buoyancy of the downgoing plate. In models with an Earth-like plate stiffness (corresponding to a plate-mantle viscosity contrast of 2-3 orders of magnitude), free plates subduct by a combination of downgoing plate motion and trench retreat, while the slab is draped and folded on top of the upper-lower mantle viscosity transition. In these models, the slabs sink according to their Stokes' velocities. Observed downgoing-plate motion-plate-age trends are compatible with >80% of the Cenozoic slabs sinking according to their upper-mantle Stokes' velocity, i.e., subducting-plate motion is largely driven by upper-mantle slab pull. Only in a few cases, do young plates move at velocities that require a higher driving force (possibly supplied by lower-mantle-slab induced flow). About 80% of the Cenozoic trenches retreat, with retreat accounting for about 10% of the total convergence. The few advancing trench sections are likely affected by regional factors. The low trench motions are likely encouraged by low asthenospheric drag (equivalent to that for effective asthenospheric viscosity 2-3 orders below the upper-mantle average), and low lithospheric strength (effective bending viscosity ˜2 orders of magnitude above the upper-mantle average). Total Cenozoic trench motions are often very oblique to the direction of downgoing-plate motion (mean angle of 73°). This indicates that other forces than slab buoyancy exert the main control on upper-plate/trench motion. However, the component of trench retreat in the direction of downgoing plate motion (≈ slab pull) correlates with downgoing-plate motion, and this component of retreat generally does not

  4. Towards modelling the evolution of intra plate stress: the Eurasian plate 20 Ma.

    NASA Astrophysics Data System (ADS)

    Quéré, Sandrine; Ruckstuhl, Karin; Wortel, Rinus; Govers, Rob; Hochard, Cyril; Stampfli, Gérard

    2010-05-01

    In this study, we investige the evolution of the intra plate stress field. We use the classical characterisation of forces acting regionally on a plate such as 'slab pull/suction', 'ridge push' and 'mantle drag' as used by Forsyth & Uyeda (1975), Chapple & Tullis (1977) and later by Wortel et al. (1991) and Govers & Meijer (2001). So far, the interaction between the lithosphere and the underlying mantle flow was oversimplified and implemented via a coupling cœfficient in the direction of the plate motion and we propose improving this specific interaction. As the shear stress field at the base of the plates is unknown in the past, we propose using a mantle flow simulation induced by the imposition of past plate motions on top of a 3D spherical mantle convective code. To that purpose, we employ the new plate motion reconstruction developed by Stampfli et al. (2008) and a 3D convective code where plates are dynamically coupled to the mantle (Quéré & Forte, 2006). The first plate on which we apply this method is the Eurasian plate as Eurasia is a large plate with a small velocity (not attached to its own subduction zone) and the debate on the main driving forces acting on Eurasia is still going on. The stress field 20 Ma resulting from all plate tectonic forces is calculated by assuming mechanical equilibrium in an homogeneous elastic shell using the plane stress approximation. As direct stress indicators for the past are rare, the predicted paleo-stress field is compared to pertinent data from orogens and extensional basins which will provide new clues to oil exploration teams.

  5. 21 CFR 882.4030 - Skull plate anvil.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Skull plate anvil. 882.4030 Section 882.4030 Food... DEVICES NEUROLOGICAL DEVICES Neurological Surgical Devices § 882.4030 Skull plate anvil. (a) Identification. A skull plate anvil is a device used to form alterable skull plates in the proper shape to...

  6. 21 CFR 882.4030 - Skull plate anvil.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Skull plate anvil. 882.4030 Section 882.4030 Food... DEVICES NEUROLOGICAL DEVICES Neurological Surgical Devices § 882.4030 Skull plate anvil. (a) Identification. A skull plate anvil is a device used to form alterable skull plates in the proper shape to...

  7. 21 CFR 882.4030 - Skull plate anvil.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Skull plate anvil. 882.4030 Section 882.4030 Food... DEVICES NEUROLOGICAL DEVICES Neurological Surgical Devices § 882.4030 Skull plate anvil. (a) Identification. A skull plate anvil is a device used to form alterable skull plates in the proper shape to...

  8. 21 CFR 882.4030 - Skull plate anvil.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Skull plate anvil. 882.4030 Section 882.4030 Food... DEVICES NEUROLOGICAL DEVICES Neurological Surgical Devices § 882.4030 Skull plate anvil. (a) Identification. A skull plate anvil is a device used to form alterable skull plates in the proper shape to...

  9. 21 CFR 882.4030 - Skull plate anvil.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Skull plate anvil. 882.4030 Section 882.4030 Food... DEVICES NEUROLOGICAL DEVICES Neurological Surgical Devices § 882.4030 Skull plate anvil. (a) Identification. A skull plate anvil is a device used to form alterable skull plates in the proper shape to...

  10. 46 CFR 154.170 - Outer hull steel plating.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 false Outer hull steel plating. 154.170 Section 154.170... Structure § 154.170 Outer hull steel plating. (a) Except as required in paragraph (b) of this section, the outer hull steel plating, including the shell and deck plating must meet the material standards of...

  11. 46 CFR 154.170 - Outer hull steel plating.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 5 2013-10-01 2013-10-01 false Outer hull steel plating. 154.170 Section 154.170... Structure § 154.170 Outer hull steel plating. (a) Except as required in paragraph (b) of this section, the outer hull steel plating, including the shell and deck plating must meet the material standards of...

  12. 46 CFR 154.170 - Outer hull steel plating.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 5 2012-10-01 2012-10-01 false Outer hull steel plating. 154.170 Section 154.170... Structure § 154.170 Outer hull steel plating. (a) Except as required in paragraph (b) of this section, the outer hull steel plating, including the shell and deck plating must meet the material standards of...

  13. 46 CFR 154.170 - Outer hull steel plating.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false Outer hull steel plating. 154.170 Section 154.170... Structure § 154.170 Outer hull steel plating. (a) Except as required in paragraph (b) of this section, the outer hull steel plating, including the shell and deck plating must meet the material standards of...

  14. 49 CFR 451.21 - Safety approval plate required.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 6 2012-10-01 2012-10-01 false Safety approval plate required. 451.21 Section 451... HOMELAND SECURITY SAFETY APPROVAL OF CARGO CONTAINERS TESTING AND APPROVAL OF CONTAINERS Safety Approval Plate § 451.21 Safety approval plate required. (a) The safety approval plate must be supplied by...

  15. Making More Efficient Use Of Battery-Plate Mass

    NASA Technical Reports Server (NTRS)

    Rowlette, John J.

    1990-01-01

    Improved active material for positive plate of lead/acid electric storage battery made with additional porosity to give electrolyte access to larger plate-surface area. 65 to 68 percent of active mass of plate used to generate electric current. Batteries with new plate material offer extremely long cycle life.

  16. A unified theory for laminated plates

    NASA Astrophysics Data System (ADS)

    Guiamatsia Tafeuvoukeng, Irene

    A literature survey on plate and beam theories show how the advent of the finite element method and the variational method circa 1940 have been a great stimulant for the research in this field. The initial thin plate formulation has been incrementally expanded to treat the isotropic thick plate, the anisotropic single layer, and then laminated plates. It appears however that current formulations still fall into one of two categories: (1) The formulation is tailored for a specific laminate and/or loading case; (2) or the formulation is too complicated to be of practical relevance. In this work a new unifying approach to laminated plate formulation is presented. All laminated plates, including sandwich panels, subjected to any surface load and with any boundary conditions are treated within a single model. In addition, the fundamental behavior of the plate as a two-dimensional structural element is explained. The novel idea is the introduction of fundamental state solutions, which are analytical far field stress and strain solutions of the laminated plate subjected to a set of hierarchical primary loads, the fundamental loads. These loads are carefully selected to form a basis of the load space, and corresponding solutions are superposed to obtain extremely accurate predictions of the three dimensional solution. six,y,z =aklx,y sikl z where i = 1,..., 6; 1=1,...,l max is a substate of the kth fundamental state k=1,2,3,... Typically, a fundamental state solution is expressed as a through-thickness function (z), while the amplitudes of each fundamental load are found from two dimensional finite element solution as a function of in-plane coordinates (x,y). Three major contributions are produced in this work: (1) A complete calibration of the plate as a two-dimensional structure is performed with pure bending and constant shear fundamental states. (2) There are four independent ways to apply a constant shear resultant on a plate, as opposed to one for a beam. This makes

  17. Spirit Begins Drive Around Home Plate

    NASA Technical Reports Server (NTRS)

    2009-01-01

    The hazard avoidance camera on the front of NASA's Mars Exploration Rover Spirit took this image after a drive by Spirit on the 1,829th Martian day, or sol, of Spirit's mission on the surface of Mars (Feb. 24, 2009).

    On Sol 1829, Spirit drove 6.29 meters (21 feet) northwestward, away from the northern edge of the low plateau called 'Home Plate.' The track dug by the dragged right-front wheel as the rover drove backward is visible in this image, receding toward the southeast. Rock layers of the northern slope of Home Plate are visible in the upper right portion of the image.

    In sols prior to 1829, the rover team had been trying to maneuver Spirit to climb onto the northern edge of Home Plate, ready to drive southward across the top of the plateau toward science destinations south of Home Plate. The Sol 1829 drive was the first move of a revised strategy to circle at least partway around Home Plate on the trek toward the sites south of the plateau.

  18. Recovery process for electroless plating baths

    DOEpatents

    Anderson, R.W.; Neff, W.A.

    1992-05-12

    A process is described for removing, from spent electroless metal plating bath solutions, accumulated byproducts and counter-ions that have deleterious effects on plating. The solution, or a portion thereof, is passed through a selected cation exchange resin bed in hydrogen form, the resin selected from strong acid cation exchangers and combinations of intermediate acid cation exchangers with strong acid cation exchangers. Sodium and nickel ions are sorbed in the selected cation exchanger, with little removal of other constituents. The remaining solution is subjected to sulfate removal through precipitation of calcium sulfate hemihydrate using, sequentially, CaO and then CaCO[sub 3]. Phosphite removal from the solution is accomplished by the addition of MgO to form magnesium phosphite trihydrate. The washed precipitates of these steps can be safely discarded in nontoxic land fills, or used in various chemical industries. Finally, any remaining solution can be concentrated, adjusted for pH, and be ready for reuse. The plating metal can be removed from the exchanger with sulfuric acid or with the filtrate from the magnesium phosphite precipitation forming a sulfate of the plating metal for reuse. The process is illustrated as applied to processing electroless nickel plating baths. 18 figs.

  19. Recovery process for electroless plating baths

    DOEpatents

    Anderson, Roger W.; Neff, Wayne A.

    1992-01-01

    A process for removing, from spent electroless metal plating bath solutions, accumulated byproducts and counter-ions that have deleterious effects on plating. The solution, or a portion thereof, is passed through a selected cation exchange resin bed in hydrogen form, the resin selected from strong acid cation exchangers and combinations of intermediate acid cation exchangers with strong acid cation exchangers. Sodium and nickel ions are sorbed in the selected cation exchanger, with little removal of other constituents. The remaining solution is subjected to sulfate removal through precipitation of calcium sulfate hemihydrate using, sequentially, CaO and then CaCO.sub.3. Phosphite removal from the solution is accomplished by the addition of MgO to form magnesium phosphite trihydrate. The washed precipitates of these steps can be safely discarded in nontoxic land fills, or used in various chemical industries. Finally, any remaining solution can be concentrated, adjusted for pH, and be ready for reuse. The plating metal can be removed from the exchanger with sulfuric acid or with the filtrate from the magnesium phosphite precipitation forming a sulfate of the plating metal for reuse. The process is illustrated as applied to processing electroless nickel plating baths.

  20. Flow structure on a rotating plate

    NASA Astrophysics Data System (ADS)

    Ozen, C. A.; Rockwell, D.

    2012-01-01

    The flow structure on a rotating plate of low aspect ratio is characterized well after the onset of motion, such that transient effects are not significant, and only centripetal and Coriolis accelerations are present. Patterns of vorticity, velocity contours, and streamline topology are determined via quantitative imaging, in order to characterize the leading-edge vortex in relation to the overall flow structure. A stable leading-edge vortex is maintained over effective angles of attack from 30° to 75°, and at each angle of attack, its sectional structure at midspan is relatively insensitive to Reynolds number over the range from 3,600 to 14,500. The streamline topology, vorticity distribution, and circulation of the leading-edge vortex are determined as a function of angle of attack, and related to the velocity field oriented toward, and extending along, the leeward surface of the plate. The structure of the leading-edge vortex is classified into basic regimes along the span of the plate. Images of these regimes are complemented by patterns on crossflow planes, which indicate the influence of root and tip swirl, and spanwise flow along the leeward surface of the plate. Comparison with the equivalent of the purely translating plate, which does not induce the foregoing flow structure, further clarifies the effects of rotation.

  1. Computer animation of Phanerozoic plate motions

    SciTech Connect

    Scotese, C.R. . Dept. of Geology)

    1992-01-01

    Since 1985, the PALEOMAP Project, in collaboration with research groups both in the US and abroad, has assembled a digital model that describes global plate motions during the last 600 million years. In this paper the authors present a series of computer animations that dynamically illustrates the movement of continents and terranes, and the evolution of the ocean basins since the breakup of the late Precambrian supercontinent. These animations depict the motion of the plates from both equatorial and polar perspectives. Mesozoic and Cenozoic plate tectonic reconstructions are based on a synthesis of linear magnetic anomalies, fracture zone locations, intracontinental rifts, collision and thrust belts, and zones of strike-slip. Paleozoic plate reconstructions, though more speculative, are based on evidence of past subduction, continental collision, and inferred sea floor spreading. The relative longitudinal positions of the continents during the Paleozoic and the width of intervening oceans have been adjusted to best explain changing biogeographic and paleoclimatic patterns. A new paleomagnetic/hot spot reference frame has been constructed that combines paleomagnetic data compiled by Rob Van der Voo (1992) with inferred motion relative to a fixed frame of hot spots. Using probable Early Mesozoic and Paleozoic hot spot tracks on the major continents, the authors have extended plate motions relative to the hot spot reference frame back to 400 million years.

  2. Extreme Wave Impact on a Flexible Plate

    NASA Astrophysics Data System (ADS)

    Abraham, Aliza; Techet, Alexandra

    2015-11-01

    Digital image correlation (DIC) and particle image velocimetry (PIV) are combined to characterize the flow-structure interaction of a breaking wave impacting a flexible vertically mounted plate. DIC is used with the beam bending equation to determine the stresses on the plate and PIV is used to describe the flow of the wave. In this experiment, a simulated dam break in which water is rapidly released from a reservoir generates the wave, which impinges on a cantilevered stainless steel plate downstream. Pressure sensors mounted on the plate are used to gather further information about the forces acting on it. A series of waves of different heights and breaking locations are tested, controlled by the volume of water in the tank and the volume of water in the dam break reservoir. The deflection of the plate varies depending on the point of breaking and the height of the wave. These results shed light on the effect of breaking wave impacts on offshore structures and ship hulls.

  3. Rotary sequencing valve with flexible port plate

    DOEpatents

    Wagner, Glenn Paul

    2005-05-10

    Rotary sequencing valve comprising a rotor having a rotor face rotatable about an axis perpendicular to the rotor face, wherein the rotor face has a plurality of openings, one or more of which are disposed at a selected radial distance from the axis, and wherein the rotor includes at least one passage connecting at least one pair of the plurality of openings. The valve includes a flexible port plate having a first side and a second side, wherein the first side faces the rotor and engages the rotor such that the flexible port plate can be rotated coaxially by the rotor and can move axially with respect to the rotor, wherein the flexible port plate has a plurality of ports between the first and second sides, which ports are aligned with the openings in the rotor face. The valve also includes a stator having a stator face disposed coaxially with the rotor and the flexible port plate, wherein the second side of the flexible port plate is in sealable, slidable rotary contact with the stator face, wherein the stator face has a plurality of openings, some of which are disposed at the selected radial distance from the axis, and wherein the plurality of openings extend as passages through the stator. The valve may be used in pressure or temperature swing adsorption systems.

  4. Geometrically nonlinear behavior of piezoelectric laminated plates

    NASA Astrophysics Data System (ADS)

    Rabinovitch, Oded

    2005-08-01

    The geometrically nonlinear behavior of piezo-laminated plates actuated with isotropic or anisotropic piezoelectric layers is analytically investigated. The analytical model is derived using the variational principle of virtual work along with the lamination and plate theories, the von Karman large displacement and moderate rotation kinematic relations, and the anisotropic piezoelectric constitutive laws. A solution strategy that combines the approach of the method of lines, the advantages of the finite element concept, and the variational formulation is developed. This approach yields a set of nonlinear ordinary differential equations with nonlinear boundary conditions, which are solved using the multiple-shooting method. Convergence and verification of the model are examined through comparison with linear and nonlinear results of other approximation methods. The nonlinear response of two active plate structures is investigated numerically. The first plate is actuated in bending using monolithic piezoceramic layers and the second one is actuated in twist using macro-fiber composites. The results quantitatively reveal the complicated in-plane stress state associated with the piezoelectric actuation and the geometrically nonlinear coupling of the in-plane and out-of-plane responses of the plate. The influence of the nonlinear effects ranges from significant stiffening in certain combinations of electrical loads and boundary conditions to amplifications of the induced deflections in others. The paper closes with a summary and conclusions.

  5. Preserving and Archiving Astronomical Photographic Plates

    NASA Astrophysics Data System (ADS)

    Castelaz, M. W.; Cline, J. D.

    2005-05-01

    Astronomical objects change with time. New observations complement past observations recorded on photographic plates. Analyses of changes provide essential routes to information about an object's formation, constitution and evolution. Preserving a century of photographic plate observations is thus of paramount importance. Plate collections are presently widely dispersed; plates may be stored in poor conditions, and are effectively inaccessible to both researchers and historians. We describe a planned project at Pisgah Astronomical Research Institute to preserve the collections of astronomical plates in the United States by gathering them into a single storage location. Collections will be sorted, cleaned, and cataloged on-line so as to provide access to researchers. Full scientific and historic use of the material then requires the observations themselves to be accessible digitally. The project's goal will be the availability of these data as a unique, fully-maintained scientific and educational resource. The new archive will support trans-disciplinary research such as the chemistry of the Earth's atmosphere, library information science, trends in local weather patterns, and impacts of urbanization on telescope use, while the hand-written observatory logs will be a valuable resource for science historians and biographers.

  6. Ridge push engine of plate tectonics

    NASA Astrophysics Data System (ADS)

    Swedan, N. H.

    2015-07-01

    Convection of the upper mantle drives the tectonic plates. This convection is a thermodynamic cycle that exchanges heat and mechanical work between mantle and tectonic plates. Thermodynamics and observations indicate that the energy of the geological activities resulting from plate tectonics is equal to the latent heat of melting, calculated at mantle's pressure, of the new ocean crust regenerated at midocean ridges. This energy varies with the temperature of ocean floor, which is correlated with surface temperature. The main objective of this manuscript is to demonstrate that plate tectonics is a thermodynamic engine and can be calculated as such. Unlike existing tectonic models, the thermodynamic model is very sensitive to variations of the temperature of ocean floor, which is correlated with surface temperature. Therefore, the observed increase of geological activities can be projected with surface temperature rise. Other objectives of the manuscript are to calculate the force that drives the tectonic plates, estimate the energy released, and validate the calculations based on experiments and observations. In addition to the scientific merit of projecting the geological activities, a good projection can have a broader impact at the societal and economical levels. Investment and insurance related decisions are affected by climate change, and our ability to project the geological activities is of paramount importance for the economy and public safety. This work can thus provide tools to assess the risks and hazards associated with the trend of geological activities with surface temperature rise.

  7. Finite element analysis of advanced neutron source fuel plates

    SciTech Connect

    Luttrell, C.R.

    1995-08-01

    The proposed design for the Advanced Neutron Source reactor core consists of closely spaced involute fuel plates. Coolant flows between the plates at high velocities. It is vital that adjacent plates do not come in contact and that the coolant channels between the plates remain open. Several scenarios that could result in problems with the fuel plates are studied. Finite element analyses are performed on fuel plates under pressure from the coolant flowing between the plates at a high velocity, under pressure because of a partial flow blockage in one of the channels, and with different temperature profiles.

  8. Current plate motions. [continental groupings and global modelling

    NASA Technical Reports Server (NTRS)

    Demets, C.; Gordon, R. G.; Argus, D. F.; Stein, S.

    1990-01-01

    A global plate motion model, named NUVEL-1, which describes current plate motions between 12 rigid plates is described, with special attention given to the method, data, and assumptions used. Tectonic implications of the patterns that emerged from the results are discussed. It is shown that wide plate boundary zones can form not only within the continental lithosphere but also within the oceanic lithosphere; e.g., between the Indian and Australian plates and between the North American and South American plates. Results of the model also suggest small but significant diffuse deformation of the oceanic lithosphere, which may be confined to small awkwardly shaped salients of major plates.

  9. Finite element modeling of stress in the Nazca plate - Driving forces and plate boundary earthquakes

    NASA Technical Reports Server (NTRS)

    Richardson, R. M.

    1978-01-01

    The state of stress within the Nazca plate due to plate driving forces and large plate boundary earthquakes has been analyzed by applying a finite element method using the wave front solution technique to models of the intraplate stress field in a single plate using a refined grid. Although only static elastic models have been explicitly calculated, certain limiting cases of an elastic plate over a viscous asthenosphere were also treated. A state of nearly east-west compression inferred from the source mechanism of thrust earthquakes in the interior of the plate requires ridge pushing forces. The net pulling force on the oceanic plate by the subducted slab has a maximum value comparable to pushing forces. The estimated horizontal deviatoric stress in intraplate regions, based on potential forces associated with the ridge, is on the order of a few hundred bars. The intraplate stress field in the region of the 1960 earthquake may change by a few tens of bars at most once the asthenosphere has relaxed, with changes on the order of one bar occurring at greater distances into the plate. The changes in the intraplate stress field are probably not noticeable unless the lithosphere is near failure.

  10. Lasting mantle scars lead to perennial plate tectonics

    PubMed Central

    Heron, Philip J.; Pysklywec, Russell N.; Stephenson, Randell

    2016-01-01

    Mid-ocean ridges, transform faults, subduction and continental collisions form the conventional theory of plate tectonics to explain non-rigid behaviour at plate boundaries. However, the theory does not explain directly the processes involved in intraplate deformation and seismicity. Recently, damage structures in the lithosphere have been linked to the origin of plate tectonics. Despite seismological imaging suggesting that inherited mantle lithosphere heterogeneities are ubiquitous, their plate tectonic role is rarely considered. Here we show that deep lithospheric anomalies can dominate shallow geological features in activating tectonics in plate interiors. In numerical experiments, we found that structures frozen into the mantle lithosphere through plate tectonic processes can behave as quasi-plate boundaries reactivated under far-field compressional forcing. Intraplate locations where proto-lithospheric plates have been scarred by earlier suturing could be regions where latent plate boundaries remain, and where plate tectonics processes are expressed as a ‘perennial' phenomenon. PMID:27282541

  11. Lasting mantle scars lead to perennial plate tectonics.

    PubMed

    Heron, Philip J; Pysklywec, Russell N; Stephenson, Randell

    2016-01-01

    Mid-ocean ridges, transform faults, subduction and continental collisions form the conventional theory of plate tectonics to explain non-rigid behaviour at plate boundaries. However, the theory does not explain directly the processes involved in intraplate deformation and seismicity. Recently, damage structures in the lithosphere have been linked to the origin of plate tectonics. Despite seismological imaging suggesting that inherited mantle lithosphere heterogeneities are ubiquitous, their plate tectonic role is rarely considered. Here we show that deep lithospheric anomalies can dominate shallow geological features in activating tectonics in plate interiors. In numerical experiments, we found that structures frozen into the mantle lithosphere through plate tectonic processes can behave as quasi-plate boundaries reactivated under far-field compressional forcing. Intraplate locations where proto-lithospheric plates have been scarred by earlier suturing could be regions where latent plate boundaries remain, and where plate tectonics processes are expressed as a 'perennial' phenomenon. PMID:27282541

  12. Lasting mantle scars lead to perennial plate tectonics

    NASA Astrophysics Data System (ADS)

    Heron, Philip J.; Pysklywec, Russell N.; Stephenson, Randell

    2016-06-01

    Mid-ocean ridges, transform faults, subduction and continental collisions form the conventional theory of plate tectonics to explain non-rigid behaviour at plate boundaries. However, the theory does not explain directly the processes involved in intraplate deformation and seismicity. Recently, damage structures in the lithosphere have been linked to the origin of plate tectonics. Despite seismological imaging suggesting that inherited mantle lithosphere heterogeneities are ubiquitous, their plate tectonic role is rarely considered. Here we show that deep lithospheric anomalies can dominate shallow geological features in activating tectonics in plate interiors. In numerical experiments, we found that structures frozen into the mantle lithosphere through plate tectonic processes can behave as quasi-plate boundaries reactivated under far-field compressional forcing. Intraplate locations where proto-lithospheric plates have been scarred by earlier suturing could be regions where latent plate boundaries remain, and where plate tectonics processes are expressed as a `perennial' phenomenon.

  13. Performance evaluation of the R6R018 fuel plate using PLATE code

    SciTech Connect

    Pavel G. Medvedev; Hakan Ozaltun

    2010-03-01

    The paper presents results of performance evaluation of the R6R018 fuel plate using PLATE code. R6R018 is a U-7Mo dispersion type mini-plate with Al-3.5Si matrix irradiated in the RERTR-9B experiment. The design of this plate is prototypical of the planned LEONIDAS irradiation test. Therefore, a detailed performance analysis of this plate is important to confirm acceptable behavior in pile, and to provide baseline and justification for further analysis and testing. Specific results presented in the paper include fuel temperature history, growth of the interaction layer between the U-Mo and the matrix, swelling, growth of the corrosion layer, and degradation of thermal conductivity. The methodology of the analysis will be discussed including the newly developed capability to account for the formation of the interaction layer during fuel fabrication.

  14. Nonlocal third-order shear deformation plate theory with application to bending and vibration of plates

    NASA Astrophysics Data System (ADS)

    Aghababaei, Ramin; Reddy, J. N.

    2009-09-01

    The third-order shear deformation plate theory of Reddy [A simple higher-order theory for laminated composite plates, J. Appl. Mech. 51 (1984) 745-752] is reformulated using the nonlocal linear elasticity theory of Eringen. This theory has ability to capture the both small scale effects and quadratic variation of shear strain and consequently shear stress through the plate thickness. Analytical solutions of bending and free vibration of a simply supported rectangular plate are presented using this theory to illustrate the effect of nonlocal theory on deflection and natural frequency of the plates. Finally, the relations between nonlocal third-order, first-order and classical theories are discussed by numerical results.

  15. Highly conductive composites for fuel cell flow field plates and bipolar plates

    DOEpatents

    Jang, Bor Z; Zhamu, Aruna; Song, Lulu

    2014-10-21

    This invention provides a fuel cell flow field plate or bipolar plate having flow channels on faces of the plate, comprising an electrically conductive polymer composite. The composite is composed of (A) at least 50% by weight of a conductive filler, comprising at least 5% by weight reinforcement fibers, expanded graphite platelets, graphitic nano-fibers, and/or carbon nano-tubes; (B) polymer matrix material at 1 to 49.9% by weight; and (C) a polymer binder at 0.1 to 10% by weight; wherein the sum of the conductive filler weight %, polymer matrix weight % and polymer binder weight % equals 100% and the bulk electrical conductivity of the flow field or bipolar plate is at least 100 S/cm. The invention also provides a continuous process for cost-effective mass production of the conductive composite-based flow field or bipolar plate.

  16. Plate on plate osteosynthesis for the treatment of nonhealed periplate fractures.

    PubMed

    Arealis, Georgios; Nikolaou, Vassilios S; Lacon, Andrew; Ashwood, Neil; Hamlet, Mark

    2014-01-01

    Purpose. The purpose of this paper is to present our technique for the treatment of periplate fractures. Methods. From 2009 to 2012 we treated three patients. In all cases the existing plate was left and the new one placed over the existing. Locking screws were placed through both plates. The other screws in the new plate were used as best suited the fracture. Results. In all cases less than 6 months had passed between fractures. None of the original fractures had healed. Mean followup was 2 years. All fractures proceeded to union within 7 months. No complications were recorded. All the patients returned to their normal activities and were satisfied with the results of their treatment. Conclusion. Our plate on plate technique is effective for the treatment of periplate fractures. A solid fusion can be achieved at the new fracture site without disturbing the previous fixation. PMID:24967127

  17. 49 CFR 179.200-6 - Thickness of plates.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... bursting pressure in psig; S = Minimum tensile strength of plate material in p.s.i. as prescribed in § 179... strength of plate material in p.s.i. as prescribed in § 179.200-7; t = Minimum thickness of plate in inches... strength of plate material in p.s.i. as prescribed in § 179.200-7; t = Minimum thickness of plate in...

  18. 49 CFR 179.200-6 - Thickness of plates.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... bursting pressure in psig; S = Minimum tensile strength of plate material in p.s.i. as prescribed in § 179... strength of plate material in p.s.i. as prescribed in § 179.200-7; t = Minimum thickness of plate in inches... strength of plate material in p.s.i. as prescribed in § 179.200-7; t = Minimum thickness of plate in...

  19. 49 CFR 179.200-6 - Thickness of plates.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... bursting pressure in psig; S = Minimum tensile strength of plate material in p.s.i. as prescribed in § 179... strength of plate material in p.s.i. as prescribed in § 179.200-7; t = Minimum thickness of plate in inches... strength of plate material in p.s.i. as prescribed in § 179.200-7; t = Minimum thickness of plate in...

  20. 49 CFR 179.200-6 - Thickness of plates.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... bursting pressure in psig; S = Minimum tensile strength of plate material in p.s.i. as prescribed in § 179... strength of plate material in p.s.i. as prescribed in § 179.200-7; t = Minimum thickness of plate in inches... strength of plate material in p.s.i. as prescribed in § 179.200-7; t = Minimum thickness of plate in...

  1. Root-Contact/Pressure-Plate Assembly For Hydroponic System

    NASA Technical Reports Server (NTRS)

    Morris, Carlton E.; Loretan, Philip A.; Bonsi, Conrad K.; Hill, Walter A.

    1994-01-01

    Hydroponic system includes growth channels equipped with rootcontact/pressure-plate assemblies. Pump and associated plumbing circulate nutrient liquid from reservoir, along bottom of growth channels, and back to reservoir. Root-contact/pressure-plate assembly in each growth channel stimulates growth of roots by applying mild contact pressure. Flat plate and plate connectors, together constitute pressure plate, free to move upward to accommodate growth of roots. System used for growing sweetpotatoes and possibly other tuber and root crops.

  2. Optical Analyzer Technique for Spall Investigations in Metal Plates

    SciTech Connect

    Kovalenko, G. V.; Kozlov, E. A.; Nogin, V. N.; Pankratov, D. G.; Yakunin, A. K.

    2006-08-03

    Possible experimental set-up for investigation of the stage of spalls closing in plates before impact on base plate are considered. Multi-wave configurations in indicator-matter situated on the base plate are observed by optical analyzer technique. Oscillograms and results of their processing are presented. Thickness and average density of the spall layer in the plate immediately before its impact on the base plate are estimated.

  3. Microporous microchannel plates and method of manufacturing same

    DOEpatents

    Beetz, Jr., Charles P.; Boerstler, Robert W.; Steinbeck, John; Winn, David R.

    2000-01-01

    A microchannel plate and method of manufacturing same is provided. The microchannel plate includes a plate consisting of an anodized material and a plurality of channels which are formed during the anodization of the material and extend between the two sides of the plate. Electrodes are also disposed on each side of the plate for generating an electrical field within the channels. Preferably, the material is alumina and the channels are activated such that the channel walls are conductive and highly secondary emissive.

  4. Supracondylar Osteotomy in Valgus Knee: Angle Blade Plate Versus Locking Compression Plate

    PubMed Central

    Kazemi, Seyyed Morteza; Minaei, Reza; Safdari, Farshad; Keipourfard, Ali; Forghani, Rozhin; Mirzapourshafiei, Alemeh

    2016-01-01

    Background: There are few studies comparing the biomechanical properties of angled blade plate and locking compression plates in supracondylar osteotomy. In the current randomized study, we prospectively compared the clinical and radiological outcomes of supracondylar osteotomy using these two plates. Methods: Forty patients with valgus knee malalignment were randomly assigned to two equal numbered groups: angled blade plate and locking compression plates. All of the patients underwent medial closing wedge supracondylar osteotomy and were followed for one year. Before and after the operation the valgus angle and mechanical lateral distal femoral angle were compared between groups. Also, the rate of complications were compared. Results: After the operation, the mean valgus angle and mechanical lateral distal femoral angle improved significantly in the two groups (P<0.001). Although, the preoperative amount of the valgus angle and mechanical lateral distal femoral angle were the same, at the last visit the valgus angle (5.4±2.1 versus 3.1±1.8; P=0.032) and mechanical lateral distal femoral angle (87.6±2 versus 89.7±3.2; P=0.041) were significantly lower and higher in the angled blade plate group, respectively. Nonunion occurred in four patients (20%) in the locking compression plates group (P=0.35). Conclusion: Based on having a larger valgus angle and mechanical lateral distal femoral angle correction in the angled blade plate group and considerable rate of nonunion in the locking compression plate group, the authors recommend using the angled blade plate for fixation of medial closing wedge supracondylar osteotomy for patients with valgus malalignment. However, more long-term studies are required. PMID:26894215

  5. Dual fuel gradients in uranium silicide plates

    SciTech Connect

    Pace, B.W.

    1997-08-01

    Babcock & Wilcox has been able to achieve dual gradient plates with good repeatability in small lots of U{sub 3}Si{sub 2} plates. Improvements in homogeneity and other processing parameters and techniques have allowed the development of contoured fuel within the cladding. The most difficult obstacles to overcome have been the ability to evaluate the bidirectional fuel loadings in comparison to the perfect loading model and the different methods of instilling the gradients in the early compact stage. The overriding conclusion is that to control the contour of the fuel, a known relationship between the compact, the frames and final core gradient must exist. Therefore, further development in the creation and control of dual gradients in fuel plates will involve arriving at a plausible gradient requirement and building the correct model between the compact configuration and the final contoured loading requirements.

  6. Flow of nanofluid past a Riga plate

    NASA Astrophysics Data System (ADS)

    Ahmad, Adeel; Asghar, Saleem; Afzal, Sumaira

    2016-03-01

    This paper studies the mixed convection boundary layer flow of a nanofluid past a vertical Riga plate in the presence of strong suction. The mathematical model incorporates the Brownian motion and thermophoresis effects due to nanofluid and the Grinberg-term for the wall parallel Lorentz force due to Riga plate. The analytical solution of the problem is presented using the perturbation method for small Brownian and thermophoresis diffusion parameters. The numerical solution is also presented to ensure the reliability of the asymptotic method. The comparison of the two solutions shows an excellent agreement. The correlation expressions for skin friction, Nusselt number and Sherwood number are developed by performing linear regression on the obtained numerical data. The effects of nanofluid and the Lorentz force due to Riga plate, on the skin friction are discussed.

  7. Astrometric properties of the Tautenburg Plate Scanner

    NASA Astrophysics Data System (ADS)

    Brunzendorf, Jens; Meusinger, Helmut

    The Tautenburg Plate Scanner (TPS) is an advanced plate-measuring machine run by the Thüringer Landessternwarte Tautenburg (Karl Schwarzschild Observatory), where the machine is housed. It is capable of digitising photographic plates up to 30 cm × 30 cm in size. In our poster, we reported on tests and preliminary results of its astrometric properties. The essential components of the TPS consist of an x-y table movable between an illumination system and a direct imaging system. A telecentric lens images the light transmitted through the photographic emulsion onto a CCD line of 6000 pixels of 10 µm square size each. All components are mounted on a massive air-bearing table. Scanning is performed in lanes of up to 55 mm width by moving the x-y table in a continuous drift-scan mode perpendicular to the CCD line. The analogue output from the CCD is digitised to 12 bit with a total signal/noise ratio of 1000 : 1, corresponding to a photographic density range of three. The pixel map is produced as a series of optionally overlapping lane scans. The pixel data are stored onto CD-ROM or DAT. A Tautenburg Schmidt plate 24 cm × 24 cm in size is digitised within 2.5 hours resulting in 1.3 GB of data. Subsequent high-level data processing is performed off-line on other computers. During the scanning process, the geometry of the optical components is kept fixed. The optimal focussing of the optics is performed prior to the scan. Due to the telecentric lens refocussing is not required. Therefore, the main source of astrometric errors (beside the emulsion itself) are mechanical imperfections in the drive system, which have to be divided into random and systematic ones. The r.m.s. repeatability over the whole plate as measured by repeated scans of the same plate is about 0.5 µm for each axis. The mean plate-to-plate accuracy of the object positions on two plates with the same epoch and the same plate centre has been determined to be about 1 µm. This accuracy is comparable to

  8. Plate tectonics drive tropical reef biodiversity dynamics

    PubMed Central

    Leprieur, Fabien; Descombes, Patrice; Gaboriau, Théo; Cowman, Peter F.; Parravicini, Valeriano; Kulbicki, Michel; Melián, Carlos J.; de Santana, Charles N.; Heine, Christian; Mouillot, David; Bellwood, David R.; Pellissier, Loïc

    2016-01-01

    The Cretaceous breakup of Gondwana strongly modified the global distribution of shallow tropical seas reshaping the geographic configuration of marine basins. However, the links between tropical reef availability, plate tectonic processes and marine biodiversity distribution patterns are still unknown. Here, we show that a spatial diversification model constrained by absolute plate motions for the past 140 million years predicts the emergence and movement of diversity hotspots on tropical reefs. The spatial dynamics of tropical reefs explains marine fauna diversification in the Tethyan Ocean during the Cretaceous and early Cenozoic, and identifies an eastward movement of ancestral marine lineages towards the Indo-Australian Archipelago in the Miocene. A mechanistic model based only on habitat-driven diversification and dispersal yields realistic predictions of current biodiversity patterns for both corals and fishes. As in terrestrial systems, we demonstrate that plate tectonics played a major role in driving tropical marine shallow reef biodiversity dynamics. PMID:27151103

  9. Numerical modelling of instantaneous plate tectonics

    NASA Technical Reports Server (NTRS)

    Minster, J. B.; Haines, E.; Jordan, T. H.; Molnar, P.

    1974-01-01

    Assuming lithospheric plates to be rigid, 68 spreading rates, 62 fracture zones trends, and 106 earthquake slip vectors are systematically inverted to obtain a self-consistent model of instantaneous relative motions for eleven major plates. The inverse problem is linearized and solved iteratively by a maximum-likelihood procedure. Because the uncertainties in the data are small, Gaussian statistics are shown to be adequate. The use of a linear theory permits (1) the calculation of the uncertainties in the various angular velocity vectors caused by uncertainties in the data, and (2) quantitative examination of the distribution of information within the data set. The existence of a self-consistent model satisfying all the data is strong justification of the rigid plate assumption. Slow movement between North and South America is shown to be resolvable.

  10. Plate tectonics drive tropical reef biodiversity dynamics.

    PubMed

    Leprieur, Fabien; Descombes, Patrice; Gaboriau, Théo; Cowman, Peter F; Parravicini, Valeriano; Kulbicki, Michel; Melián, Carlos J; de Santana, Charles N; Heine, Christian; Mouillot, David; Bellwood, David R; Pellissier, Loïc

    2016-01-01

    The Cretaceous breakup of Gondwana strongly modified the global distribution of shallow tropical seas reshaping the geographic configuration of marine basins. However, the links between tropical reef availability, plate tectonic processes and marine biodiversity distribution patterns are still unknown. Here, we show that a spatial diversification model constrained by absolute plate motions for the past 140 million years predicts the emergence and movement of diversity hotspots on tropical reefs. The spatial dynamics of tropical reefs explains marine fauna diversification in the Tethyan Ocean during the Cretaceous and early Cenozoic, and identifies an eastward movement of ancestral marine lineages towards the Indo-Australian Archipelago in the Miocene. A mechanistic model based only on habitat-driven diversification and dispersal yields realistic predictions of current biodiversity patterns for both corals and fishes. As in terrestrial systems, we demonstrate that plate tectonics played a major role in driving tropical marine shallow reef biodiversity dynamics. PMID:27151103

  11. Caribbean tectonics and relative plate motions

    NASA Technical Reports Server (NTRS)

    Burke, K.; Dewey, J. F.; Cooper, C.; Mann, P.; Pindell, J. L.

    1984-01-01

    During the last century, three different ways of interpreting the tectonic evolution of the Gulf of Mexico and the Caribbean have been proposed, taking into account the Bailey Willis School of a permanent pre-Jurassic deep sea basin, the Edward Suess School of a subsided continental terrain, and the Alfred Wegener School of continental separation. The present investigation is concerned with an outline of an interpretation which follows that of Pindell and Dewey (1982). An attempt is made to point out ways in which the advanced hypotheses can be tested. The fit of Africa, North America, and South America is considered along with aspects of relative motion between North and South America since the early Jurasic. Attention is given to a framework for reconstructing Caribbean plate evolution, the evolution of the Caribbean, the plate boundary zones of the northern and southern Caribbean, and the active deformation of the Caribbean plate.

  12. On the dip angle of subducting plates

    NASA Technical Reports Server (NTRS)

    Hsui, Albert T.; Tang, Xiao-Ming; Toksoz, M. Nafi

    1990-01-01

    A new approximate analytic model is developed for the thermal structure of a subducting plate with a finite length. This model provides the capability of easily examining the thermal and mechanical structure of a subducting plate with different lengths and at different angles. Also, the torque balance of a descending plate can be examined, and effects such as the leading edge effect, the adiabatic compression effect, and the phase change effect can be incorporated. A comparison with observed data indicates that short slabs are likely under torque equilibrium at present, while long slabs are probably dominated by their gravitational torques such that their dip angles are transient, moving toward a steeper dip angle similar to that of the Mariana slab.

  13. Drag Measurements of Porous Plate Acoustic Liners

    NASA Technical Reports Server (NTRS)

    Wolter, John D.

    2005-01-01

    This paper presents the results of direct drag measurements on a variety of porous plate acoustic liners. The existing literature describes numerous studies of drag on porous walls with injection or suction, but relatively few of drag on porous plates with neither injection nor suction. Furthermore, the porosity of the porous plate in existing studies is much lower than typically used in acoustic liners. In the present work, the acoustic liners consisted of a perforated face sheet covering a bulk acoustic absorber material. Factors that were varied in the experiment were hole diameter, hole pattern, face sheet thickness, bulk material type, and size of the gap (if any) between the face sheet and the absorber material.

  14. Aerodynamic drag reduction by vertical splitter plates

    NASA Astrophysics Data System (ADS)

    Gilliéron, Patrick; Kourta, Azeddine

    2010-01-01

    The capacity of vertical splitter plates placed at the front or the rear of a simplified car geometry to reduce drag, with and without skew angle, is investigated for Reynolds numbers between 1.0 × 106 and 1.6 × 106. The geometry used is a simplified geometry to represent estate-type vehicles, for the rear section, and MPV-type vehicle. Drag reductions of nearly 28% were obtained for a zero skew angle with splitter plates placed at the front of models of MPV or utility vehicles. The results demonstrate the advantage of adapting the position and orientation of the splitter plates in the presence of a lateral wind. All these results confirm the advantage of this type of solution, and suggest that this expertise should be used in the automotive field to reduce consumption and improve dynamic stability of road vehicles.

  15. Hydrogen Embrittlement of Pulse-Plated Nickel

    NASA Astrophysics Data System (ADS)

    Reese, Eggert D.; Von Bestenbostel, Wolfgang; Sebald, Torsten; Paronis, Georgios; Vanelli, Diego; Müller, Yves

    2014-08-01

    The objective of the European-funded project MultiHy (Multiscale modeling of hydrogen embrittlement in crystalline materials) is the development of multiscale models for hydrogen transport in complex microstructures. The validation and application of the models will be carried out by investigating the role of the microstructure in industrial problems involving hydrogen embrittlement (HE) of advanced materials. Pulse-plated nickel (PP-Ni) material, as used in various industrial applications, has shown a susceptibility to HE that may cause premature failure of a structure. Due to the nature of the pulse-plating process, H is incorporated into the microstructure of the material. This H may lead to crack initiation when combined with localized stress concentrations due to subsequent manufacturing steps, e.g., welding. This article provides an overview of experimental studies aimed at evaluating the influence of the microstructure on the susceptibility of PP-Ni to HE and, ultimately, at improving the plating process.

  16. Impact resistance of composite laminated sandwich plates

    NASA Astrophysics Data System (ADS)

    Kim, Chun-Gon; Jun, Eui-Jin

    1992-01-01

    Investigated are the effects of face layup sequence and core density of a sandwich plate on the impact delamination area of the laminated facesheet. The sandwich plate is made of graphite/epoxy faces and Nomex honeycomb core. The size and shape of delamination due to impact at each interply location have been measured by the room temperature deply technique. The shape of the interply delamination under impact is, in general, found to be two-lobed. The shape exhibits very peculiar regularity under various experimental conditions. The quantitative measurement of delamination size has shown that the face layup with small relative orientation between adjacent plies and high density core are desirable in sandwich plates to reduce the impact delamination.

  17. Deformation and instability of underthrusting lithospheric plates

    NASA Technical Reports Server (NTRS)

    Liu, H.

    1972-01-01

    Models of the underthrusting lithosphere are constructed for the calculation of displacement and deflection. First, a mathematical theory is developed that rigorously demonstrates the elastic instability in the decending lithosphere. The theory states that lithospheric thrust beneath island arcs becomes unstable and suffers deflection as the compression increases. Thus, in the neighborhood of the edges where the lithospheric plate plunges into the asthenosphere and mesosphere its shape will be contorted. Next, the lateral displacement is calculated, and it is shown that, before contortion, the plate will thicken and contract at different positions with the variation in thickness following a parabolic profile. Finally, the depth distribution of the intermediate and deep focus earthquakes is explained in terms of plate buckling and contortion.

  18. Plate tectonics drive tropical reef biodiversity dynamics

    NASA Astrophysics Data System (ADS)

    Leprieur, Fabien; Descombes, Patrice; Gaboriau, Théo; Cowman, Peter F.; Parravicini, Valeriano; Kulbicki, Michel; Melián, Carlos J.; de Santana, Charles N.; Heine, Christian; Mouillot, David; Bellwood, David R.; Pellissier, Loïc

    2016-05-01

    The Cretaceous breakup of Gondwana strongly modified the global distribution of shallow tropical seas reshaping the geographic configuration of marine basins. However, the links between tropical reef availability, plate tectonic processes and marine biodiversity distribution patterns are still unknown. Here, we show that a spatial diversification model constrained by absolute plate motions for the past 140 million years predicts the emergence and movement of diversity hotspots on tropical reefs. The spatial dynamics of tropical reefs explains marine fauna diversification in the Tethyan Ocean during the Cretaceous and early Cenozoic, and identifies an eastward movement of ancestral marine lineages towards the Indo-Australian Archipelago in the Miocene. A mechanistic model based only on habitat-driven diversification and dispersal yields realistic predictions of current biodiversity patterns for both corals and fishes. As in terrestrial systems, we demonstrate that plate tectonics played a major role in driving tropical marine shallow reef biodiversity dynamics.

  19. Noncyanide cadmium plating baths. Final report

    SciTech Connect

    Pearlstein, F.; Agarwala, V.S.

    1991-10-04

    One approach to minimizing toxic wastes is to eliminate the use of cyanide plating baths. Non-cyanide zinc plating baths have been successfully developed and have found widespread use. An investigation was conducted in an attempt to accomplish similar results with cadmium plating baths. The focus of this study was on additives to a near neutral cadmium bath, free of complexing agents. A Hull cell was used to enable visualization of deposits over a broad range of cathode current densities. Experimental design (Taguchi Method) was used to optimize bath parameters and constituent concentrations. Bath parameters have been developed which indicate promise for producing dense deposits with good covering power, and relatively low tendency for hydrogen embrittlement.

  20. Retardation Measurements of Infrared PVA Wave plate

    NASA Astrophysics Data System (ADS)

    Sun, Y.; Z, H.; W, D.; D, Y.; Z, Z.; S, J.

    The wave plate made of Polyvinyl Alcohol PVA plastic film has several advantages such as its lower cost and insensitivity to temperature and incidence angle so it has been used in the Solar Multi-Channel Telescope SMCT in China But the important parameter retardations of PVA wave plates in the near infrared wavelength have never been provided In this paper a convenient and high precise instrument to get the retardations of discrete wavelengths or a continuous function of wavelength in near infrared is developed In this method the retardations of wave plates have been determined through calculating the maximum and minimum of light intensity The instrument error has been shown Additionally we can get the continuous direction of wavelength retardations in the ultraviolet visible or infrared spectral in another way

  1. Plate motions: Simpler than they look

    NASA Astrophysics Data System (ADS)

    Sambridge, M.; Iaffaldano, G.; Bodin, T.

    2012-12-01

    Plate motions shape Earth's surface through time. These kinematics are of paramount importance to make inferences on sea-level change, mantle/lithosphere interactions and dynamic topography among others. Over the last few decades much effort has gone into plate motion reconstructions at finer temporal resolution from ocean-floor finite-rotations. However, measurements feature substantial noise arising mainly from the challenge of identifying precisely magnetic lineations of the ocean-floor, as well as from uncertainties in geomagnetic reversal timescales. It is therefore standard practise to smooth reconstructions typically by averaging over 2 to 5 Myr-long intervals. But this comes at the price of i) downgrading the native resolution of costly measurements and ii) having to choose one among many smoothing methods that do not yield a unique result. At the native resolution of reconstructions, however, the scenario arising is puzzling, as plate motions vary erratically and significantly over short periods of less than 1 Myr. This equally undermines our ability to make geodynamic inferences, because the rates at which forces need to be built upon plates to explain these kinematics far exceed the most optimistic estimates based, for instance, on the temporal evolution of lithospheric slabs into Earth's mantle. Here we focus on the longest and most temporally-resolved records of ocean-floor spreading ever produced, across mid-oceanic ridges in the Atlantic, Indian and South Pacific Oceans. We show that the largest kinematic changes across these ridges relate to data-noise, and are of apparent nature. We overcome this limitation employing a trans-dimensional hierarchical Bayesian framework, which drastically reduces noise without loss of temporal resolution. Changes in the temporal trends of plate motions occur on timescales no shorter than a few million years, yielding simpler kinematic patterns and more plausible dynamics. This has important implications for the

  2. Tomography, the geoid and plate motions

    SciTech Connect

    Gable, C.W.; O'connell, R.J. )

    1991-01-01

    The dynamics of the earth's mantle and its relationship to mantle structure as revealed by seismic tomography, the geoid, and plate motions are discussed in a critical review of U.S. research from the period 1987-1990. Sections are devoted to plates and mantle convection; seismic anomalies, flow, and the geoid; subducted slabs and the 670-km discontinuity; the physical properties of the mantle; plumes; and computational and experimental modeling efforts. Also included is a comprehensive bibliography for the period. 248 refs.

  3. Seismology: tectonic strain in plate interiors?

    PubMed

    Calais, E; Mattioli, G; DeMets, C; Nocquet, J-M; Stein, S; Newman, A; Rydelek, P

    2005-12-15

    It is not fully understood how or why the inner areas of tectonic plates deform, leading to large, although infrequent, earthquakes. Smalley et al. offer a potential breakthrough by suggesting that surface deformation in the central United States accumulates at rates comparable to those across plate boundaries. However, we find no statistically significant deformation in three independent analyses of the data set used by Smalley et al., and conclude therefore that only the upper bounds of magnitude and repeat time for large earthquakes can be inferred at present. PMID:16355163

  4. Relationship between plume and plate tectonics

    NASA Astrophysics Data System (ADS)

    Puchkov, V. N.

    2016-07-01

    The relationship between plate- and plume-tectonics is considered in view of the growth and breakdown of supercontinents, active rifting, the formation of passive volcanic-type continental margins, and the origin of time-progressive volcanic chains on oceanic and continental plates. The mantle wind phenomenon is described, as well as its effect on plume morphology and anisotropy of the ambient mantle. The interaction of plumes and mid-ocean ridges is discussed. The principles and problems of plume activity analysis in subduction- and collision-related foldbelts are considered and illustrated with examples.

  5. Imaging plates calibration to X-rays

    NASA Astrophysics Data System (ADS)

    Curcio, A.; Andreoli, P.; Cipriani, M.; Claps, G.; Consoli, F.; Cristofari, G.; De Angelis, R.; Giulietti, D.; Ingenito, F.; Pacella, D.

    2016-05-01

    The growing interest for the Imaging Plates, due to their high sensitivity range and versatility, has induced, in the last years, to detailed characterizations of their response function in different energy ranges and kind of radiation/particles. A calibration of the Imaging Plates BAS-MS, BAS-SR, BAS-TR has been performed at the ENEA-Frascati labs by exploiting the X-ray fluorescence of different targets (Ca, Cu, Pb, Mo, I, Ta) and the radioactivity of a BaCs source, in order to cover the X-ray range between few keV to 80 keV.

  6. Cascade impactor and jet plate for same

    DOEpatents

    Dahlin, Robert S.; Farthing, William E.; Landham Jr., Edward C.

    2004-02-03

    A sampling system and method for sampling particulate matter from a high-temperature, high-pressure gas stream. A cyclone sampler for use at high temperatures and pressures, and having threadless sacrificial connectors is disclosed. Also disclosed is an improved cascade impactor including jet plates with integral spacers, and alignment features provided for aligning the jet plates with their associated collection substrates. An activated bauxite alkali collector is disclosed, and includes an alumina liner. The sampling system can be operated remotely or locally, and can be permanently installed or configured as a portable system.

  7. Ponderomotive phase plate for transmission electron microscopes

    DOEpatents

    Reed, Bryan W.

    2012-07-10

    A ponderomotive phase plate system and method for controllably producing highly tunable phase contrast transfer functions in a transmission electron microscope (TEM) for high resolution and biological phase contrast imaging. The system and method includes a laser source and a beam transport system to produce a focused laser crossover as a phase plate, so that a ponderomotive potential of the focused laser crossover produces a scattering-angle-dependent phase shift in the electrons of the post-sample electron beam corresponding to a desired phase contrast transfer function.

  8. PC-based car license plate reader

    NASA Astrophysics Data System (ADS)

    Hwang, Chung-Mu; Shu, Shyh-Yeong; Chen, Wen-Yu; Chen, Yie-Wern; Wen, Kuang-Pu

    1992-11-01

    A car license plate reader (CLPR) using fuzzy inference and neural network algorithm has been developed in Industrial Technology Research Institute (ITRI) and installed in highway toll stations to identify stolen cars. It takes an average of 0.7 seconds to recognize a car license plate by using a PC with 80486-50 CPU. The recognition rate of the system is about 97%. The techniques of CLPR include vehicle sensing, image grab control, optic pre- processing, lighting, and optic character recognition (OCR). The CLPR can be used in vehicle flow statistics, the checking of stolen vehicles, automatic charging systems in parking lots or garage management, and so on.

  9. Spirit Beside 'Home Plate,' Sol 1809

    NASA Technical Reports Server (NTRS)

    2009-01-01

    NASA Mars Exploration Rover Spirit used its navigation camera to take the images assembled into this 120-degree view southward after a short drive during the 1,809th Martian day, or sol, of Spirit's mission on the surface of Mars (February 3, 2009).

    Spirit had driven about 2.6 meters (8.5 feet) that sol, continuing a clockwise route around a low plateau called 'Home Plate.' In this image, the rocks visible above the rovers' solar panels are on the slope at the northern edge of Home Plate.

    This view is presented as a cylindrical projection with geometric seam correction.

  10. Plating of open pediatric tibia fractures.

    PubMed

    Head, James; Lewis, T R; Puffinbarger, William; Garbrecht, Erika

    2014-07-01

    This study is a single center retrospective chart and radiographic review of patients with open tibia fractures under the age of 16 years of age over past 10 years. The purpose of this study is to investigate the treatment of open pediatric tibia fractures with plating in regards to time to ambulation, time to union, and deformity in comparison to other treatment options. We found that plating open pediatric tibia fractures is a safe treatment option that can lead to excellent results with low risk of complications. PMID:25223152

  11. Ion sputter textured graphite electrode plates

    NASA Technical Reports Server (NTRS)

    Curren, A. N.; Forman, R.; Sovey, J. S.; Wintucky, E. G. (Inventor)

    1983-01-01

    A specially textured surface of pyrolytic graphite exhibits extremely low yields of secondary electrons and reduced numbers of reflected primary electrons after impingement of high energy primary electrons. Electrode plates of this material are used in multistage depressed collectors. An ion flux having an energy between 500 iV and 1000 iV and a current density between 1.0 mA/sq cm and 6.0 mA/sq cm produces surface roughening or texturing which is in the form of needles or spires. Such textured surfaces are especially useful as anode collector plates in high tube devices.

  12. Using plate mapping to examine sensitivity to plate size in food portions and meal composition among college students

    PubMed Central

    Sharp, David E.; Sobal, Jeffery

    2015-01-01

    People eat meals rather than nutrients or food groups. Plate size may influence meal size, meal composition, and food type. To examine effects of plate size on meals, we developed a method we label plate mapping. A quasi-experimental study asked university students to accurately draw what they would like to eat for dinner on either a 9″ or 11″ paper plate. Coding plate drawings for total meal size revealed that students drew an average of 26% more food on larger plates. When plates were coded for meal composition we found that the biggest three food portions drawn by students were bigger on 11″ plates, with 70% of the overall difference in food area occurring in the biggest food. Participants drew bigger portions of vegetables on larger plates, while other food types showed little change in mean size. Gender moderated plate sensitivity for food types: women drew 36% bigger vegetable portions than men on larger plates. Smaller plates may lead to smaller meal sizes, but plate size may differentially influence composition of meals for men and women. These findings suggest plate mapping can be used to reflect meal conceptualizations and assess sensitivity to plate size. PMID:22867909

  13. No-net-rotation model of current plate velocities incorporating plate motion model NUVEL-1

    NASA Technical Reports Server (NTRS)

    Argus, Donald F.; Gordon, Richard G.

    1991-01-01

    NNR-NUVEL1 is presented which is a model of plate velocities relative to the unique reference frame defined by requiring no-net-rotation of the lithosphere while constraining relative plate velocities to equal those in global plate motion model NUVEL-1 (DeMets et al., 1990). In NNR-NUVEL1, the Pacific plate rotates in a right-handed sense relative to the no-net-rotation reference frame at 0.67 deg/m.y. about 63 deg S, 107 deg E. At Hawaii the Pacific plate moves relative to the no-net-rotation reference frame at 70 mm/yr, which is 25 mm/yr slower than the Pacific plate moves relative to the hotspots. Differences between NNR-NUVEL1 and HS2-NUVEL1 are described. The no-net-rotation reference frame differs significantly from the hotspot reference frame. If the difference between reference frames is caused by motion of the hotspots relative to a mean-mantle reference frame, then hotspots beneath the Pacific plate move with coherent motion towards the east-southeast. Alternatively, the difference between reference frames can show that the uniform drag, no-net-torque reference frame, which is kinematically equivalent to the no-net-rotation reference frame, is based on a dynamically incorrect premise.

  14. Operative Treatment of Clavicle Midshaft Fractures: Comparison between Reconstruction Plate and Reconstruction Locking Compression Plate

    PubMed Central

    Song, Kwang-Soon; Min, Byung-Woo; Bae, Ki-Cheor; Lee, Kyung-Jae

    2010-01-01

    Background To compare the outcomes of reconstruction plate and reconstruction locking compression plate (LCP) for the treatment of clavicle midshaft fractures. Methods Forty one patients with a clavicle midshaft fracture were treated by internal fixation with a reconstruction plate (19 patients) or reconstruction LCP (22 patients). The clinical and radiological results were evaluated according to the Quick Disability of the Arm, Shoulder, and Hand (DASH) score and plain radiographs. Results The mean time to union was 14.6 weeks in the reconstruction plate group compared to 13.2 weeks in the reconstruction LCP group (p > 0.05). The mean score to Quick DASH was 33.85 points in the reconstruction plate group compared to 34.81 points in the reconstruction LCP group (p > 0.05). The complications in the reconstruction plate were hypertrophic scarring in 2 cases, painful shoulder in 2 cases, limitation of shoulder motion in 2 cases, and screw loosening in 3 cases. In addition, the complications in the reconstruction LCP group was hypertrophic scarring in 4 cases, painful shoulder in 1 case and a limitation of shoulder motion in 1case (p > 0.05). Conclusions This study showed radiologically and clinically satisfactory results in both groups. Overall, operative treatment with a Reconstruction plate or reconstruction LCP for clavicle shaft fractures can be used to obtain stable fixation. PMID:20808586

  15. Are Hook Plates Advantageous Compared to Antiglide Plates for Vertical Shear Malleolar Fractures?

    PubMed

    Jones, Daniel A; Cannada, Lisa K; Bledsoe, J Gary

    2016-01-01

    This study was designed to evaluate the biomechanical properties of a hook plate (HP) vs an antiglide (AG) plate for supination-adduction (SAD)-ankle fractures. Identical polyurethane tibial models were obtained and vertical fractures were created. The fractures were stabilized with 1 of the following: one-third tubular plate in an AG fashion with 2 screws proximal to the fracture; an AG plate with an additional screw perpendicular to the vertical shear fragment (MAG), or an HP. Ten models were randomly assigned to each of the 3 groups. The constructs were tested in offset-axial loading and were evaluated for construct stiffness and load-to-failure. The MAG construct yielded better stiffness compared with the AG plate (P < .05) and the HP (P < .05). The plate stiffness of the HP construct compared with the AG was not significant (P = .350). In regards to load-to-failure, the difference between MAG and AG was 638 N, and MAG and HP was 530 N (both P < .05). The HP had a load-to-failure that was, on average, 108 N more than the AG but was not significant (P = .063). A one-third tubular plate in the MAG fashion provided a stable, strong construct for fixation of vertical shear medial malleolus fractures. PMID:26991590

  16. The nature and location of the plate boundary between the Anatolian and African plates

    NASA Astrophysics Data System (ADS)

    deǧer Özbakır, Ali; Wortel, Rinus; Govers, Rob

    2010-05-01

    Overall convergence of the African, Arabian and Eurasian plates, and the westward escape of Anatolia has resulted in an evolving plate boundary zone since the Miocene. In the Eastern Mediterranean, the current location and nature of the plate boundary between the Anatolian and the African plates is difficult to trace due to the scattered crustal earthquakes, and the absence of deeper earthquakes. In this study we aim to better constrain the nature and the location of the plate boundary. GPS-derived velocity field and stresses from earthquake mechanism solutions comprise the datasets which short time scale (elastic) models can be compared to. We model the stresses and deformation on the overriding plate by incorporating convergence of Africa and Arabia towards stable Eurasia, and rollback of the Hellenic trench. Investigation of the plate boundary consists of constraining the directions of motions over the segments which make up the boundary. We assume various types and locations for the plate boundary within the observational limits. We use a spherical plane stress finite element model to test these possibilities. We find that stresses and displacements are sensitive to both the location and the nature of the plate boundary. We obtain the minimum misfit with the data in a model where we assume the following: (1) the segment between Hellenic and the Cyprus arcs have both down-dip and fault parallel motions, (2) the connection between the Cyprus arc and Arabia--Eurasia collision zone is pure strike-slip. In all our models, an extra pull force on Anatolia is required to explain the high velocities in southwest Anatolia. This force may be related to return flow around the lateral edge of the Aegean slab.

  17. Actively controlling coolant-cooled cold plate configuration

    DOEpatents

    Chainer, Timothy J.; Parida, Pritish R.

    2016-04-26

    Cooling apparatuses are provided to facilitate active control of thermal and fluid dynamic performance of a coolant-cooled cold plate. The cooling apparatus includes the cold plate and a controller. The cold plate couples to one or more electronic components to be cooled, and includes an adjustable physical configuration. The controller dynamically varies the adjustable physical configuration of the cold plate based on a monitored variable associated with the cold plate or the electronic component(s) being cooled by the cold plate. By dynamically varying the physical configuration, the thermal and fluid dynamic performance of the cold plate are adjusted to, for example, optimally cool the electronic component(s), and at the same time, reduce cooling power consumption used in cooling the electronic component(s). The physical configuration can be adjusted by providing one or more adjustable plates within the cold plate, the positioning of which may be adjusted based on the monitored variable.

  18. Plate-induced Miocene extension in southern California

    SciTech Connect

    Stuart, W.D. Univ. of California, Santa Barbara, CA )

    1992-01-01

    Miocene crustal extension in southern California can be explained by the interaction of tectonic plates in relative motion. The Pacific, Juan de Fuca, and Farallon (Guadalupe) plates are represented by flat elastic plates surrounded by an infinite elastic plate, the eastern part of which represents the North America plate. Forcing is by assigned subduction pull, and tractions at all plate boundaries satisfy a viscous constitutive law. Plate bottoms are stress-free. In the first part of the solution plate velocities and boundary tractions are found from static equilibrium. Then principal horizontal stresses and strains in plate interiors caused by tractions and subduction pull are found by a boundary element procedure. Using plate boundary geometry from Stock and Hodges for early- and mid-Miocene times, it is found that the portion of the North America plate margin between the Mendocino and Rivera triple junctions has maximum extensional strain directed westward. This result is generally consistent with directions associated with metamorphic core complex formation in southern California. The model is also consistent with extensional strain and rotation sense of crustal blocks in the vicinity of Los Angeles, as inferred by Luyendyk and others from paleomagnetic data. In the model the greatest extensional strain of the North America plate occurs near the Pacific-North America transform, in the area above the absent Farallon slab. Extension direction varies from northwest to southwest according to plate geometry, subduction pull (Juan de Fuca and Guadalupe), and plate boundary tractions.

  19. Treatment of middle-third clavicle fractures using anterior plating with a dynamic compression plate (DCP).

    PubMed

    Subramanian, Padmanabhan; Joshi, Meera; Shilston, Sophie; Wallace, Donald; Pearce, Oliver J

    2013-03-01

    Significantly displaced midshaft clavicle fractures can be managed operatively to restore anatomy and allow early mobilization. Several techniques have described using precontoured anatomically designed plates placed on the superior surface of the bone or reconstruction plates contoured by the surgeon placed either superiorly or anteriorly. We describe the use of the dynamic compression plate placed anteriorly on the clavicle in treating these fractures and discuss the relative advantages of this technique. We have a case series of 8 patients over a 2-year period, who were followed up and all went on to successful fracture union. PMID:23423233

  20. Copper plating on the polyimide film by electroless plating techniques for EMI shielding.

    PubMed

    Ji, Eun Sun; Cha, Hyun Gil; Kim, Chang Woo; Kang, Dong In; Kang, Young Soo

    2009-12-01

    In this work, the metal plated film was prepared by electroless plating techniques. The film was prepared for the fabrication of EMI shielding. Polyimide film was treated by base solution for etching and then activated by silver. The modified polyimide film was immersed into the electroless copper plating solution which has different molar ratios of nickel in the solution. The thickness and surface morphology of copper layer on the polyimide films were characterized with scanning electron microscopy (SEM). Furthermore, EMI shielding ability of the film was calculated by measuring reflectivity of EM wave on the film surface using the equation of Schelkunoff theory. PMID:19908729

  1. Elastocapillary coalescence of plates and pillars

    PubMed Central

    Wei, Z.; Schneider, T. M.; Kim, J.; Kim, H.-Y.; Aizenberg, J.; Mahadevan, L.

    2015-01-01

    When a fluid-immersed array of supported plates or pillars is dried, evaporation leads to the formation of menisci on the tips of the plates or pillars that bring them together to form complex patterns. Building on prior experimental observations, we use a combination of theory and computation to understand the nature of this instability and its evolution in both the two- and three-dimensional setting of the problem. For the case of plates, we explicitly derive the interaction torques based on the relevant physical parameters associated with pillar deformation, contact-line pinning/depinning and fluid volume changes. A Bloch-wave analysis for our periodic mechanical system captures the window of volumes where the two-plate eigenvalue characterizes the onset of the coalescence instability. We then study the evolution of these binary clusters and their eventual elastic arrest using numerical simulations that account for evaporative dynamics coupled to capillary coalescence. This explains both the formation of hierarchical clusters and the sensitive dependence of the final structures on initial perturbations, as seen in our experiments. We then generalize our analysis to treat the problem of pillar collapse in three dimensions, where the fluid domain is completely connected and the interface is a minimal surface with the uniform mean curvature. Our theory and simulations capture the salient features of experimental observations in a range of different situations and may thus be useful in controlling the ensuing patterns. PMID:25792949

  2. The dynamic inelastic response of delaminated plates

    SciTech Connect

    Addessio, F.L.; Williams, T.O.

    1996-12-01

    A generalized theory for laminated plates with delaminations is used to consider the influence of inelastic deformations on the dynamic behavior of composite plates with delaminations. The laminate model is based on a generalized displacement formulation implemented at the layer level. The delamination behavior can be modeled using any general interfacial fracture law: however, for the current work a linear model is employed. The interfacial displacement jumps are expressed in an internally consistent fashion in terms of the fundamental unknown interfacial tractions. The current theory imposes no restrictions on the size, location, distribution, or direction of growth of the delaminations. The proposed theory is used to consider the inelastic, dynamic response of delaminated plates in cylindrical bending subjected to a ramp and hold type of loading. The individual layers in the current study are assumed to be either titanium or aluminum. The inelastic response of both materials is modeled using the unified viscoplastic theory of Bodner and Partom. It is shown that the presence of both inelastic behavior and delamination can have a significant influence on the plate response. In particular it is shown that these mechanisms are strongly interactive. This result emphasizes the need to consider both mechanisms simultaneously.

  3. 30 CFR 33.11 - Approval plates.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Approval plates. 33.11 Section 33.11 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR TESTING, EVALUATION, AND APPROVAL OF MINING PRODUCTS DUST COLLECTORS FOR USE IN CONNECTION WITH ROCK DRILLING IN COAL MINES General...

  4. 30 CFR 33.11 - Approval plates.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Approval plates. 33.11 Section 33.11 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR TESTING, EVALUATION, AND APPROVAL OF MINING PRODUCTS DUST COLLECTORS FOR USE IN CONNECTION WITH ROCK DRILLING IN COAL MINES General...

  5. Wave interaction with dual circular porous plates

    NASA Astrophysics Data System (ADS)

    Mondal, Arpita; Gayen, R.

    2015-12-01

    In this paper we investigated the reflection and the transmission of a system of two symmetric circular-arc-shaped thin porous plates submerged in deep water within the context of linear theory. The hypersingular integral equation technique has been used to analyze the problem mathematically. The integral equations are formulated by applying Green's integral theorem to the fundamental potential function and the scattered potential function into a suitable fluid region, and then using the boundary condition on the porous plate surface. These are solved approximately using an expansion-cum-collocation method using the behaviour of the potential functions at the tips of the plates. This method ultimately produces a very good numerical approximation for the reflection and the transmission coefficients and hydrodynamic force components. The numerical results are depicted graphically against the wave number for a variety of layouts of the arc. Some results are compared with known results for similar configurations of dual rigid plate systems available in the literature with good agreement.

  6. A swirl flow evaporative cold plate

    NASA Technical Reports Server (NTRS)

    Niggemann, R. E.; Greenlee, W. J.; Hill, D. G.; Ellis, W.; Marshall, P.

    1985-01-01

    A forced flow evaporative cold plate is under development for future application to the thermal bus concept being pursued by NASA for Space Station Thermal Control. The vaporizer is a swirl-flow device employing a spiral tube coil geometry sandwiched between conductive metal plates upon which electric components could be mounted. This concept is based on the inherent phase separation that occurs in a two phase stream in curvilinear flow. This is a zero 'g' design with one 'g' all-attitude capability and is capable of high heat transfer coefficients, good isothermality, and the ability to function at heat fluxes approaching 5w/sq cm on the cold plates (10w/sq cm on the tube wall) with Freon 114. The advantages of this design over other two phase evaporator approaches are high heat flux capability, simplified control requirements, insensitivity to micro-gravity oscillations, and inexpensive manufacturability. The program included design, fabrication, and test of such a cold plate utilizing an existing test stand developed for two-phase thermal management system (TPTMS) testing. Test results analysis and conclusions are included.

  7. 30 CFR 18.11 - Approval plate.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... MINING PRODUCTS ELECTRIC MOTOR-DRIVEN MINE EQUIPMENT AND ACCESSORIES General Provisions § 18.11 Approval... the applicant, and spaces for the approval number, serial number, and the type or model of machine. (2... equipment. (c) The approval plate identifies as permissible the machine or accessory to which it is...

  8. 30 CFR 18.11 - Approval plate.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... MINING PRODUCTS ELECTRIC MOTOR-DRIVEN MINE EQUIPMENT AND ACCESSORIES General Provisions § 18.11 Approval... the applicant, and spaces for the approval number, serial number, and the type or model of machine. (2... equipment. (c) The approval plate identifies as permissible the machine or accessory to which it is...

  9. 30 CFR 18.11 - Approval plate.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... MINING PRODUCTS ELECTRIC MOTOR-DRIVEN MINE EQUIPMENT AND ACCESSORIES General Provisions § 18.11 Approval... the applicant, and spaces for the approval number, serial number, and the type or model of machine. (2... equipment. (c) The approval plate identifies as permissible the machine or accessory to which it is...

  10. 30 CFR 18.11 - Approval plate.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... MINING PRODUCTS ELECTRIC MOTOR-DRIVEN MINE EQUIPMENT AND ACCESSORIES General Provisions § 18.11 Approval... the applicant, and spaces for the approval number, serial number, and the type or model of machine. (2... equipment. (c) The approval plate identifies as permissible the machine or accessory to which it is...

  11. Spectral characterization of storage phosphor imaging plates

    SciTech Connect

    Deresch, A.; Jechow, M.; Gollwitzer, C.

    2014-02-18

    This work presents attenuation and sensitivity measurements of radiographic imaging plates (IPs) with quasimonoenergetic X-rays in the 8–60 kiloelectronvolt range. The measurements are used to validate theoretical predictions. A short overview of the theoretical model is given. The model can be used to describe the sensitivity of different detector types to a wide range of X-ray energies.

  12. Quantitative tests for plate tectonics on Venus

    NASA Technical Reports Server (NTRS)

    Kaula, W. M.; Phillips, R. J.

    1981-01-01

    Quantitative comparisons are made between the characteristics of plate tectonics on the earth and those which are possible on Venus. Considerations of the factors influencing rise height and relating the decrease in rise height to plate velocity indicate that the rate of topographic dropoff from spreading centers should be about half that on earth due to greater rock-fluid density contrast and lower temperature differential between the surface and interior. Statistical analyses of Pioneer Venus radar altimetry data and global earth elevation data is used to identify 21,000 km of ridge on Venus and 33,000 km on earth, and reveal Venus ridges to have a less well-defined mode in crest heights and a greater concavity than earth ridges. Comparison of the Venus results with the spreading rates and associated heat flow on earth reveals plate creation rates on Venus to be 0.7 sq km/year or less and indicates that not more than 15% of Venus's energy is delivered to the surface by plate tectonics, in contrast to values of 2.9 sq km a year and 70% for earth.

  13. Spreading continents kick-started plate tectonics.

    PubMed

    Rey, Patrice F; Coltice, Nicolas; Flament, Nicolas

    2014-09-18

    Stresses acting on cold, thick and negatively buoyant oceanic lithosphere are thought to be crucial to the initiation of subduction and the operation of plate tectonics, which characterizes the present-day geodynamics of the Earth. Because the Earth's interior was hotter in the Archaean eon, the oceanic crust may have been thicker, thereby making the oceanic lithosphere more buoyant than at present, and whether subduction and plate tectonics occurred during this time is ambiguous, both in the geological record and in geodynamic models. Here we show that because the oceanic crust was thick and buoyant, early continents may have produced intra-lithospheric gravitational stresses large enough to drive their gravitational spreading, to initiate subduction at their margins and to trigger episodes of subduction. Our model predicts the co-occurrence of deep to progressively shallower mafic volcanics and arc magmatism within continents in a self-consistent geodynamic framework, explaining the enigmatic multimodal volcanism and tectonic record of Archaean cratons. Moreover, our model predicts a petrological stratification and tectonic structure of the sub-continental lithospheric mantle, two predictions that are consistent with xenolith and seismic studies, respectively, and consistent with the existence of a mid-lithospheric seismic discontinuity. The slow gravitational collapse of early continents could have kick-started transient episodes of plate tectonics until, as the Earth's interior cooled and oceanic lithosphere became heavier, plate tectonics became self-sustaining. PMID:25230662

  14. Plate Tectonics and Continental Drift: Classroom Ideas.

    ERIC Educational Resources Information Center

    Stout, Prentice K.

    1983-01-01

    Suggests various classroom studies related to plate tectonics and continental drift, including comments on and sources of resource materials useful in teaching the topics. A complete list of magazine articles on the topics from the Sawyer Marine Resource Collection may be obtained by contacting the author. (JN)

  15. Plate tectonics: Delayed response to mantle pull

    NASA Astrophysics Data System (ADS)

    Nedimović, Mladen R.

    2016-08-01

    At mid-ocean ridges, the directions in which plates spread and the underlying mantle flows were thought to broadly align. A synthesis of results from ridges that spread at a variety of rates reveals that instead there may be a systematic skew.

  16. EVAPORATIVE RECOVERY OF CHROMIUM PLATING RINSE WATERS

    EPA Science Inventory

    This demonstration project documents the practicality of a new evaporative approach for recovering chromic acid from metal finishing rinse waste waters, as well as the economics of the system under actual operating conditions. The six-month study of chrome plating operations was ...

  17. Brazed bipolar plates for PEM fuel cells

    DOEpatents

    Neutzler, Jay Kevin

    1998-01-01

    A liquid-cooled, bipolar plate separating adjacent cells of a PEM fuel cell comprising corrosion-resistant metal sheets brazed together so as to provide a passage between the sheets through which a dielectric coolant flows. The brazement comprises a metal which is substantially insoluble in the coolant.

  18. Brazed bipolar plates for PEM fuel cells

    DOEpatents

    Neutzler, J.K.

    1998-07-07

    A liquid-cooled, bipolar plate separating adjacent cells of a PEM fuel cell comprises corrosion-resistant metal sheets brazed together so as to provide a passage between the sheets through which a dielectric coolant flows. The brazement comprises a metal which is substantially insoluble in the coolant. 6 figs.

  19. Copyboard Quickly Makes Clean Printing Plates

    NASA Technical Reports Server (NTRS)

    Balandis, W. D.

    1985-01-01

    Vacuum-chuck eliminates glass and sponge artwork support. Vacuum copyboard allows camera-ready original slid on top plate for proper positioning, then holds securely for photography. Bleed valve allows vacuum in copyboard box adjusted for small or large originals. With new copyboard, time-consuming and costly procedures unnecessary.

  20. 30 CFR 18.13 - Certification plate.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... component in a manner acceptable to MSHA. The method of attachment shall not impair any explosion-proof characteristics of the component. The plate shall be of serviceable material, acceptable, to MSHA, and shall contain the following: Certified as complying with the applicable requirements of 30 CFR...

  1. 19 CFR 115.32 - Approval plates.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 19 Customs Duties 1 2012-04-01 2012-04-01 false Approval plates. 115.32 Section 115.32 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY CARGO CONTAINER AND ROAD VEHICLE CERTIFICATION PURSUANT TO INTERNATIONAL CUSTOMS CONVENTIONS Procedures for Approval of Containers by Design Type...

  2. 19 CFR 115.42 - Approval plates.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 19 Customs Duties 1 2012-04-01 2012-04-01 false Approval plates. 115.42 Section 115.42 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY CARGO CONTAINER AND ROAD VEHICLE CERTIFICATION PURSUANT TO INTERNATIONAL CUSTOMS CONVENTIONS Procedures for Approval of Containers After Manufacture...

  3. Ion plating technique improves thin film deposition

    NASA Technical Reports Server (NTRS)

    Mattox, D. M.

    1968-01-01

    Ion plating technique keeps the substrate surface clean until the film is deposited, allows extensive diffusion and chemical reaction, and joins insoluble or incompatible materials. The technique involves the deposition of ions on the substrate surface while it is being bombarded with inert gas ions.

  4. Plate evolution and petroliferous basins of China

    SciTech Connect

    Wu Shou Cheng; Zhang Wen Zhao

    1989-03-01

    The writers have compiled a group of paleogeographic and paleostructural maps of tectonic plates and sedimentary basins of China based on paleomagnetic, paleoclimatic, and paleoecologic data. The paleoenvironments and regional conditions that instigated the origin of petroleum in the superbasins have been reconstructed.

  5. Digitization of Archives of Astronomical Plates

    NASA Astrophysics Data System (ADS)

    Omizzolo, Alessandro; Cesare, Barbieri; Blanco, Carlo; Bucciarelli, Beatrice; di Paola, Andrea; Nesci, Roberto

    The photographic plate archives of telescopes around the world contain a veritable treasury of astronomical data. Unfortunately the emulsion is a volatile support and full exploitation of the scientific content is more and more difficult. A large-scale two-year project to digitize the archive of plates of the Italian Astronomical Observatories and of the Specola Vaticana has been started in 2002 with funds from the Ministry of the University and Research following a pilot program funded by the University of Padova in 2001. Identical systems composed by a high quality commercial scanner plus dedicated personal computers and acquisition software (developed initially at DLR Berlin) have been installed in all participating Institutes. Three main goals make up the total project: to provide high quality photometric sequences with the Campo Imperatore telescopes to be used on the scanned plates to perform astrometric measures taking advantage of the large span of time covered by the plates and to distribute the digitized information to all interested researchers via the international Web. This paper presents some of the activities carried out and results obtained so far

  6. A New Test of Plate Tectonics.

    ERIC Educational Resources Information Center

    Shea, James Herbert

    1989-01-01

    Discussed are two techniques that can be used to directly test the theory that the plates which make up the crust of the earth are still moving. Described are the use of satellite laser ranging and very long baseline interferometry. Samples of data and their analysis are provided. (CW)

  7. X-Band/Ka-Band Dichroic Plate

    NASA Technical Reports Server (NTRS)

    Chen, Jacqueline C.

    1993-01-01

    Dichroic plate designed nearly transparent to circularly polarized microwaves at frequencies between 31.8 and 34.7 GHz (in and near Ka band) and reflective at frequencies between 8.4 and 8.5 GHz (in the X band). Made of electrically conductive material and contains rectangular holes in staggered pattern.

  8. Ultralight shape-recovering plate mechanical metamaterials

    PubMed Central

    Davami, Keivan; Zhao, Lin; Lu, Eric; Cortes, John; Lin, Chen; Lilley, Drew E.; Purohit, Prashant K.; Bargatin, Igor

    2015-01-01

    Unusual mechanical properties of mechanical metamaterials are determined by their carefully designed and tightly controlled geometry at the macro- or nanoscale. We introduce a class of nanoscale mechanical metamaterials created by forming continuous corrugated plates out of ultrathin films. Using a periodic three-dimensional architecture characteristic of mechanical metamaterials, we fabricate free-standing plates up to 2 cm in size out of aluminium oxide films as thin as 25 nm. The plates are formed by atomic layer deposition of ultrathin alumina films on a lithographically patterned silicon wafer, followed by complete removal of the silicon substrate. Unlike unpatterned ultrathin films, which tend to warp or even roll up because of residual stress gradients, our plate metamaterials can be engineered to be extremely flat. They weigh as little as 0.1 g cm−2 and have the ability to ‘pop-back' to their original shape without damage even after undergoing multiple sharp bends of more than 90°. PMID:26632595

  9. 30 CFR 18.11 - Approval plate.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Approval plate. 18.11 Section 18.11 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR TESTING, EVALUATION, AND APPROVAL OF... the applicant, and spaces for the approval number, serial number, and the type or model of machine....

  10. Micro-channel plates and vacuum detectors

    NASA Astrophysics Data System (ADS)

    Gys, T.

    2015-07-01

    A micro-channel plate is an array of miniature electron multipliers that are each acting as a continuous dynode chain. The compact channel structure results in high spatial and time resolutions and robustness to magnetic fields. Micro-channel plates have been originally developed for night vision applications and integrated as an amplification element in image intensifiers. These devices show single-photon sensitivity with very low noise and have been used as such for scintillating fiber tracker readout in high-energy physics experiments. Given their very short transit time spread, micro-channel plate photomultiplier tubes are also being used in time-of-flight and particle identification detectors. The present paper will cover the history of the micro-channel plate development, basic features, and some of their applications. Emphasis will be put on various new manufacturing processes that have been developed over the last few years, and that result in a significant improvement in terms of efficiency, noise, and lifetime performance.

  11. Equal Plate Charges on Series Capacitors?

    ERIC Educational Resources Information Center

    Illman, B. L.; Carlson, G. T.

    1994-01-01

    Provides a line of reasoning in support of the contention that the equal charge proposition is at best an approximation. Shows how the assumption of equal plate charge on capacitors in series contradicts the conservative nature of the electric field. (ZWH)

  12. Structural Assembly for Cold Plate Cooling

    NASA Technical Reports Server (NTRS)

    Zaffetti, Mark A. (Inventor); Taddey, Edmund P. (Inventor)

    2014-01-01

    A device including a structural member having a heat spreader and an electronic device mounted directly to a first surface of the heat spreader of the structural member. The device also includes a cold plate mounted directly to the first surface of the heat spreader of the structural member.

  13. Bending of skew plates of variable rigidity.

    NASA Technical Reports Server (NTRS)

    Willems, N.; Mahmood, S. S.

    1972-01-01

    Description of an analytical procedure for studying the bending of thin skew plates of a thickness varying in one direction, under arbitrary lateral loading. The analysis was programmed for execution on an electronic computer for various conditions and types of loading. The results obtained suggest that the proposed analytical procedure is more accurate than the finite-difference technique used in earlier investigations.

  14. BEPLATE emdash simulation of electrochemical plating

    SciTech Connect

    Giles, G.E. ); Gray, L.J. ); Bullock, J.S. IV )

    1990-09-01

    BEPLATE is a FORTRAN code that uses the boundary element method to simulate the electrochemical plating of material on parts, primarily rotating axisymmetric parts. A boundary element technique is used to solve for the local current density and thus the plating rate on the part, which is used to calculate the growth in the plated layer over a user-specified time step. The surface is moved to reflect this growth, and the new surface is used to generate the local current density. This cycle is repeated until the final time specified by the analyst, producing the final plated thickness. BEPLATE includes models for the polarization effects at both the part (cathode) and anode and allows the use of symmetry planes and nonconducting shields. For electroplating simulations, the part shape is normally assumed to be axisymmetric with a centerline along the z-axis. More general part shapes can be analyzed by BEPLATE if the surface growth simulation is not needed. In either case, the shield, anode, and tank geometries are not restricted to specific shapes. This report includes the information required to run BEPLATE, specifically, a brief description of the BEPLATE system including hardware and software requirements, a description of the complete simulation process, discussion of rules for generating models, and additional reference material. This system of codes consists of model generators (PIGS or PATRAN), input processor (BEPIN), the simulation code (BEPLATE) and postprocessing codes (PATRAN or CONPLOT).

  15. Phase-Scrambler Plate Spreads Point Image

    NASA Technical Reports Server (NTRS)

    Edwards, Oliver J.; Arild, Tor

    1992-01-01

    Array of small prisms retrofit to imaging lens. Phase-scrambler plate essentially planar array of small prisms partitioning aperture of lens into many subapertures, and prism at each subaperture designed to divert relatively large diffraction spot formed by that subaperture to different, specific point on focal plane.

  16. Titanium carbide bipolar plate for electrochemical devices

    DOEpatents

    LaConti, Anthony B.; Griffith, Arthur E.; Cropley, Cecelia C.; Kosek, John A.

    2000-07-04

    A corrosion resistant, electrically conductive, non-porous bipolar plate is made from titanium carbide for use in an eletrochemical device. The process involves blending titanium carbide powder with a suitable binder material, and molding the mixture, at an elevated temperature and pressure.

  17. Industrialization of the ion plating process

    NASA Technical Reports Server (NTRS)

    Spalvins, T.

    1976-01-01

    A new process referred to as ion plating by induction heating (IPIH) is described, which combines the advantages of both ion plating and induction heating. The IPIH apparatus consists of the specimen (cathode) to be coated and the evaporation heating source, which is a ceramic crucible containing the metal to be heated. The specimen is an internal part of the high-voltage ceramic-metal vacuum feedthrough and is connected to the negative terminal of the high-voltage power supply, the positive terminal of the power supply being grounded. The plating conditions are the same as those most commonly used in industrial ion plating. A number of metals - such as nickel, iron, platinum - which were practically impossible to deposit by resistance heating evaporation can now be effectively evaporated and deposited to any desired thickness. Excellent adherence is observed for many metals deposited on various metal surfaces in thicknesses from 0.15 to 50 microns, regardless of the materials selected for coating and substrate.

  18. Fabrication procedures for HFIR control plates

    SciTech Connect

    Bowden, G.A.; Hicks, G.R.; Knight, R.W.

    1984-10-01

    The HFIR control system uses Alclad cylindrically shaped components, which have regions containing 31 vol % Eu/sub 2/O/sub 3/ and 38 vol % Ta, respectively. Exacting control of the water passage between these components and adjacent reactor parts is mandatory, and precise dimensional control of the finished products is required. This report describes the procedures developed for manufacturing outer control plates and inner control cylinders. Results are cited which demonstrate that circular-shaped outer control plates can be produced with less than 0.025-in. variation from the specified 9.300-in. radius in any region of the plate. Other results show that, by the exercise of careful control, inner control, inner control plates can be welded into cylindrical geometry with diametrical variations held to less than +- 0.010 in. of the intended 17.846-in. average diam. The cylinders can then be explosively sized, while under compression, with diametric variations of less than 0.005 in. while controlling roundness variations to less than 0.030 in. from the specified 17.842-in. finished diam.

  19. Magnetically excited flexural plate wave apparatus

    DOEpatents

    Martin, S.J.; Butler, M.A.; Frye, G.C.; Smith, J.H.

    1998-11-17

    A non-piezoelectric flexural plate wave apparatus having meander-line transducers mounted on a non-piezoelectric membrane is disclosed. A static magnetic field is directed perpendicularly to the conductive legs of the transducers in the plane of the membrane. Single-port, two-port, resonant, non-resonant, eigenmode, and delay-line modes may be employed. 15 figs.

  20. Magnetically excited flexural plate wave apparatus

    DOEpatents

    Martin, Stephen J.; Butler, Michael A.; Frye, Gregory C.; Smith, James H.

    1998-01-01

    A non-piezoelectric flexural plate wave apparatus having meander-line transducers mounted on a non-piezoelectric membrane. A static magnetic field is directed perpendicularly to the conductive legs of the transducers in the plane of the membrane. Single-port, two-port, resonant, non-resonant, eigenmode, and delay-line modes may be employed.

  1. Experimental investigation on fracture of layered plates

    NASA Astrophysics Data System (ADS)

    Agnihotri, Servesh; Parameswaran, Venkitanarayanan

    2015-03-01

    Layered structures, used in many applications such as windshields, thermal protection systems, heavy armor etc., are comprised of layers having different elastic and fracture properties. Present study focuses on understanding the behavior of cracks in a layered plate oriented in such a way that there are property jumps across the crack front. Two layer plates were fabricated by joining Polymethylmethacrylate (PMMA) and epoxy sheets using an epoxy based adhesive (Araldite). Single edge notched specimens were subjected to mixed mode loading using the asymmetric four point bending configuration. The results of the study indicated that the failure in two layer plates is progressive in nature. Crack extension starts in the most vulnerable layer (epoxy) first and the crack grows in a sequence of jumps and arrests in this layer. Once this crack reaches a particular length the crack in the second layer starts extending resulting in final failure of the plate. Similar sequence of events was observed in the case of dynamically loaded samples. The predictions of the load at which epoxy crack starts growing and the angle at which the crack grows using the maximum tensile stress criteria were in reasonable agreement with the experimentally observed values.

  2. Plate forming and break down pizza box

    DOEpatents

    Pantisano, Frank; Devine, Scott M.

    1992-01-01

    A standard corrugated paper pizza box is provided with slit cuts cut through the top panel of the pizza box in a shape to form four circular serving plates with a beveled raised edge and cross slit cuts through the bottom panel of the pizza box separating the box into four essentially equal portions for easy disposal.

  3. History and Evolution of Precambrian plate tectonics

    NASA Astrophysics Data System (ADS)

    Fischer, Ria; Gerya, Taras

    2014-05-01

    Plate tectonics is a global self-organising process driven by negative buoyancy at thermal boundary layers. Phanerozoic plate tectonics with its typical subduction and orogeny is relatively well understood and can be traced back in the geological records of the continents. Interpretations of geological, petrological and geochemical observations from Proterozoic and Archean orogenic belts however (e.g., Brown, 2006), suggest a different tectonic regime in the Precambrian. Due to higher radioactive heat production the Precambrian lithosphere shows lower internal strength and is strongly weakened by percolating melts. The fundamental difference between Precambrian and Phanerozoic tectonics is therefore the upper-mantle temperature, which determines the strength of the upper mantle (Brun, 2002) and the further tectonic history. 3D petrological-thermomechanical numerical modelling experiments of oceanic subduction at an active plate at different upper-mantle temperatures show these different subduction regimes. For upper-mantle temperatures < 175 K above the present day value a subduction style appears which is close to present day subduction but with more frequent slab break-off. At upper-mantle temperatures 175 - 250 K above present day values steep subduction continues but the plates are weakened enough to allow buckling and also lithospheric delamination and drip-offs. For upper-mantle temperatures > 250 K above the present day value no subduction occurs any more. The whole lithosphere is delaminating and due to strong volcanism and formation of a thicker crust subduction is inhibited. This stage of 200-250 K higher upper mantle temperature which corresponds roughly to the early Archean (Abbott, 1994) is marked by strong volcanism due to sublithospheric decompression melting which leads to an equal thickness for both oceanic and continental plates. As a consequence subduction is inhibited, but a compressional setup instead will lead to orogeny between a continental

  4. Cell separator plate used in fuel cell stacks

    SciTech Connect

    Reznikov, G.L.

    1993-08-03

    In a fuel cell stack comprising a plurality of fuel cell units, each said fuel cell unit is described comprising an anode, a cathode, an electrolyte in contact on one side with the electrolyte facing face of said anode and in contact on the opposite side with the electrolyte facing face of said cathode, and a separator plate forming an anode chamber between the anode facing face of said separator plate and said separator plate facing face of said anode and said separator plate forming a cathode chamber between the opposite cathode facing face of said separator plate and the separator plate facing face of the cathode of an adjacent said fuel cell unit, said anode chamber in gas communication with fuel gas supply and outlet and said cathode chamber in gas communication with oxidant supply and outlet, the improvement comprising; said electrolyte terminating inwardly from the periphery of said separator plate, said separator plate having a electrolyte seal structure extending outwardly from each face, said electrolyte seal structure contacting the periphery of said electrolyte completely around the periphery of said electrolyte forming a separator plate/electrolyte seal under cell operating conditions, said separator plate extending beyond the periphery of said electrolyte and having a separator plate peripheral seal structure spaced beyond the periphery of said electrolyte and extending outwardly from each face of said separator plate, and sealing means at said separator plate peripheral seal structure to form with adjacent separator plates when in said fuel cell stack a peripheral separator plate seal completely around the periphery of said separator plate thereby forming a peripheral compartment between said separator plate/electrolyte seal and said peripheral separator plate seal.

  5. Spirit Says Goodbye to 'Home Plate'

    NASA Technical Reports Server (NTRS)

    2006-01-01

    For the past several weeks, Spirit has been examining spectacular layered rocks exposed at 'Home Plate.' The rover has been driving around the northern and eastern edges of Home Plate, on the way to 'McCool Hill.' Before departing, Spirit took this image showing some of the most complex layering patterns seen so far at this location.

    The layered nature of these rocks presents new questions for the rover team. In addition to their chemical properties, which scientists can study using Spirit's spectrometers, these rocks record a detailed history of the physical properties that formed them. In the center of this image, one group of layers slopes downward to the right. The layers above and below this group are more nearly horizontal. Where layers of different orientations intersect, other layers are truncated. This indicates that there were complex patterns of alternating erosion and deposition occurring when these layers were being deposited. Similar patterns can be found in some sedimentary rocks on Earth. Physical relationships among the various layers exposed at Home Plate are crucial evidence in understanding how these Martian rocks formed. Scientists suspect that the rocks at Home Plate were formed in the aftermath of a volcanic explosion or impact event, and they are investigating the possibility that wind may also have played a role in redistributing materials after such an event.

    Images like this one from panoramic camera (Pancam), which shows larger-scale layering, as well as those from the microscopic imager, which reveal the individual sand-sized grains that make up these rocks, are essential to understanding the geologic history of Home Plate.

    This view is an approximately true-color rendering that combines separate images taken through the Pancam's 753-nanometer, 535-namometer, and 432-nanometer filters during Spirit's 774th Martian day (March 8, 2006).

  6. The turbulent wake behind side-by-side plates

    NASA Astrophysics Data System (ADS)

    Hoseini Dadmarzi, Fatemeh; Narasimhamurthy, Vagesh D.; Andersson, Helge I.; Pettersen, Bjørnar

    2011-12-01

    The wake behind two flat plates placed side by side normal to the inflow has been investigated by direct numerical simulation. The spacing between the two plates is one plate width d and the Reynolds number based on the plate width and inflow velocity is 1000. Flow pattern study indicates an anti-phase vortex shedding behind flat plates in the near wake which merges to one large wake downstream. Such a vortex structure has not been observed behind the flat plates for this gap ratio.

  7. Creep analysis of fuel plates for the Advanced Neutron Source

    SciTech Connect

    Swinson, W.F.; Yahr, G.T.

    1994-11-01

    The reactor for the planned Advanced Neutron Source will use closely spaced arrays of fuel plates. The plates are thin and will have a core containing enriched uranium silicide fuel clad in aluminum. The heat load caused by the nuclear reactions within the fuel plates will be removed by flowing high-velocity heavy water through narrow channels between the plates. However, the plates will still be at elevated temperatures while in service, and the potential for excessive plate deformation because of creep must be considered. An analysis to include creep for deformation and stresses because of temperature over a given time span has been performed and is reported herein.

  8. Empty plates and larger waists: a cross-sectional study of factors associated with plate clearing habits and body weight.

    PubMed

    Robinson, E; Hardman, C A

    2016-06-01

    Clearing one's plate out of habit when eating may promote excess energy consumption. This study examined whether plate clearing is related to increased body weight in a sample of young adults. It also sought to identify potential determinants of plate clearing. A cross-sectional design was used in which 385 young adults from a UK university completed self-report measures of plate clearing, weight and height, and demographic characteristics. Plate clearing was predictive of heavier body weight in both unadjusted and adjusted analyses. Parental encouragement to clear one's plate during childhood (retrospectively reported) and personal concerns about food waste were both independent predictors of plate clearing tendencies. Clearing one's plate when eating is associated with heavier body weight, and the prevalence of this behaviour may depend on parenting practices and concerns about food waste. Further work examining the longitudinal effect of plate clearing on weight gain is now needed. PMID:26695723

  9. A higher order plate theory for dynamic stability analysis of delaminated composite plates

    NASA Astrophysics Data System (ADS)

    Chattopadhyay, A.; Radu, A. G.; Dragomir-Daescu, D.

    A higher order shear deformation theory is used to investigate the instability associated with delaminated composite plates subject to dynamic loads. Both transverse shear and rotary inertia effects are taken into account. The procedure is implemented using the finite element method. Delamination is modeled using the penalty parameter approach. The natural frequencies are computed and compared with NASTRAN 3D results and available experimental data. The effect of delamination on the critical buckling load and the first two instability regions is investigated for various loading conditions, plate thickness and boundary conditions. As expected the natural frequencies and the critical buckling load of the delaminated plate are lower than those of the nondelaminated plate. They decrease with increase in delamination length. Increase in delamination length causes instability regions to be shifted to lower parametric resonance frequencies and the normalized width of the instability regions to increase.

  10. Fuel cell plates with improved arrangement of process channels for enhanced pressure drop across the plates

    SciTech Connect

    Spurrier, Francis R.; Pierce, Bill L.; Wright, Maynard K.

    1986-01-01

    A plate for a fuel cell has an arrangement of ribs defining an improved configuration of process gas channels and slots on a surface of the plate which provide a modified serpentine gas flow pattern across the plate surface. The channels are generally linear and arranged parallel to one another while the spaced slots allow cross channel flow of process gas in a staggered fashion which creates a plurality of generally mini-serpentine flow paths extending transverse to the longitudinal gas flow along the channels. Adjacent pairs of the channels are interconnected to one another in flow communication. Also, a bipolar plate has the aforementioned process gas channel configuration on one surface and another configuration on the opposite surface. In the other configuration, there are not slots and the gas flow channels have a generally serpentine configuration.

  11. Acoustic Plate Mode sensing in liquids based on free and electrically shorted plate surfaces.

    PubMed

    Anisimkin, V I; Caliendo, C; Verona, E

    2016-05-01

    The sensing behavior to liquids for Acoustic Plate Modes (APMs) propagating along 64°Y, 90°X LiNbO3 plate was investigated vs. two electric boundary conditions. The changes in the APMs phase velocity and attenuation were measured upon exposure to different liquids wetting one of the surfaces of the plate, either free or electrically shorted by a thin conductive Al layer. The experimental data confirm that the presence of a metallic layer covering one of the plate surfaces affects the viscosity and temperature sensitivity of the device. The differences between the sensor response for various liquids, with free or metalized faces, are interpreted in terms of the APM polarization. PMID:26901669

  12. Using explosion-clad plates of alloy 625 in flue gas desulfurization plates

    SciTech Connect

    Kirchheiner, R.; Hoffmann, T.; Hofmann, F.

    1987-01-01

    Various concepts may be used to line large vessels with high quality corrosion resistant plates. Explosive cladding with alloy 625 on mild steel base plates is one method that is currently used for FGD adsorption towers in the Federal Republic of Germany. Cladding technology, i.e. welding, is very critical for this method, and both the weld filler metals and process parameters and the processes themselves have to be precisely matched.

  13. 4-D Subduction Models Incorporating an Upper Plate

    NASA Astrophysics Data System (ADS)

    Stegman, D.; Capitanio, F. A.; Moresi, L.; Mueller, D.; Clark, S.

    2007-12-01

    Thus far, relatively simplistic models of free subduction have been employed in which the trench and plate kinematics are emergent features completely driven by the negative buoyancy of the slab. This has allowed us to build a fundamental understanding of subduction processes such as the kinematics of subduction zones, the strength of slabs, and mantle flow-plate coupling. Additionaly, these efforts have helped to develop appreciable insight into subduction processes when considering the energetics of subduction, in particular how energy is dissipated in various parts of the system such as generating mantle flow and bending the plate. We are now in a position to build upon this knowledge and shift our focus towards the dynamic controls of deformation in the upper plate (vertical motions, extension, shortening, and dynamic topography). Here, the state of stress in the overriding plate is the product of the delicate balance of large tectonic forces in a highly-coupled system, and must therefore include all components of the system: the subducting plate, the overriding plate, and the underlying mantle flow which couples everything together. We will present some initial results of the fully dynamic 3-D models of free subduction which incorporate an overriding plate and systematically investigate how variations in the style and strength of subduction are expressed by the tectonics of the overriding plate. Deformation is driven in the overriding plate by the forces generated from the subducting plate and the type of boundary condition on the non-subducting side of the overriding plate (either fixed or free). Ultimately, these new models will help to address a range of issues: how the overriding plate influences the plate and trench kinematics; the formation and evolution of back-arc basins; the variation of tractions on the base of the overriding plate; the nature of forces which drive plates; and the dynamics controls on seismic coupling at the plate boundary.

  14. Absolute plate velocities from seismic anisotropy: Importance of correlated errors

    NASA Astrophysics Data System (ADS)

    Zheng, Lin; Gordon, Richard G.; Kreemer, Corné

    2014-09-01

    The errors in plate motion azimuths inferred from shear wave splitting beneath any one tectonic plate are shown to be correlated with the errors of other azimuths from the same plate. To account for these correlations, we adopt a two-tier analysis: First, find the pole of rotation and confidence limits for each plate individually. Second, solve for the best fit to these poles while constraining relative plate angular velocities to consistency with the MORVEL relative plate angular velocities. Our preferred set of angular velocities, SKS-MORVEL, is determined from the poles from eight plates weighted proportionally to the root-mean-square velocity of each plate. SKS-MORVEL indicates that eight plates (Amur, Antarctica, Caribbean, Eurasia, Lwandle, Somalia, Sundaland, and Yangtze) have angular velocities that differ insignificantly from zero. The net rotation of the lithosphere is 0.25 ± 0.11° Ma-1 (95% confidence limits) right handed about 57.1°S, 68.6°E. The within-plate dispersion of seismic anisotropy for oceanic lithosphere (σ = 19.2°) differs insignificantly from that for continental lithosphere (σ = 21.6°). The between-plate dispersion, however, is significantly smaller for oceanic lithosphere (σ = 7.4°) than for continental lithosphere (σ = 14.7°). Two of the slowest-moving plates, Antarctica (vRMS = 4 mm a-1, σ = 29°) and Eurasia (vRMS = 3 mm a-1, σ = 33°), have two of the largest within-plate dispersions, which may indicate that a plate must move faster than ≈ 5 mm a-1 to result in seismic anisotropy useful for estimating plate motion. The tendency of observed azimuths on the Arabia plate to be counterclockwise of plate motion may provide information about the direction and amplitude of superposed asthenospheric flow or about anisotropy in the lithospheric mantle.

  15. The motion induced between a rotating plate and a radially stretching or shrinking plate

    NASA Astrophysics Data System (ADS)

    Weidman, Patrick D.; Perocco, Enrico L. M.

    2016-02-01

    The flow induced between parallel plates separated by a distance h executing different types of in-plane motion is investigated. The upper plate radially stretches at strain rate a and the lower plate rotates at angular velocity Ω about a common axis. A similarity solution form reduces the Navier-Stokes equations to a coupled pair of ordinary differential equations in two parameters: R = |a| h2/ν and σ = Ω/|a|, where ν is the kinematic viscosity of the fluid. Solutions are obtained for both stretching and shrinking upper plates and numerical results for pressure gradient and wall shear stress parameters are found and compared with low-R series solutions and large-R asymptotic behaviors. Sample radial and azimuthal velocity profiles reveal regions of zero radial and azimuthal wall shear stress which are studied in detail. This work represents the first study of the flow induced between parallel plates for which each plate executes a different type of in-plane motion.

  16. Parallel plate waveguide with anisotropic graphene plates: Effect of electric and magnetic biases

    NASA Astrophysics Data System (ADS)

    Malekabadi, Ali; Charlebois, Serge A.; Deslandes, Dominic

    2013-03-01

    The performances of a parallel plate waveguide (PPWG) supported by perfect electric conductor (PEC)-graphene and graphene-graphene plates are evaluated. The graphene plate behavior is modeled as an anisotropic medium with both diagonal and Hall conductivities derived from Kubo formula. The PPWG modes supported by PEC-graphene and graphene-graphene plates are studied. Maxwell's equations are solved for these two waveguides, while the graphene layers are biased with an electric field only and with both electric and magnetic fields. It is shown that when both electric and magnetic biases are applied to the graphene, a hybrid mode (simultaneous transverse electric (TE) and transverse magnetic (TM) modes) will propagate inside the waveguide. The intensity of each TE and TM modes can be adjusted with the applied external bias fields. Study of different waveguides demonstrates that by decreasing the plate separation (d), the wave confinement improves. However, it increases the waveguide attenuation. A dielectric layer inserted between the plates can also be used to improve the wave confinement. The presented analytical procedure is applicable to other guiding structures having walls with isotropic or anisotropic conductivities.

  17. Entropy Generation During Fluid Flow Between Two Parallel Plates With Moving Bottom Plate

    NASA Astrophysics Data System (ADS)

    Erbay, Latife B.; Ercan, Mehmet S.; Sülüs, Birsen; Yalçÿn, M. M.

    2003-12-01

    Two dimensional numerical analysis of entropy generation during transient convective heat transfer for laminar flow between two parallel plates has been investigated. The fluid is incompressible and Newtonian and the flow is the hydrodynamically and thermally developing. The plates are held at constant equal temperatures higher than that of the fluid. The bottom plate moves in either parallel or in inverse direction to the flow. The governing equations of the transient convective heat transfer are written in two-dimensional Cartesian coordinates and solved by the finite volume method with SIMPLE algorithm. The solutions are carried for Reynolds numbers of 102, 5x102 and 103 and Prandtl number of 1. After the flow field and the temperature distributions are obtained, the entropy values and the sites initiating the entropy generation are investigated. The results have indicated that the number of the entropy generation has its highest value at the highest Reynolds and Br/Ω values, which is obtained at counter motion of the lower plate. The lowest average number of the entropy generation on the bottom plate is obtained in parallel motion. The corners of the channel plates at the entrance play the role of active sites where the generation of entropy is triggered.

  18. Writing and Visualization for Teaching Plate Tectonics

    NASA Astrophysics Data System (ADS)

    Thomas, S. F.

    2004-12-01

    The Theory of Plate Tectonics is probably the most important paradigm for understanding the workings of our planet. As such it is an integral part in any Introductory Geology course. Whereas geology majors usually easily embrace the Theory of Plate Tectonics, the enthusiasm for the coherence and elegance of this theory appears to be much more subdued among the majority of non-science majors. While visual and electronic media certainly support the teaching of the theory, pretty pictures and animations are not sufficient for many non-science majors to grasp the concepts of interacting lithospheric plates. It is well known that students do better in learning scientific concepts if they create their own understanding through research and inquiry-based learning, by working in the field, manipulating real earth-science data, and through writing. Writing assignments give instructors the opportunity to assess their students' learning and to clarify misconceptions yet they also have to be willing to teach students how to craft a science paper. Most electronic media and textbook-added CD-ROMs are not useful for making the structure of a science paper transparent. I found many of the necessary ingredients for effectively teaching plate tectonics in the interactive CD-ROM, "Our Dynamic Planet", developed by Wm. Prothero together with G. Kelly (University of California at Santa Barbara). It allows students to select and manipulate real earth-science data of plate-tectonically active regions, and provides an electronic interface that lets students create graphical representations of their collected data. A downloadable Teacher's Manual provides suggestions on teaching students to write a scientific argument, rooted in sound pedagogy. Originally designed for a large oceanography class, the material was modified for use in a small introductory geology class for non-science majors. Various assignments were given to instruct students in writing a scientific argument based on their

  19. The Rivera-Cocos Plate Boundary Revisited

    NASA Astrophysics Data System (ADS)

    Bandy, W. L.; Mortera-Gutierrez, C. A.; Michaud, F.; Ortega Ramírez, J.

    2013-05-01

    The nature of the boundary between the Rivera and Cocos plates has long been controversial. Early studies (predominantly earthquake studies) suggested that it was a NE oriented left lateral transform boundary. With the collection of multi-beam bathymetric data during the SEAMAT cruise of the N/O Jean Charcot in 1987 it became clear that this early proposal was not entirely correct as no clear transform morphology was observed. Shortly after the SEAMAT campaign, three main proposals emerged to explain this lack of transform morphology. The first two proposals favored the results of earthquake studies over the new multibeam data. The first proposed that the boundary is indeed a left-lateral transform boundary, you just cannot see it. In other words, it was a diffuse boundary and the resolution of the multi-beam data was not sufficient to reveal the associated deformation. The second proposal was that it was an east-west oriented, dextral transform, the proposal being based on the results of an earthquake directivity analysis. The third proposal favored the morphologic data over the earthquake data and proposed that the plate boundary was not a transform boundary, but was instead a divergent boundary, at least near the Middle America Trench in what is now called the EL Gordo Graben. Implicit in this proposal was that the earthquake activity did not reflect plate motions but rather were the result of local stresses. Since 2002, several marine geophysical campaigns have been conducted in the area of the Rivera-Cocos plate boundary with the aim of resolving this debate. During the 2002 BART and FAMEX campaigns of the N/O L'ATALANTE, multibeam bathymetric and seafloor backscatter data were collected along the boundary. During the MARTIC04 and MARTIC05 campaigns of the B/O EL PUMA dense total field magnetic surveys were conducted covering the entire plate boundary. Lastly, the multibeam coverage obtained during the BART/FAMEX campaigns was extended northward during the

  20. Flat plate puncture test convergence study.

    SciTech Connect

    Snow, Spencer; Ammerman, Douglas James; Molitoris, David; Tso, Chi-Fung; Yaksh, Mike

    2010-10-01

    The ASME Task Group on Computational Mechanics for Explicit Dynamics is investigating the types of finite element models needed to accurately solve various problems that occur frequently in cask design. One type of problem is the 1-meter impact onto a puncture spike. The work described in this paper considers this impact for a relatively thin-walled shell, represented as a flat plate. The effects of mesh refinement, friction coefficient, material models, and finite element code will be discussed. The actual punch, as defined in the transport regulations, is 15 cm in diameter with a corner radius of no more than 6 mm. The punch used in the initial part of this study has the same diameter, but has a corner radius of 25 mm. This more rounded punch was used to allow convergence of the solution with a coarser mesh. A future task will be to investigate the effect of having a punch with a smaller corner radius. The 25-cm thick type 304 stainless steel plate that represents the cask wall is 1 meter in diameter and has added mass on the edge to represent the remainder of the cask. The amount of added mass to use was calculated using Nelm's equation, an empirically derived relationship between weight, wall thickness, and ultimate strength that prevents punch through. The outer edge of the plate is restrained so that it can only move in the direction parallel to the axis of the punch. Results that are compared include the deflection at the edge of the plate, the deflection at the center of the plate, the plastic strains at radius r=50 cm and r=100 cm , and qualitatively, the distribution of plastic strains. The strains of interest are those on the surface of the plate, not the integration point strains. Because cask designers are using analyses of this type to determine if shell will puncture, a failure theory, including the effect of the tri-axial nature of the stress state, is also discussed. The results of this study will help to determine what constitutes an adequate

  1. Optics for People Stuck in Traffic: License Plates.

    ERIC Educational Resources Information Center

    Chagnon, Paul

    1995-01-01

    Explains the theory behind the working of Scotchlite, a retrodirective material used for coating automotive license plates, and the Ensure Imaging System that allows law enforcement officers to verify the authenticity of the plate. (JRH)

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

    DOEpatents

    Louis, G.A.

    1984-05-29

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

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

    DOEpatents

    Louis, George A.

    1986-08-05

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

  4. Aluminum/steel wire composite plates exhibit high tensile strength

    NASA Technical Reports Server (NTRS)

    1966-01-01

    Composite plate of fine steel wires imbedded in an aluminum alloy matrix results in a lightweight material with high tensile strength. Plates have been prepared having the strength of titanium with only 85 percent of its density.

  5. Undercoat prevents blistering of silver plating at elevated temperatures

    NASA Technical Reports Server (NTRS)

    Kuster, C. A.

    1967-01-01

    Gold undercoat prevents blistering in the silver plating of Inconel 718 seals from steam at high temperatures. The undercoat is diffused into the surface of the parent metal by baking prior to silver plating.

  6. 32. DETAIL OF BOARD ROOM CHAIR WITH SILVER PLATE LISTING ...

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

    32. DETAIL OF BOARD ROOM CHAIR WITH SILVER PLATE LISTING NAMES AND DATES OF PAST OCCUPANTS AND PLATE WITH NAME OF CURRENT OCCUPANT - Philadelphia Saving Fund Society, Twelfth & Market Streets, Philadelphia, Philadelphia County, PA

  7. A Simple Class Exercise on Plate Tectonic Motion.

    ERIC Educational Resources Information Center

    Bates, Denis E. B.

    1990-01-01

    Presented is an activity in which students construct a model of plate divergence with two sheets of paper to show the separation of two continental plates in a system of spreading ridges and faults. Diagrams and procedures are described. (CW)

  8. Electric alignment of plate shaped clay aggregates in oils

    NASA Astrophysics Data System (ADS)

    Castberg, Rene; Rozynek, Zbigniew; Måløy, Knut Jørgen; Flekkøy, Eirik

    2016-01-01

    We experimentally investigate the rotation of plate shaped aggregates of clay mineral particles immersed in silicone oil. The rotation is induced by an external electric field. The rotation time is measured as a function of the following parameters: electric field strength, the plate geometry (length and width) and the dielectric properties of the plates. We find that the plates always align with their longest axis parallel to the direction of the electric field (E), independently of the arrangement of individual clay ‑2 mineral particles within the plate. The rotation time is found to scale as E and is proportional to the viscosity (μ), which coincides well with a model that describes orientation of dipoles in electric fields. As the length of the plate is increased we quantify a difference between the longitudinal and transverse polarisability. Finally, we show that moist plates align faster. We attribute this to the change of the dielectric properties of the plate due to the presence of water.

  9. Method of assembling a plate-fin heat exchanger

    SciTech Connect

    Kopczynski, J.F.

    1986-07-22

    A method is described of assembling a plate-fin heat exchanger comprising the steps of providing like substantially straight elongate plate fins with spaced holes therein, bowing the plate-fins to increase their stability and accumulating the plate fins in a stacked contiguous relationship to provide a bundle, providing elongated substantially parallel tubes spaced from each other substantially the same distance as the spaced holes and oriented substantially perpendicularly to the stacked plate fins, and mounting the plate fins in the stacked contiguous relationship onto the elongated substantially parallel tubes by inserting the substantially parallel tubes into the spaced holes, transferring the bundle of bowed plate-fins into a carriage, and transferring the bundle of plate-fins from the carriage onto the elongated substantially parallel tubes.

  10. 49 CFR 179.220-6 - Thickness of plates.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... required bursting pressure in psig; S = Minimum tensile strength of plate material in p.s.i. as prescribed... pressure in psig; S = Minimum tensile strength of plate material in psi as prescribed in AAR...

  11. 49 CFR 179.220-6 - Thickness of plates.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... required bursting pressure in psig; S = Minimum tensile strength of plate material in p.s.i. as prescribed... pressure in psig; S = Minimum tensile strength of plate material in psi as prescribed in AAR...

  12. 49 CFR 179.220-6 - Thickness of plates.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... required bursting pressure in psig; S = Minimum tensile strength of plate material in p.s.i. as prescribed... pressure in psig; S = Minimum tensile strength of plate material in psi as prescribed in AAR...

  13. Fringe Capacitance of a Parallel-Plate Capacitor.

    ERIC Educational Resources Information Center

    Hale, D. P.

    1978-01-01

    Describes an experiment designed to measure the forces between charged parallel plates, and determines the relationship among the effective electrode area, the measured capacitance values, and the electrode spacing of a parallel plate capacitor. (GA)

  14. Application of amorphous brush-plated

    NASA Astrophysics Data System (ADS)

    Zheng, M.; Zhu, Y.; Zheng, Z.

    1994-02-01

    The results obtained during industrial trials have shown that the service life of hot work dies can be increased by 33 to 180% using the brush plating technique to prepare amorphous coatings. The coatings possess a much higher hardness, lower friction coefficient at room and elevated temperatures, good scale resistance in addition to higher surface finish, compared to uncoated dies, and thus improve the tribological performance of the dies. In this work, a study of the crystallization process, its kinetics, and the hardness variations of the coatings has been made. According to the data obtained, it can be considered that the main reason for the success of amorphous brush-plated coatings is that, during the operation, crystallization and precipitation takes place instantaneously, which results in a strong secondary hardening effect, thus leading to an increase in the red hardness of the surface layers of dies, therefore ensuring higher thermal wear resistance of the dies.

  15. Variation in CR imaging plate readers.

    PubMed

    Fauber, Terri L; Legg, Jeffrey S; Quinn, Megan

    2002-01-01

    This study investigated computed radiography (CR) image processing to determine whether variation exists within and among CR imaging plate readers. Photostimulable imaging plates were exposed using a phantom test tool and processed in 4 CR readers located in diverse settings in an urban academic medical center. Research results indicate daily variation of S-numbers within individual CR readers did not exceed tolerance limits, although over the 3-week study period, evidence of S-number variation within individual CR readers was mixed. In addition, S-number variability among multiple CR readers was found to be statistically significant. Although the cause of the variability remains unknown, evidence of variability among multiple CR readers indicates a need for systematic quality control. PMID:12362532

  16. Innovative concepts for fuel plate fabrication

    SciTech Connect

    Domagala, R.F.; Wiencek, T.C.; Thresh, H.R.

    1987-10-01

    A number of fabrication concepts have been and are being explored at ANL. Although specific processes were addressed with silicide fuels in mind, most are applicable to fabrication with any fuel type. Processes include improved comminution procedures for converting U-Si alloy ingots to powder using a roll crusher and an impact mill. Aluminizing of core compacts by ion vapor deposition techniques in vacuum offers prospects for improved plate quality. Other items examined include the possible use of coatings on fuel particles, matrices different from pure Al, and ductile fuel alloys which might be used to produce fuel plates with uranium loadings higher than possible with conventional dispersed-phase powder metallurgy technology.

  17. Geology and plate-tectonic development

    SciTech Connect

    Irwin, W.P.

    1990-01-01

    The San Andreas fault is a transform fault along the boundary between the Pacific and North American plates. Bedrock along the fault includes various lithologic units that range in age from Precambrian to Tertiary and younger. Some bedrock units that can be matched across the fault suggest strike-slip displacement of as much as 560 km. This chapter describes geologic formations of northern and central California, including Franciscan rocks, Coast Range ophiolite, Great Valley sequence, Coast Range thrust, Salinian block, displacement of pre-Quaternary rocks by the San Andreas fault, and the relation of geologic structure to seismic behavior. Formations of southern California which are described are the Transverse Ranges and the Salton Trough and displacement of basement rocks by the San Andreas fault. Plate-tectonic development of the San Andreas fault is also discussed.

  18. Intrinsic component mode synthesis and plate vibrations

    NASA Astrophysics Data System (ADS)

    Bourquin, F.; D'Hennezel, F.

    1992-07-01

    A 'fixed-interface' method of component mode synthesis is presented and employed to compute error bounds for the case of Kirchhoff plates. The fixed-interface method exploits particular 'constraint modes' that are used as eigenfunctions for the Poincare-Steklov operator in the domain decomposition. The technique is applied to the computation of error bounds and coupling modes for several variants of plate problems. The definition and number of the component modes required for accurate mode synthesis does not depend on the selected discretization process. This allows the fixed-interface technique to be used for the effective treatment of large 3D elasticity problems with a large number of unknown interfaces.

  19. Nonlinear vibrations of viscoelastic rectangular plates

    NASA Astrophysics Data System (ADS)

    Amabili, Marco

    2016-02-01

    Nonlinear vibrations of viscoelastic thin rectangular plates subjected to normal harmonic excitation in the spectral neighborhood of the lowest resonances are investigated. The von Kármán nonlinear strain-displacement relationships are used and geometric imperfections are taken into account. The material is modeled as a Kelvin-Voigt viscoelastic solid by retaining all the nonlinear terms. The discretized nonlinear equations of motion are studied by using the arclength continuation and collocation method. Numerical results are obtained for the fundamental mode of a simply supported square plate with immovable edges by using models with 16 and 22 degrees of freedom and investigating solution convergence. Comparison to viscous damping and the effect of neglecting nonlinear viscoelastic damping terms are shown. The change of the frequency-response with the retardation time parameter is also investigated as well as the effect of geometric imperfections.

  20. Survey of ion plating sources. [conferences

    NASA Technical Reports Server (NTRS)

    Spalvins, T.

    1979-01-01

    Based on the type of evaporation source, gaseous media and mode of transport, the following is discussed: resistance, electron beam, sputtering, reactive and ion beam evaporation. Ionization efficiencies and ion energies in the glow discharge determine the percentage of atoms which are ionized under typical ion plating conditions. The plating flux consists of a small number of energetic ions and a large number of energetic neutrals. The energy distribution ranges from thermal energies up to a maximum energy of the discharge. The various reaction mechanisms which contribute to the exceptionally strong adherence - formation of a graded sustrate/coating interface are not fully understood, however the controlling factors are evaluated. The influence of process variables on the nucleation and growth characteristics are illustrated in terms of morphological changes which affect the mechanical and tribological properties of the coating.

  1. Transient motion of thick anisotropic plates

    NASA Technical Reports Server (NTRS)

    Nayfeh, Adnan H.; Taylor, Timothy W.

    1991-01-01

    Analyses are developed for the response of anisotropic plate strips to a transient load. The load is taken in the form of a line load of normal stress on the surface or within the body of the strip. The characteristic free vibrational modes of the strip are derived and used to derive the secular equation for this case in closed form and to isolate the mathematical conditions for symmetric and antisymmetric wave mode propagation in completely separate terms. The applied loads are expanded in terms of these normal modes and the response of the plate is obtained by superposition of the appropriate components. Material systems of higher symmetry are contained implicitly in the analysis.

  2. Sputtering and ion plating for aerospace applications

    NASA Technical Reports Server (NTRS)

    Spalvins, T.

    1981-01-01

    Sputtering and ion plating technologies are reviewed in terms of their potential and present uses in the aerospace industry. Sputtering offers great universality and flexibility in depositing any material or in the synthesis of new ones. The sputter deposition process has two areas of interest: thin film and fabrication technology. Thin film sputtering technology is primarily used for aerospace mechanical components to reduce friction, wear, erosion, corrosion, high temperature oxidation, diffusion and fatigue, and also to sputter-construct temperature and strain sensors for aircraft engines. Sputter fabrication is used in intricate aircraft component manufacturing. Ion plating applications are discussed in terms of the high energy evaporant flux and the high throwing power. Excellent adherence and 3 dimensional coverage are the primary attributes of this technology.

  3. Toward a generalized plate motion reference frame

    NASA Astrophysics Data System (ADS)

    Becker, T. W.; Schaeffer, A. J.; Lebedev, S.; Conrad, C. P.

    2015-05-01

    An absolute plate motion (APM) model is required to address issues such as the thermochemical evolution of Earth's mantle. All APM models have to rely on indirect inferences, including those based on hot spots and seismic anisotropy, each with their own set of uncertainties. Here, we explore a seafloor spreading-aligned reference frame. We show that this reference frame fits azimuthal seismic anisotropy in the uppermost mantle very well. The corresponding Euler pole is close to those of hot spot reference frames, ridge motion minimizing models, and geodynamic estimates of net rotation and predicts clear trench motion patterns. We conclude that a net rotation pole guided by the spreading-aligned model (at 64°E, 61°S, with moderate rotation of ˜ 0.2 … 0.3°/Myr) could indeed represent a standard, comprehensive reference frame for present-day plate motions with respect to the deep mantle.

  4. Casimir interaction between holes in a plate

    NASA Astrophysics Data System (ADS)

    Kabat, Daniel; Karabali, Dimitra; Nair, V. P.

    2010-07-01

    We study the leading long-distance attractive force between two holes in a plate arising from a scalar field with Dirichlet boundary conditions on the plate. We use a formalism in which the interaction is governed by a nonlocal field theory which lives on the two holes. The interaction energy is proportional to Q1Q2/r7 at large separation r, where Q1 and Q2 are certain charges associated with the holes. We compute these charges for round and rectangular holes. We show that the 1/r7 behavior is universal for separations large compared to the linear dimensions of the holes, irrespective of the spin or interactions of the bosonic field. We also study the interaction between two long thin slits, for which the energy falls off as 1/r6.

  5. Nonlinear dynamics of axially moving plates

    NASA Astrophysics Data System (ADS)

    Ghayesh, Mergen H.; Amabili, Marco; Païdoussis, Michael P.

    2013-01-01

    The nonlinear dynamics for forced motions of an axially moving plate is numerically investigated using Von Kármán plate theory and retaining in-plane displacements and inertia. The equations of motion are obtained via an energy method based on Lagrange equations. This yields a set of second-order nonlinear ordinary differential equations with coupled terms. The equations are transformed into a set of first-order nonlinear ordinary differential equations and are solved via the pseudo-arclength continuation technique. The near-resonance nonlinear dynamics is examined via plotting the frequency-response curves of the system. Results are shown through frequency-response curves, time histories, and phase-plane diagrams. The effect of system parameters, such as the axial speed and the pretension, on the resonant responses is also highlighted.

  6. Experiments on elastic cloaking in thin plates.

    PubMed

    Stenger, Nicolas; Wilhelm, Manfred; Wegener, Martin

    2012-01-01

    Following a theoretical proposal [M. Farhat et al., Phys. Rev. Lett. 103, 024301 (2009)], we design, fabricate, and characterize a cloaking structure for elastic waves in 1 mm thin structured polymer plates. The cloak consists of 20 concentric rings of 16 different metamaterials, each being a tailored composite of polyvinyl chloride and polydimethylsiloxane. By using stroboscopic imaging with a camera from the direction normal to the plate, we record movies of the elastic waves for monochromatic plane-wave excitation. We observe good cloaking behavior for carrier frequencies in the range from 200 to 400 Hz (one octave), in good agreement with a complete continuum-mechanics numerical treatment. This system is thus ideally suited for demonstration experiments conveying the ideas of transformation optics. PMID:22304261

  7. Symbiotic Stars on Asiago Archive Plates

    NASA Astrophysics Data System (ADS)

    Jurdana-Šepić, Rajka; Munari, Ulisse

    2010-01-01

    The Asiago photographic archive has been searched for plates containing the symbiotic stars AS 210, AS 327, AX Per, BF Cyg, CI Cyg, DT Ser, EG And, GH Gem, Hen 2-442, Hen 3-1591, HM Sge, MaC 1-17, NSV 11776, Pe 2-16, Pt 1, PU Vul, RS Oph, T CrB, UV Aur, V1016 Cyg, V1329 Cyg, V352 Aql, V4018 Sgr, Wray 15-1470, and Z And. A total of 1617 good-quality plates imaging the program stars have been found and their brightness has been estimated using the Henden & Munari UBVRCIC local photometric sequences. The results for the objects with most abundant measurements are discussed.

  8. Observation of wave turbulence in vibrating plates.

    PubMed

    Boudaoud, Arezki; Cadot, Olivier; Odille, Benoît; Touzé, Cyril

    2008-06-13

    The nonlinear interaction of waves in a driven medium may lead to wave turbulence, a state such that energy is transferred from large to small length scales. Here, wave turbulence is observed in experiments on a vibrating plate. The frequency power spectra of the normal velocity of the plate may be rescaled on a single curve, with power-law behaviors that are incompatible with the weak turbulence theory of Düring et al. [Phys. Rev. Lett. 97, 025503 (2006)10.1103/PhysRevLett.97.025503]. Alternative scenarios are suggested to account for this discrepancy -- in particular the occurrence of wave breaking at high frequencies. Finally, the statistics of velocity increments do not display an intermittent behavior. PMID:18643508

  9. Ultrabroadband Elastic Cloaking in Thin Plates

    NASA Astrophysics Data System (ADS)

    Farhat, Mohamed; Guenneau, Sebastien; Enoch, Stefan

    2009-07-01

    Control of waves with metamaterials is of great topical interest, and is fueled by rapid progress in broadband acoustic and electromagnetic cloaks. We propose a design for a cloak to control bending waves propagating in isotropic heterogeneous thin plates. This is achieved through homogenization of a multilayered concentric coating filled with piecewise constant isotropic elastic material. Significantly, our cloak displays no phase shift for both backward and forward scattering. To foster experimental efforts, we provide a simplified design of the cloak which is shown to work in a more than two-octave frequency range (30 Hz to 150 Hz) when it consists of 10 layers using only 6 different materials overall. This metamaterial should be easy to manufacture, with potential applications ranging from car industry to antiearthquake passive systems for smart buildings, depending upon the plate dimensions and wavelengths.

  10. Analysis of hydraulic instability of ANS involute fuel plates

    SciTech Connect

    Sartory, W.K.

    1991-11-01

    Curved shell equations for the involute Advanced Neutron Source (ANS) fuel plates are coupled to two-dimensional hydraulic channel flow equations that include fluid friction. A complete set of fluid and plate boundary conditions is applied at the entrance and exit and along the sides of the plate and the channel. The coupled system is linearized and solved to assess the hydraulic instability of the plates.

  11. New technique for fixing rib fracture with bioabsorbable plate.

    PubMed

    Oyamatsu, Hironori; Ohata, Norihisa; Narita, Kunio

    2016-09-01

    Fixation of a bone fracture with a bioabsorbable plate made of poly-L-lactide and hydroxyapatite has received attention. We adopted this technique for a rib fracture by bending the plate into a U-shape and fixing it with suture through the holes in the mesh of the plate and holes that are drilled in the edge of the fractured rib. The suture is also wound around the plate. PMID:27206779

  12. Failure analysis of stainless steel femur fixation plate.

    PubMed

    Hussain, P B; Mohammad, M

    2004-05-01

    Failure analysis was performed to investigate the failure of the femur fixation plate which was previously fixed on the femur of a girl. Radiography, metallography, fractography and mechanical testing were conducted in this study. The results show that the failure was due to the formation of notches on the femur plate. These notches act as stress raisers from where the cracks start to propagate. Finally fracture occurred on the femur plate and subsequently, the plate failed. PMID:15468877

  13. Composite Bipolar Plate for Unitized Fuel Cell/Electrolyzer Systems

    NASA Technical Reports Server (NTRS)

    Mittelsteadt, Cortney K.; Braff, William

    2009-01-01

    In a substantial improvement over present alkaline systems, an advanced hybrid bipolar plate for a unitized fuel cell/electrolyzer has been developed. This design, which operates on pure feed streams (H2/O2 and water, respectively) consists of a porous metallic foil filled with a polymer that has very high water transport properties. Combined with a second metallic plate, the pore-filled metallic plates form a bipolar plate with an empty cavity in the center.

  14. A Measurement System for Spectrographic Plates

    NASA Astrophysics Data System (ADS)

    Nylén, Per

    1982-02-01

    An analysis system for measurement and data processing of spectra, recorded on spectrographic plates, is described. The system uses diode arrays for line profile scanning and a television camera for survey. The positions are measured using a Heidenhain equipment, and a micro-computer guides and controls the system. The computer is programmed to support the operator with utility routines for data collection and processing and for operator guidance.

  15. A mixed formulation for elastic multilayer plates

    NASA Astrophysics Data System (ADS)

    Fernandes, Amâncio

    2003-05-01

    A new approach based on a mixed formulation is proposed. The main advantage of such a formulation is that the transverse shear stress continuity is automatically satisfied in a natural way. In order to validate the model, comparisons of the proposed theory to Pagano's exact elasticity solutions are made for a bi-layer and a sandwich plate. To cite this article: A. Fernandes, C. R. Mecanique 331 (2003).

  16. Smov FOS Plate Scale (revisited - Replaces 5617)

    NASA Astrophysics Data System (ADS)

    Kinney, Anne

    1994-01-01

    The goal is to measure the precise plate scale and orientation. This will be acheived by performing a raster step and dwell sequence in the 4.3 arcsec aperture. The edges of the aperture should be avoided to prevent vignetting effects. An aperture map is required at each step of the dwell sequence. This test has to be conducted for both the RED and BLUE detectors. We will also determine the offset between the two detectors.

  17. Note: Heated flyer-plate impact system.

    PubMed

    Dolan, D H; Seagle, C T; Ao, T; Hacking, R G

    2014-07-01

    A technique for launching heated flyer plates was developed on a single-stage gas gun. This type of impact creates a well-posed mechanical state and a tunable thermal state, which is useful for calibrating dynamic temperature measurements. Proof-of-principle thermoreflectance measurements were performed using this technique. Since the target remains at room temperature until the moment of impact, heated flyers avoid differential expansion and annealing issues, allowing novel impact experiments to be performed. PMID:25085187

  18. SH wave propagation in piezoelectric coupled plates.

    PubMed

    Wang, Quan

    2002-05-01

    The propagation of shear horizontal (SH) wave in a piezoelectric coupled plate is investigated in this paper. Full account is taken of the piezoelectric coupling effect to the isotropic metal core in the mathematical model. One of the applications of this research is in the damage detection of the host metal structure from the wave propagation signal excited by the piezoelectric layer which is surface bonded on the surface of a metal core. This research is distinct from the previous works on SH propagation in piezoelectric structures because the piezoelectric materials were used as the core structure in the previous studies, and the potential of the studies was mainly on time-delay devices. The dispersive characteristics and the mode shapes of the transverse displacement and the electric potential of the piezoelectric layer are theoretically derived. The results from numerical simulations show that the phase velocity of the plate structure tends to the bulk shear wave velocity of the host metal core at high wavenumber when the shear wave velocity of host plate is larger than that of PZT bonded on it. Furthermore, there are three asymptotic solutions of wave propagation when the shear wave velocity of the host plate is smaller than that of PZT. The mode shape of the electric potential of the piezoelectric layer changes from the quadratic shape at lower wavenumber and with thinner piezoelectric layer to the shape with more zero nodes at higher wavenumber and with thicker piezoelectric layer. These findings are significant in the application of wave propagation in piezoelectric coupled structures. PMID:12046935

  19. Plate Tectonics: From Initiation of Subduction to Global Plate Motions (Augustus Love Medal Lecture)

    NASA Astrophysics Data System (ADS)

    Gurnis, Michael

    2013-04-01

    Plates are driven by buoyancy forces distributed in the mantle, within cooling oceanic plates (ridge push) and within subducted slabs. Although the case is often made that subducted slabs provide the principle driving force on plate motion, consensus has not been achieved. This is at least partially due to the great difficulty in realistically capturing the role of slabs in observationally-constrained models as slabs act to drive and resist plate motions through their high effective viscosity. Slab buoyancy acts directly on the edge of the plate (slab pull), while inducing mantle flow that tends to drag both subducting and overriding plates toward the trench. While plates bend during subduction they undergo a form of 'plastic failure' (as evident through faulting, seismicity and reduction of flexural parameters at the outer trench wall). The birth of a new subduction zone, subduction initiation, provides important insight into plate motions and subduction dynamics. About half of all subduction zones initiated over the Cenozoic and the geophysical and geological observations of them provide first order constraints on the mechanics of how these margins evolved from their preexisting tectonic state to self-sustaining subduction. We have examples of subduction initiation at different phases of the initiation process (e.g. early versus late) as well as how margins have responded to different tectonic forcings. The consequences of subduction initiation are variable: intense trench roll back and extensive boninitic volcanism followed initiation of the Izu-Bonin-Mariana arc while both were absent during Aleutian arc initiation. Such differences may be related to the character of the preexisting plates, the size of and forces on the plates, and how the lithosphere was initially bending during initiation. I will address issues associated with the forces driving plate tectonics and initiating new subduction zones from two perspectives. A common thread is the origin and

  20. Digital Copy of the Pulkovo Plate Collection

    NASA Astrophysics Data System (ADS)

    Kanaev, I.; Kanaeva, N.; Poliakow, E.; Pugatch, T.

    Report is devoted to a problem of saving of the Pulkovo plate collection. In total more than 50 thousand astronegatives are stored in the observatory. First of them are dated back to 1893. A risk of emulsion corrupting raises with current of time. Since 1996 the operation on digitization and record of the images of plates on electronic media (HDD, CD) are carried out in the observatory. The database ECSIP - Electronic Collection of the Star Images of the Pulkovo is created. There are recorded in it both complete, and extracted (separate areas) images of astronegatives. The plates as a whole are scanned on the photoscanner with rather rough optical resolution 600-2400 dpi. The matrixes with the separate images are digitized on the precision measuring machine "Fantasy" with high (6000-25400 dpi) resolution. The DB ECSIP allows to accept and to store different types of data of a matrix structure, including, CCD-frames. Structure of the ECSIP's software includes systems of visualization, processing and manipulation by the images, and also programs for position and photometric measurements. To the present time more than 40% completed and 10% extracted images from its total amount are digitized and recorded in DB ECSIP. The project is fulfilled at financial support by the Ministry of Science of Russian Federation, grant 01-54 "The coordinate -measuring astrographic machine "Fantasy".